2020

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In Australia, the spring  months are September, October and November.

• Plant new fruit trees and mulch the old ones well – put in some Rosellas – they look great! Lovely as cut flowers

• Spray flowers of Custard Apples, Carambola, Mangoes, Avocados & Apples with 1g of Boron per litre of water

• Sulphate of Potash & Magnesium/Boron in Sept. to citrus

• Now is the time to practice your grafting/marcotting skills

• If you want to topgraft your Mangoes to another variety, then prune now and wait for new growth to appear in summer, then topwork

• Start watering heavily once fruit appear on your trees.

Abiu	100gms Sulphate of Potash per sq mtr.
Avocado	Inject sick trees with half-strength Phosphorous acid end of Oct. early Nov. when spring growth matures.  You can spray but one injection equals 3 sprays. 2gms per sq mtr of Borax or half strength if using Solubor.  100gm sq.mtr Gypsum.
Bananas	Plant out now. Fertilise established clumps.
Citrus	Watch for Leaf Miner which affects new growth – spray only the new growth with Confidor & Seasol.  Spray Citrus with Pest Oil to control Aphids/Scale and Leaf Miner. Bronze Citrus Bug – use Baythroid or above or pick off by hand. One kilo of Dynamic Lifter and a closed hand of Nitrophoska Blue per sq mtr plus Gypsum and occasionally Dolomite. If you’re on sandy soil, one dressing of Zinc Sulphate 30gms per sq mtr will do the trick for 4 years for zinc. Also Sulphate of Potash & Magnesium/Boron. Spring is the time to bud graft.
Custard Apple	Leaf loss should occur.  Time to prune new shoots on trees so growth goes into fruit.  Mulch and low irrigation. Fertilise with chook manure and foliar fertilize with zinc. Lime Potash and Calcium = sweet fruit – 2 handfuls (it needs trace elements now) Start watering in October when flowering commences. With shy-bearing Pinks Mammoth, spray the flowers with a mixture of 1tsp Borax, 1tsp Urea with 1ltr water. Use zinc on Cuban Fibreless Soursop to make it fruit
Feijoas	Jan – Apply half a handful of Super before flowering.
Figs	In July prune 2/3rds off as fruit is only produced on new wood of new seasons growth. Fertilize and mulch well.  Spray Mancozeb for Brown Spot & Rust control with Carbaryl to control the Fig Beetle and then monthly until harvest.
Green Sapote	Difficult to set fruit so Kaspar recommends a mix of fertilizers to the dripline: 2 cups Magnesium (Epsom Salts) half cup Zinc Sulphate Heptahydrate, half cup Agricultural Boron (Borax OK)
Jaboticaba	September – Fertilize with a handful of Potash 50g/m2
Lychee	A boron spray or two on the developing flowers is a good idea to ensure flower fertility. Increase irrigation during early fruit development.  Ease off the irrigation from early November (moderate water stress in December / early January can reduce fruit drop).
Mango	Once flowering occurs, spray with Mancozeb based spray every 2 weeks if anthracnose is present on flowers then copper on monthly on your fruit. Foliar fertilize with a 1% solution of Potassium Nitrate at beginning of flowering and repeat every 7-10 days later – induces flowering and fruit set. If you get a lot of rain that wrecks the flowers, prune off the diseased inflorescences (only) and they will usually flower again.Apply Calcium and Boron foliar fertilizer to flowers only when panicles are finger length every 14-21 days through the flowering phase until fruit reaches golfball size. If you want to topwork ie. graft another variety on, then now is the time to cut back the branches as you’ll be grafting onto the new shoots Jan – Mar next year. Florigon variety suggested for the Brisbane area. Start watering heavily once fruit has set on your trees.
Passionfruit	Vines come out of dormancy – apply fertilizer and mulch out to 2-3 metres.
Pawpaw	Spray with Wettable Sulphur with a wetting agent in the evening if Spider Mite is present. Half a teaspoon of Borax per plant/ m2.
Rollinia	Foliar fertilise with a 1% solution of zinc sulphate
Stone Fruit	Water well/prune out water shoots and dense foliage for better fruit size. Start fruit fly control program when fruit half grown. Take cuttings 45cm long from 1 or 2 year old wood. Remove leaves & cut squarely at the base immediately below a node. Only select cuttings from disease free plants.
Tamarillos	Flowering commences in the early varieties – low irrigation requirement
White & Black Sapote	Tip prune in October

Authored by: 

Sheryl Backhouse from various sources

Sourced from: 

STFC Newsletter October – November 2006

Date sourced: 

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This is a widely distributed shrub from Madagascar and Africa and it’s found widely through the tropics. The leaves are shiny and from 7-20cm long and are pale green in colour and are opposite on the branches. At fruiting time, small greenish white flowers are borne in clusters in the axils of the leaves and from these round to pear shaped fruit develop which can be up to 5cm and contain 4 or 5 large seeds. The fruit at full maturity is green smooth and has white dots, but if allowed to remain on the bush after maturity eventually the fruits shrivel and become brown in colour. At this stage the flavour is suggestive of the tamarind. You can also eat the fruit when it is fresh at full maturity and it is sweet and sub-acid suggesting an unripe or greenish apple. The shrubs are reported to be quite drought tolerant and seemingly well adapted for a wide variety of soil. Propagation is easily accomplished by cuttings or planting seeds and there has been little if any selection of superior varieties. Cold hardiness is unknown, but it should definitely be tried.

Authored by: 

Gene Joyner Palm Beach County Co-op Ext. Service

Sourced from: 

Sub-Tropical Fruit Club of Qld. Inc Newsletter June – July 2007

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Of the 60 or more species of the genus Annona, family Annonaceae, the soursop, A. muricata L., is the most tropical, the largest-fruited, and the only one lending itself well to preserving and processing. It is generally known in most Spanish-speaking countries as guanabana; in E1 Salvador, as guanaba; in Guatemala, as huanaba; in Mexico, often as zopote de viejas, or cabeza de negro; in Venezuela, as catoche or catuche; in Argentina, as anona de puntitas or anona de broquel; in Bolivia, sinini; in Brazil, araticum do grande, graviola, or jaca do Para; in the Netherlands Antilles, sorsaka or zunrzak, the latter name also used in Surinam andJava; in French-speaking areas of the West Indies, West Africa, and Southeast Asia, especially North Vietnam, it is known as corossol, grand corossol, corossol epineux, or cachiman epineux. In Malaya it may be called durian belanda, durian maki; or seri kaya belanda; in Thailand, thu-rian-khack. In 1951, Prof. Clery Salazar, who was encouraging the development of soursop products at the College of Agriculture at Mayaguez, Puerto Rico, told me that they would like to adopt an English name more appealing than the word “soursop”, and not as likely as guanabana to be mispronounced. To date, no altematives have been chosen.

Fig. 21: The soursop tree may bear fruits anywhere on its trunk or branches. Multiple-stems of this tree are the result of its having been frozen to the ground more than once.

Description The soursop tree is low-branching and bushy but slender because of its upturned limbs, and reaches a height of 25 or 30 ft (7.5-9 m). Young branchlets are rusty-hairy. The malodorous leaves, normally evergreen, are alternate, smooth, glossy, dark green on the upper surface, lighter beneath; oblong, elliptic or narrowobovate, pointed at both ends, 2 1/2 to 8 in (6.25-20 cm) long and 1 to 2 1/2 in (2.5-6.25 cm) wide. The flowers, which are borne singly, may emerge anywhere on the trunk, branches or twigs. They are short stalked, 1 1/2 to 2 in (4 5 cm) long, plump, and triangular-conical, the 3 fleshy, slightly spreading, outer petals yellow-green, the 3 close-set inner petals pale-yellow.

The fruit is more or less oval or heart-shaped, some times irregular, lopsided or curved, due to improper carper development or insect injury. The size ranges from 4 to 12 in (10-30 cm) long and up to 6 in (15 cm) in width, and the weight may be up to 10 or 15 lbs (4.5-6.8 kg). The fruit is compound and covered with a reticulated, leathery-appearing but tender, inedible, bitter skin from which protrude few or many stubby, or more elongated and curved, soft, pliable “spines”. The tips break off easily when the fruit is fully ripe. The skin is dark-green in the immature fruit, becoming slightly yellowish-green before the mature fruit is soft to the touch. Its inner surface is cream-colored and granular and separates easily from the mass of snow-white, fibrous, juicy segments—much like flakes of raw fish—surrounding the central, soft-pithy core. In aroma, the pulp is somewhat pineapple-like, but its musky, subacid to acid flavor is unique. Most of the closely-packed segments are seedless. In each fertile segment there is a single oval, smooth, hard, black seed, l/2 to 3/4 in (1.25-2 cm) long; and a large fruit may contain from a few dozen to 200 or more seeds.

Origin and Distribution
Oviedo, in 1526, described the soursop as abundant in the West Indies and in northern South America. It is today found in Bermuda and the Bahamas, and both wild and cultivated, from sea-level to an altitude of 3,500 ft (1,150 m) throughout the West Indies and from southern Mexico to Peru and Argentina. It was one of the first fruit trees carried from America to the Old World Tropics where it has become widely distributed from southeastern China to Australia and the warm lowlands of eastern and western Africa. It is common in the markets of Malaya and southeast Asia. Very large, symmetrical fruits have been seen on sale in South Vietnam. It became well established at an early date in the Pacific Islands. The tree has been raised successfully but has never fruited in Israel. In Florida, the soursop has been grown to a limited extent for possibly 110 years. Sturtevant noted that it was not included by Atwood among Florida fruits in 1867 but was listed by the American Pomological Society in 1879. A tree fruited at the home of John Fogarty of Manatee before the freeze of 1886. In the southeastern part of the state and especially on the Florida Keys, it is often planted in home gardens. In regions where sweet fruits are preferred, as in South India and Guam, the soursop has not enjoyed great popularity. It is grown only to a limited extent in Madras. However, in the East Indies it has been acclaimed one of the best local fruits. In Honolulu, the fruit is occasionally sold but the demand exceeds the supply. The soursop is one of the most abundant fruits in the Dominican Republic and one of the most popular in Cuba, Puerto Rico, the Bahamas, Colombia and northeastern Brazil. In 1887, Cuban soursops were selling in Key West, Florida, at 10 to 50 cents apiece. In 1920, Wilson Popenoe wrote that: “In the large cities of tropical America, there is a good demand for the fruits at all times of the year, a demand which is not adequately met at present.” The island of Grenada produces particularly large and perfect soursops and regularly delivers them by boat to the market of Port-of Spain because of the shortage in Trinidad. In Colombia, where the soursop is generally large, well-formed and of high quality, this is one of the 14 tropical fruits recommended by the Instituto Latinoamericano de Mercadeo Agricola for large-scale planting and marketing. Soursops produced in small plots, none over 5 acres (2.27 ha), throughout Venezuela supply the processing plants where the frozen concentrate is packed in 6 oz (170 g) cans. In 1968, 2,266 tons (936 MT) of juice were processed in Venezuela. The strained pulp is also preserved commercially in Costa Rica. There are a few commercial soursop plantations near the south coast of Puerto Rico and several processing factories. In 1977, the Puerto Rican crop totaled 219,538 lbs (99,790 kg). At the First International Congress of Agricultural and Food Industries of the Tropical and Subtropical Zones, held in 1964, scientists from the Research Laboratories of Nestle Products in Vevey, Switzerland, presented an evaluation of lesser-known tropical fruits and cited the soursop, the guava and passionfruit as the 3 most promising for the European market, because of their distinctive aromatic qualities and their suitability for processing in the form of preserved pulp, nectar and jelly.

Varieties
In Puerto Rico, the wide range of forms and types of seedling soursops are roughly divided into 3 general classifications: sweet, subacid, and acid; then subdivided as round, heart-shaped, oblong or angular; and finally classed according to flesh consistency which varies from soft and juicy to firm and comparatively dry. The University of Puerto Rico’s Agricultural Experiment Station at one time cataloged 14 different types of soursops in an area between Aibonito and Coamo. In El Salvador, 2 types of soursops are distinguished: guanaba azucaron (sweet) eaten raw and used for drinks; and guanaba acida (very sour), used only for drinks. In the Dominican Republic, the guanabana dulce (sweet soursop) is most sought after. The term “sweet” is used in a relative sense to indicate low acidity. A medium-sized, yellow-green soursop called guanabana sin fibre (fiberless) has been vegetatively propagated at the Agricultural Experiment Station at Santiago de las Vegas, Cuba. The foliage of this superior clone is distinctly bluish-green. In 1920, Dr. Wilson Popenoe sent to the United States Department of Agriculture, from Costa Rica, budwood of a soursop he named ‘Bennett’ in honour of G.S. Bennett, Agricultural Superintendent of the Costa Rican Division of the United Fruit Company. He described the fruit as large and handsome (as shown in the photograph accompanying the introduction record No. 51050) and he declared the tree to be the most productive he had seen.

Climate
The soursop is truly tropical. (Sheryl: It grows & fruits very well in SE Qld) Young trees in exposed places in southem Florida are killed by only a few degrees of frost. The trees that survive to fruiting age on the mainland are in protected situations, close to the south side of a house and sometimes near a source of heat. Even so, there will be temporary defoliation and interruption of fruiting when the temperature drops to near freezing. In Key West, where the tropical breadfruit thrives, the soursop is perfectly at home. In Puerto Rico, the tree is said to prefer an altitude between 800 and 1,000 ft (244300 m), with moderate humidity, plenty of sun and shelter from strong winds.

Soil
Best growth is achieved in deep, rich, well-drained, semi-drysoil, but the soursop tree can be and is commonly grown in acid and sandy soil, and in the porous, oolitic limestone of South Florida and the Bahama Islands.

Propagation
The soursop is usually grown from seeds. They should be sown in flats or containers and kept moist and shaded. Germination takes from 15 to 30 days. Selected types can be reproduced by cuttings or by shield-budding. Soursop seedlings are generally the best stock for propagation, though grafting onto custard apple (Annona reticulata), the mountain soursop (A. montana), or pond apple (A. glabra), is usually successful. The pond apple has a dwarfing effect. Grafts on sugar apple (A. squamosa) and cherimoya (A. cherimola) do not live for long, despite the fact that the soursop is a satisfactory rootstock for sugar apple in Ceylon and India.

Culture
In ordinary practice, seedlings, when 1 ft (30 cm) or more in height are set out in the field at the beginning of the rainy season and spaced 12 to 15 ft (3.65-4.5 m) apart, though 25 ft (7.5 m) each way has been suggested. A spacing of 20 x 25 ft (6×7.5 m) allows 87 trees per acre (215/ha). Close-spacing, 8 x 8 ft (2.4×2.4 m) is thought sufficient for small gardens in Puerto Rico. The tree grows rapidly and begins to bear in 3 to 5 years. In Queensland, well-watered trees have attained 15 to 18 ft (4.5-5.5 m) in 6 to 7 years. Mulching is recommended to avoid dehydration of the shallow, fibrous root system during dry, hot weather. If in too dry a situation, the tree will cast off all of its old leaves before new ones appear. A fertilizer mixture containing 10% phosphoric acid, 10% potash and 3% nitrogen has been advocated in Cuba and Queensland. But excellent results have been obtained in Hawaii with quarterly applications of 10-10-10 N P K—1\2 lb (.225 kg) per tree the first year, 1 lb (.45 kg)/tree the 2nd year, 3 lbs (1.36 kg)/tree the 3rd year and thereafter.

Season
The soursop tends to flower and fruit more or less continuously, but in every growing area there is a principal season of ripening. In Puerto Rico, this is from March to June or September; in Queensland, it begins in April; in southern India, Mexico and Florida, it extends from June to September; in the Bahamas, it continues through October. In Hawaii, the early crop occurs from January to April; midseason crop, June to August, with peak in July; and there is a late crop in October or November.

Harvesting
The fruit is picked when full grown and still firm but slightly yellow-green. If allowed to soften on the tree, it will fall and crush. It is easily bruised and punctured and must be handled with care. Firm fruits are held a few days at room temperature. When eating ripe, they are soft enough to yield to the slight pressure of one’s thumb. Having reached this stage, the fruit can be held 2 or 3 days longer in a refrigerator. The skin will blacken and become unsightly while the flesh is still unspoiled and usable. Studies of the ripening process in Hawaii have determined that the optimum stage for eating is 5 to 6 days after harvest, at the peak of ethylene production. Thereafter, the flavour is less pronounced and a faint offodor develops. In Venezuela, the chief handicap in commercial processing is that the fruits stored on racks in a cool shed must be gone over every day to select those that are ripe and ready for juice extraction.

Yield
The soursop, unfortunately, is a shy-bearer, the usual crop being 12 to 20 or 24 fruits per tree. In Puerto Rico, production of 5,000 to 8,000 lbs per acre (roughly equal kg/ha), is considered a good yield from well-cared-for trees. A study of the first crop of 35 5 year-old trees in Hawaii showed an average of 93.6 lbs (42.5 kg) of fruits per tree. Yield was slightly lower the 2nd year. The 3rd year, the average yield was 172 lbs (78 kg) per tree. At this rate, the annual crop would be 16,000 lbs per acre (roughly equal kg/ha).

Pests & Diseases Queensland’s principal soursop pest is the mealybug which may occur in masses on the fruits. The mealybug is a common pest also in Florida, where the tree is often infessed with scale insects. Sometimes it may be infected by a lace-wing bug.

The fruit is subject to attack by fruit flies—Anastrepha suspensa, A. striata and Ceratitis capitata. Red spiders are a problem in dry climates.

Dominguez Gil (1978 and 1983), presents an extensive list of pests of the soursop in the State of Zulia, Venezuela. The 5 most damaging are: 1) the wasp, Bephratelloides (Bephrata) maculicollis, the larvae of which live in the seeds and emerge from the fully-grown ripe fruit, leaving it perforated and highly perishable; 2) the moth, Cerconota (Stenoma) anonella, which lays its eggs in the very young fruit causing stunting and malformation; 3) Corythucha gossipii; which attacks the leaves; 4) Cratosomus inaequalis, which bores into the fruit, branches and trunk; 5) Laspeyresia sp., which perforates the flowers. The first 3 are among the 7 major pests of the soursop in Colombia, the other 4 being: Toxoptera aurantii; which affects shoots, young leaves, flowers and fruits; present but not important in Venezuela; Aphis spiraecola; Empoasca sp., attacking the leaves; and Aconophora concolor, damaging the flowers and fruits. Important beneficial agents preying on aphids are A phidius testataceipes, Chrysopa sp., and Curinus sp. Lesser enemies of the soursop in South America include: Talponia backeri and T. batesi which damage flowers and fruits; Horiola picta and H. lineolata, feeding on flowers and young branches; Membracis foliata, attacking young branches, flower stalks and fruits; Saissetia nigra; Escama ovalada, on branches, flowers and fruits; Cratosomus bombina, a fruit borer; and Cyclocephala signata, affecting the flowers. In Trinidad, the damage done to soursop flowers by Thecla ortygnus seriously limits the cultivation of this fruit. The sphinx caterpillar, Cocytius antueus antueus may be found feeding on soursop leaves in Puerto Rico. Bagging of soursops is necessary to protect them from Cerconota anonella. However, one grower in the Magdalena Valley of Colombia claims that bagged fruits are more acid than others and the flowers have to be handpollinated.

It has been observed in Venezuela and El Salvador that soursop trees in very humid areas often grow well but bear only a few fruits, usually of poor quality, which are apt to rot at the tip. Most of their flowers and young fruits fall because of anthracnose caused by Collectotrichum gloeosporioides. It has been said that soursop trees for cultivation near San Juan, Puerto Rico, should be seedlings of trees from similarly humid areas which have greater resistance to anthracnose than seedlings from dry zones. The same fungus causes damping-off of seedlings and die-back of twigs and branches. Occasionally the fungus, Scolecotrichum sp. ruins the leaves in Venezuela. In the East Indies, soursop trees are sometimes subject to the root-fungi, Fomes lamaoensis and Diplodia sp. and by pink disease due to Corticum salmonicolor.

Food Uses Soursops of least acid flavor and least fibrous consistency are cut in sections and the flesh eaten with a spoon. The seeded pulp may be torn or cut into bits and added to fruit cups or salads, or chilled and served as dessert with sugar and a little milk or cream. For years, seeded soursop has been canned in Mexico and served in Mexican restaurants in New York and other northern cities. Most widespread throughout the tropics is the making of refreshing soursop drinks (called champola in Brazil; carato in Puerto Rico). For this purpose, the seeded pulp may be pressed in a colander or sieve or squeezed in cheesecloth to extract the rich, creamy juice, which is then beaten with milk or water and sweetened. Or the seeded pulp may be blended with an equal amount of boiling water and then strained and sweetened. If an electric blender is to be used, one must first be careful to remove all the seeds, since they are somewhat toxic and none should be accidentally ground up in the juice. In Puerto Rican processing factories, the hand-peeled and cored fruits are passed through a mechanical pulper having nylon brushes that press the pulp through a screen, separating it from the seeds and fiber. A soursop soft drink, containing 12 to 15% pulp, is canned in Puerto Rico and keeps well for a year or more. The juice is prepared as a carbonated bottled beverage in Guatemala, and a fermented, cider-like drink is sometimes made in the West Indies. The vacuum-concentrated juice is canned commercially in the Philippines. There soursop drinks are popular but the normal “milk” colour is not. The people usually add pink or green food coloring to make the drinks more attractive. The strained pulp is said to be a delicacy mixed with wine or brandy and seasoned with nutmeg. Soursop juice, thickened with a little gelatine, makes an agreeable dessert. In the Dominican Republic, a soursop custard is enjoyed and a confection is made by cooking soursop pulp in sugar syrup with cinnamon and lemon peel. Soursop ice cream is commonly frozen in refrigerator ice-cube trays in warm countries. In the Bahamas, it is simply made by mashing the pulp in water, letting it stand, then straining to remove fibrous material and seeds. The liquid is then blended with sweetened condensed milk, poured into the trays and stirred several times while freezing. A richer product is made by the usual method of preparing an ice cream mix and adding strained soursop pulp just before freezing. Some Key West restaurants have always served soursop ice cream and now the influx of residents from the Caribbean and Latin American countries has created a strong demand for it. The canned pulp is imported from Central America and Puerto Rico and used in making ice cream and sherbet commercially. The pulp is used, too, for making tarts and jelly, syrup and nectar. The syrup has been bottled in Puerto Rico for local use and export. The nectar is canned in Colombia and frozen in Puerto Rico and is prepared fresh and sold in paper cartons in the Netherlands Antilles. The strained, frozen pulp is sold in plastic bags in Philippine supermarkets.

Immature soursops are cooked as vegetables or used in soup in Indonesia. They are roasted or fried in northeastern Brazil. I have boiled the half-grown fruit whole, without peeling. In an hour, the fruit is tender, its flesh off-white and mealy, with the aroma and flavour of roasted ears of green corn (maize).

Food Value of Soursop per 100g of Edible Portion

Calories	61.3-53.1
Moisture	82.8g
Protein	1.00g
Fat	0.97g
Carbohydrates	14.63g
Fiber	0.79g
Ash	60g
Calcium	10.3 mg
Phosphorus	27.7 mg
Iron	0.64 mg
Vitamin A (B-carotene)	0
Thiamine	0.11 mg
Riboflavin	0.05 mg
Niacin	1.28mg
Ascorbic Acid	29.6 mg
Amino Acids:
Tryptophan	11 mg
Methionine	7 mg
Lysine	60mg

*Analyses made at the Laboratorio FIM de Nutricion, Havana, Cuba.

Toxicity The presence of the alkaloids anonaine and anoniine has been reported in this species. The alkaloids muricine, C19H21O4N (possibly des-N-methylisocorydine or des-N methylcorydine) and muricinine, C18H19O4 (possibly des-N-methylcorytuberine), are found in the bark. Muricinine is believed to be identical to reticuline. An unnamed alkaloid occurs in the leaves and seeds. The bark is high in hydrocyanic acid. Only small amounts are found in the leaves and roots and a trace in the fruit. The seeds contain 45% of a yellow non-drying oil which is an irritant poison, causing severe eye inflarnmation. Other Uses Fruit: In the Virgin Islands, the fruit is placed as a bait in fish traps. Seeds: When pulverized, the seeds are effective pesticides against head lice, southern army worms and pea aphids and petroleum ether and chloroform extracts are toxic to black carpet beetle larvae. The seed oil kills head lice. Leaves: The leaf decoction is lethal to head lice and bedbugs. Bark: The bark of the tree has been used in tanning. The bark fiber is strong but, since fruiting trees are not expendable, is resorted to only in necessity. Bark, as well as seeds and roots, has been used as fish poison.

Wood: The wood is pale, aromatic, soft, light in weight and not durable. It has been used for ox yokes because it does not cause hair loss on the neck. In Colombia, it is deemed to be suitable for pipestems and barrelstaves. Analyses in Brazil show cellulose content of 65 to 76%, high enough to be a potential source of paper pulp.

Medicinal Uses: The juice of the ripe fruit is said to be diuretic and a remedy for haematuria and urethritis. Taken when fasting, it is believed to relieve liver ailments and leprosy. Pulverized immature fruits, which are very astringent, are decocted as a dysentery remedy. To draw out chiggers and speed healing, the flesh of an acid soursop is applied as a poultice unchanged for 3 days. In Materia Medica of British Guiana, we are told to break soursop leaves in water, “squeeze a couple of limes therein, get a drunken man and rub his head well with the leaves and water and give him a little of the water to drink and he gets as sober as a judge in no time.” This sobering or tranquilizing formula may not have been widely tested, but soursop leaves are regarded throughout the West Indies as having sedative or soporific properties. In the Netherlands Antilles, the leaves are put into one’s pillowslip or strewn on the bed to promote a good night’s sleep. An infusion of the leaves is commonly taken internally for the same purpose. It is taken as an analgesic and antispasmodic in Esmeraldas Province, Ecuador. In Africa, it is given to children with fever and they are also bathed lightly with it. A decoction of the young shoots or leaves is regarded in the West Indies as a remedy for gall bladder trouble, as well as coughs, catarrh, diarrhoea, dysentery and indigestion; is said to “cool the blood,” and to be able to stop vomiting and aid delivery in childbirth. The decoction is also employed in wet compresses on inflammations and swollen feet. The chewed leaves, mixed with saliva, are applied to incisions after surgery, causing proud flesh to disappear without leaving a scar. Mashed leaves are used as a poultice to alleviate eczema and other skin afflictions and rheumatism, and the sap of young leaves is put on skin eruptions. The roots of the tree are employed as a vermifuge and the root bark as an antidote for poisoning. A tincture of the powdered seeds and bay rum is a strong emetic. Soursop flowers are believed to alleviate catarrh.       
In Puerto Rico, the wide range of forms and types of seedling soursops are roughly divided into 3 general classifications: sweet, subacid, and acid; then subdivided as round, heart-shaped, oblong or angular; and finally classed according to flesh consistency which varies from soft and juicy to firm and comparatively dry. The University of Puerto Rico’s Agricultural Experiment Station at one time catalogued 14 different types of soursops in an area between Aibonito and Coamo. In El Salvador, 2 types of soursops are distinguished: guanaba azucaron (sweet) eaten raw and used for drinks; and guanaba acida (very sour), used only for drinks. In the Dominican Republic, the guanabana dulce (sweet soursop) is most sought after. The term “sweet” is used in a relative sense to indicate low acidity. A medium-sized, yellow-green soursop called guanabana sin fibre (fiberless) has been vegetatively propagated at the Agricultural Experiment Station at Santiago de las Vegas, Cuba. The foliage of this superior clone is distinctly bluish-green. In 1920, Dr. Wilson Popenoe sent to the United States Department of Agriculture, from Costa Rica, budwood of a soursop he named ‘Bennett’ in honour of G.S. Bennett, Agricultural Superintendent of the Costa Rican Division of the United Fruit Company. He described the fruit as large and handsome (as shown in the photograph accompanying the introduction record No. 51050) and he declared the tree to be the most productive he had seen.

Ref:  http://www.hort.purdue.edu/newcrop/morton/soursop.html

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Dirt soils – are they the same?  No!  Are they close?  No.

Soil has been one of my interests and loves since my college days. My background has been as a Park Ranger Naturalist and I did my Upper Division course work in soils and the ecology of soils. We talked about soils based on those mineral components and we divided our soils up between sand, silt and clay. The common misconception people have is that one’s good; one’s bad. There is no such thing. In nature, there is no such thing. In nature, there is no good and bad. It’s all trade-offs. Sands have benefits; sands have disadvantages. Clays have benefits; clays have disadvantages. Silts are a mixture – give me the best of a small world? 

Sand  Benefits of sand are they have great drainage; greater aeration; they don’t compact. Go out on the beach and jump up and down and come along with a pale and sand bucket and dig holes; the lifeguard can drive up and down the beach – sand doesn’t compact. Clays have advantages. They hold moisture; they hold nutrients; they have a high cat ion exchange capability. You apply nutrients in the form of fertiliser or other organic sources. They bind those and keep them available for plant uptake. They don’t leach through the soil. The disadvantages of sand is that they have good aeration and drainage – they dry out quickly; they need to be watered frequently; they don’t hold nutrients well so when you apply fertilisers they flush through the soil profile and they don’t bind the soil particles that remain available so you sands require fertilisers more frequently or you use a slow release form of fertiliser that remains in the root zone for a longer duration.

Clays have problems. They don’t drain well, they hold moisture too long and they compact easily. Probably the worst thing I have heard people do with sand and clay soils is they say “well, my clay holds moisture and my sand doesn’t and my sand has good aeration and my clay doesn’t, and my sand needs to hold more nutrients and my clay has good cat ion exchange ……., I’ll mix my clay and sand together or if I have clay soil, I’ll mix sand into it and it will improve the drainage, get better aeration, prevent compaction and …..wrong!”  If any of you have any construction background, how do you mix concrete?  Sand and cement. Cement is a clay so you take clay and sand and you add a little gravel and mix it but you didn’t get soil. Soils are a lot more than the mineral component. Soils ecology is the complex system of living, dead and dying organisms as well as mineral components and oxygen, water, bacteria, fungus, insects, roots and all of the interactions going on in that soil profile. It’s an eco system and similar to the eco system of the ocean, there are strata or layers of the eco system. Organisms that live in the surface few inches of soil cannot survive a foot beneath the surface. Organisms that live a foot beneath the surface of the soil cannot live on the surface and tilling your soil is not a good practice. Common for many decades we would plough the ground and you see advertisers who have cultivators and they tell you to go around your trees to control weeds and when you do that you’re disrupting the soil organism ecosystems causing problems for that soil. Now lets combine that fact with the way plants and trees grow.

On each tree, your root systems have 3 functions:

(1) is to anchor the plant and keep it upright.

(2) is to store food and nutrients to keep it through its dormant period.

(3) is to pick up water and nutrients.

The roots that pick up water and nutrients are cut out at the ends of the growing and developing roots are very fine delicate new growth called root hairs. These root hairs are extremely fragile and those are the roots that pick up water and nutrients – 70% of the root hairs – they are also known as feeder roots occur within the surface one foot of soil. 90% of the root hairs occur with the surface 3 feet of soil. We talk about deep root plants, tap roots, deep water and irrigating.

70% of feeder roots within the surface 1 ft of soil is where you want to focus your water and fertiliser programs. Deep watering your plants doesn’t mean putting probes and pipes into the soil and watering 3ft beneath the surface of the soil – there are no feeder roots there. Roots grow in the presence of water and air. Too much of either one or too little of either one and roots die. So in natural ground soils, in California we don’t have any ground water to speak of, the only ground water that’s available is what comes from the surface down. Also, oxygen exchange occurs from the surface down and when you have clay soils, the oxygen exchange occurs from the surface into the soil profile and it’s the lack of oxygen which often accounts for the lack of root development in the soil profile.

Growing in the ground, it has long been tradition to amend or prepare the soils before planting your trees, shrubs etc. They would tell you “dig a hole twice as wide, twice as deep, amend the soil with 30%-50% of organic material and use that to fill to acclimatise the container grown plant to the native soil. This is wrong. This is not a good recommendation especially when we’re dealing with clay soils, compacted soils, poor quality soils. Why? Because what happens is that we amend the planting zone and you have a plant that is growing in the landscape, how far out should the root system develop on a mature established plant? Two to three times the height of the plant in radius. That means that the 10 ft tree in your front yard has a root system that is 30 – 60 ft in diameter and you’re amending a hole 3ft across!!! Where’s the benefit? To help it get established? That was the claim! The claim seemed to hold true because we take a tree and plant it in the amended hole and plant another in the native ground, the one in the amended hole seems to grow faster, quicker, bigger – more rapidly but what happens in the long term is the roots contact the native soil and especially where your soils are poor, the roots want to stay in that amended hole where life is good and the root system does not develop well into the native ground. Plants which were done as a test to determine which was the best soil amendment to use, studies were done initially out of Oklahoma, Davis California plus several other universities throughout the country to determine what was the best soil amendment to add to the planting holes when planting trees and shrubs and repeatedly the outcome was the group which were the control where no soil amendments were added, outgrew and outperformed the other trees in the long term. These trees developed root systems into the native soil without any interface or transition problem and became better established, healthier, stronger trees than those where soil amendments were used. Soil amendments in the planting holes also have some other problems. Amendments have traditionally been organic material. What happens to organic material over time? It decomposes and as it decomposes, we lose aeration and drainage and you add organic material into a planting hole and that organic material decomposes as the plant settles and now the roots at the bottom of the planting hole lack oxygen and they develop rootrot. If the plant settles below ground? and the soil fills in to cover higher on the trunk on the plant, the plant can develop crown rot. Furthermore, it is the physical property of water that as you change from one texture soil to another texture of soil, water will not move from the first into the second until the first is saturated so you can end up with what is called “perched water tables” and instead of improving drainage, you often cause poor drainage soils to be much worse. Organisations like International Society of Arboriculture no longer recommend soil amendments for planting trees and shrubs. The Nurserymans’ Association for decades argued that soil amendments are a big part of our sales and if we tell people not to use soil amendments, then we’ll lose sales but now even that association do not recommend soil amendments in the planting hole.  Plant them in the native dirt but before you do, make sure that dirt drains adequately so that water and air move through the soil profile and as the water passes through the root zone of the plant, it pulls air in behind it – it fills the pore space in the soil. Drainage is imperative and adding soil amendments in planting holes does not improve drainage. Poor drainage soils are like bathtubs. If you dig a hole and fill it full of water and it doesn’t drain, it’s like a bathtub with a stopped up drain. If you have a bathtub with a stopped off drain and add soil amendments or organic material in your bathtub, what do you have? A swamp, mud, a peatbog. It didn’t fix the drainage. You just appear to because what people do is dig these big holes and water drains below the surface, you don’t see it so it and it sits on the bottom and the roots rot and that’s fine as long as the only water you get is from your irrigation because you can irrigate in moderation so that the water doesn’t fill up the hole from the top. Then you get a wet season and that hole fills up with water and the roots drown and die. We see that every wet winter in California. We pull out trees that have been growing for years because the root can’t get adequate amounts of air.

Mulching as opposed to amending the soil is the single best thing you can do for your soil. Think of the soils that we are all envious of. Those beautiful black soils of Illinois, Iowa. How did those soils develop naturally? Nobody added soil amendments into them. They developed by organic material falling from plants and trees that covered the soil and decomposed it from the surface downward. It was the action of the organisms within the soil; the earthworms, the bugs, the fungi, the bacteria that caused those organic materials to decompose and as they decomposed they produced humic acids that helped to dissolve excess salt, improve drainage, break up clay particles, improve aeration and to improve your soil, mulching is by far the single best thing you can do to your soil. Add to that the fact that it is feasible to amend the entire root zone of the plant. Can you amend an area 60 feet in diameter by 3 feet deep? You can with a backhoe and plenty of money but it’s not really practicable but you can mulch that same area 3 inches deep and mulching on a regular program keeping the mulch 2-3 inches over the surface of the soil, replenishing it as it decomposes will improve your soil in a number of years so that now instead of having poor soils, you have a rich growing area for the roots of your plants.

There are some things you can do to your soils that are beneficial in the way of chemical treatment.  Southern Californian soils are typically desert soils and desert soils are typically high in pH – they have a fair amount of salt because of the water quality that we get from the Colorado River. pH of soils in southern California average about 7.3-7.8 which is somewhat alkaline. Most plants prefer a pH of soil to grow in which is somewhere in the neighbourhood of 6.5 and they like it slightly acid. Tropical and sub-tropical plants like even a little more acid than that 6 to 6.5 are usually ideal for most of your sub-tropicals so how can we modify our soils to lower the pH and alleviate some of these salts? With mulching techniques and the addition of chemical treatment. Chemical is not necessarily a bad word. Chemicals can simply be inorganic materials – Gypsum is a naturally occurring mineral.  Soil sulphur in the form of sulphate anions is often used to alter the pH of your soil. It doesn’t do it overnight. Gypsum with 12-18% sulphate can change the pH of your soil but it doesn’t do it overnight. It relies on a bacteria in your soil to convert the sulphate to a water soluble form that changes the pH of your soil. The addition of things like gypsum is beneficial but you need the association of the bacteria and it takes time so it will be 3-6 months before you see any change. Gypsum has some other benefits – it can help to replace sodium in your soil with calcium. Sodium is detrimental to plants and it will allow the sodium ions to leach more freely through the soil profile. Calcium is a secondary nutrient that’s valuable for plant health so adding things like gypsum can be beneficial. Also gypsum in some clays and it’s not a magic pill, can cause clay particles to bind together into clumps called aggregates and as it binds together, it opens up larger pore space between the aggregate, allowing water to pass through. Adding things like gypsum to our soils can be beneficial on a yearly program. Gypsum is largely water insoluble so taking gypsum and spreading it out on the surface of your soil has limited benefit. There are more water soluble products that are better at improving the soil structure chemically when applied to the surface and watered in. One product is called Soil Buster, another is called Liquid Gypsum and those have some real improvements. Mulch your soil with organic material. Use whatever you can get. It’s just like what you eat. So if you use a mulch that has more components, you’re going to get more benefits but anything is better than nothing and the old idea that eucalyptus mulch is bad, are unfounded. It has been studied quite extensively used as a seed media, used as a potting media, used as a mulch and it has been shown has no detrimental effects on your plants. Be careful of Oak mulch which may have oak root fungus.

Compost worm castings provide humic acid which helps improve drainage. It decomposes quickly but it should be viewed more as fertilisers than soil modifications. A lot of research has been done by Garry Bender recently on the benefit of compost and preventing Avocado rootrot and the use of mulches on your soil are antagonistic to phytophthora which is the rootrot causing fungi that kills avocadoes. It doesn’t kill the phytophthora but it improves the root system of your avocado so that the symptoms of root rot are not so severe and avocados will often grow faster and produce more roots more quickly than the phytophthora can kill so producing a healthier eco system and healthier plants. In your soil there are harmful organics like phytophthora but there are also beneficial organisms like mycorrhiza and this has been the subject of much research done in the past 20 years. Mycorrhiza are beneficial fungi that are naturally occurring in most soils and have a very important association with root systems of plants. They greatly expand the surface area and absorbent capability of root systems and are incredibly beneficial in enhancing the ability of the roots of plants to absorb phosphorous from the soil; it improves the drought tolerance and improves the health of the plants’ roots. Most native soils have mycorrhiza but if you have a soil that was stripped you may need to reintroduce it to your soil and that’s also true of container soils.

Container Soils were formulated as soil material for growing plants in containers. There is no dirt in container soil and almost without doubt, anytime people put dirt from their garden and adding it to a pot, it will fail dismally. Why? Because you are introducing a lot of pathogens at that time and because the media compacts and when this happens you lose aeration and drainage, the mineral component of dirt is such that it’s not uniform and particles fit together like jigsaw puzzles impeding drainage, and without aeration and drainage, water and air, roots will die. Container soils are made out of products to give roots of plants good aeration, good drainage and water holding abilities and nutrient availability but container soils were never intended to be long term. If Garry were here, he would talk to you about soils and tell you that most container soils on the market today are … in a bag and he would also tell you that most container soils will lead to the death of your plant because he will argue that all container soils today are made principally of 75-80% organic material mostly in the form of wooden bark product and that those wooden bark product decompose and as they decompose, the soil compacts which then impedes air movement and water drainage and roots rot and plants die. Container soils were never meant to be long term. They were meant as a growing media from the time the nurseryman produced the plant until you put it in the ground at home and it not only takes most container soils a couple of years before that organic component breaks down to a point where it causes problems. I’m sure that most of you have had potted plants where you start out with a nice full potted plant and over time, it’s only half full of dirt. The dirt didn’t wash out; it decomposed and compacted and that’s the problem with most potting soils. Most commercial potting soils are pretty good; but there are also bad ones. There have been a number of studies on commercial potting soils: Super Soil, Patio Plus, Dr. Earth, EB Stone, Uncle Malcolm etc. are very good potting soils and they’re formulated out of components that are intended for good root development but they all decompose over time. Some also add organic fertiliser. Are they better than those that don’t? No, it’s just another way of fertilising. Some also add mycorrhiza. Because most potting soils are made up of sterile material, there are no mycorrhiza in most potting soils so a potted plant does not have the beneficial association with the fungi so we need to inoculate the soil in order to get that development of beneficial mycorrhiza. Mycorrhiza is amazing – not only does it improve the drought tolerance in the plant, water absorption capabilities, the abilities to take up fertiliser and also ecto-mycorrhiza which live outside of the roots protect it from many harmful fungi and bacteria because this fungi coats the outside of the root when fungi that normally attack roots of plants come and see roots which are covered in beneficial mycorrhiza they don’t see the root of the plant, they see the beneficial mycorrhiza and they don’t attack the root because they don’t know it’s there so the presence of the mycorrhiza on the roots are protecting that plant from harmful fungi by association. They have also just recently shown some amazing film footage using an electron microscope where mycorrhiza is not just a passage as we thought it once was. Mycorrhiza is a fungus and fungus rely on plants and animals for their nutrients. Most mycorrhiza will invade the roots of the plants and take nutrient from the plants to survive giving the plant back benefits but they find that mycorrhiza also in certain cases are actively killing soil organisms like nematodes. Mycorrhiza can produce a network of filaments that entangle nematodes and noose-like snares and strangle these nematodes killing them and as the nematodes decompose in the soil and die they become nutrient sources for these mycorrhiza – pretty amazing stuff! Adding mycorrhiza to your potting soil can be hugely beneficial and the time to add it is at planting time because mycorrhiza lays in a dormant stage until it comes into contact with the root and once it comes into contact with the root, it can grow and invade and colonise that root. The plant only needs to be inoculated once. You can buy mycorrhiza alone and inoculate the plant or you can buy soils that have the mycorrhiza in it and you can buy other additives.

If you have really bad drainage and want to put in raised beds, what do you do? A raised bed is a container. For long term growing in containers or in raised beds, you want to use a media that does not decompose or decomposes very slowly. The best potting soil or media in which to grow long term is one that does not break down and decompose causing root rot issues. That means we have to use a media that is either primarily inorganic material or is organic material that is either already highly decomposed. Pumice, decomposed granite and quartz sand for drainage. The problem is that all these things are heavy. Garry Matsuoka has a formula that he uses for most of his nursery plants and it’s 40% pumice, 40% peat moss and 20% perlite. The problem is that it drains really fast and it is really heavy but it doesn’t decompose so is satisfactory for long term container growing in raised beds. I would use something along those lines. You can mix in different proportions but peat moss does not decompose much because it is already decomposed. Rice hulls take up to 10 years to decompose and one potting mix I’m familiar with called Patio Plus by Kelloggs has the primary organic component of rice hulls v wooden bark chips which decompose in 3 years. If you’re going to grow long term in containers and use these types of fast draining potting soils with little organic material like Garry’s 40% pumice 40% peat and 20% perlite, you’re going to have to water at least every other day and sometimes every day and they do require mulch on the top of the soil.

I wouldn’t use Perlite in the ground as it tends to float – pumice is better.

Drainage is imperative  Dig a hole 2ft deep and fill it full of water twice. If it drains in 12 hours, or less, you’re fine. If it takes more than 12 hours to drain, you need to go to raised beds or containers or put in drains. 

Rock Dust takes a very long time to break down and add any nutrient value.

Note from Sheryl:   One of the guest speakers failed to turn up at the California Rare Fruit Growers Conference so Tom stepped in and this talk was totally impromptu!

TOM DEL HOTAL, a nurseryman for 37 years, holds 4 advanced certifications from the California Association of Nursery Professionals. He is also a certified Arborist, a certified pesticide applicator, and a member of the International Plant Propagators Society. He currently works full time at the Home Depot in Lemon Grove as a sales associate and as district trainer for the garden department. He is also a part-time horticulture instructor in the Landscape and Nursery Department at Southwestern College in Chula Vista. In addition, Tom has also restarted his own business / nursery “Fantasia Gardens”. Tom has been a member of the California Rare Fruit Growers (CRFG) for the past 26 years and an avid grower of a great variety of fruiting plants on his property in Lemon Grove. He is a past president of the San Diego Chapter of the CRFG and worked for Pacific Tree Farms as the manager and propagator for more than 12 years. Tom is an experienced lecturer and speaker and gives many presentations to gardening organizations as well as at fairs, seminars and special events.

Australian Soil Resource Information System –  www.asris.csiro.au

ASRIS provides online access to the best publicly available information on soil and land resources in a consistent format across Australia. It provides information at seven different scales (view animation).

The upper-three scales provide general descriptions of soil types, landforms and regolith across the continent. The lower scales provide more detailed information in regions where mapping is complete. Information relates to soil depth, water storage, permeability, fertility, carbon and erodibility. Most soil information is recorded at five depths. The lowest scale consists of a soil profile database with fully characterised sites that are known to be representative of significant areas and environments.

Article compiled by Sheryl Backhouse

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Most people know that it is beneficial to have high levels of organic material in their garden soil, whether it is in an orchard, or a vegetable or ornamental garden. Digging in different materials such as compost, animal manures or green manures helps increase the levels of organic matter, and thus, the soil’s biological activity and fertility. The improved soil allows water to penetrate efficiently, supplies nutrients slowly to root zones of plants, and helps root development. In addition, the higher number of organisms such as earthworms helps cultivate and improve the soil.

There is a simple ‘home garden’ way to test the amount of organic matter in your soil. You will actually be testing the ‘biological activity’, which is a direct result of the level of organic material. The test could be used to help to tell whether the organic materials you are adding are having much effect, how long their effect takes to decline, or whether you might have some areas in your garden that are much lower than others in organic matter. 

The test is based on the length of time it takes for soil organisms in the soil to rot a piece of fabric. Where there is a higher level of organic matter in the soil, there will be a corresponding higher level of micro-organisms or ‘activity’, and the fabric will rot faster. The level to which the fabric has rotted over a given period of time is measured by a simple ‘load-bearing’ test.

The test is undertaken as follows: Choose several areas that you want to measure. For example, you might want to compare the results of one garden bed where you have added mulch recently, to another that you have added nothing to for a year, and see what the difference is in biological activity. Or you might have different garden beds where you have added different types of material, and you want to compare which is the better soil treatment.

Take some pure cotton fabric such as an old sheet, and cut it into strips about 30cm long and 3cm wide. Try to make them all the same width, for accuracy of results. Using a waterproof fabric pen, label one end of each strip with the information you want, such as the date, and area of the garden, and what type of organic material has been added. Push a sharp spade into the selected area of soil, to about 15cm deep, to make a slot in which to insert the cotton strip. Fold the strip in half over the blade of the spade and use the blade to push it back into the slot you have just cut. When you draw the spade back out, a couple of centimetres of fabric should be left protruding out of the soil. It is a good idea to take several samples at each selected site.

Leave the fabric in the soil for a period of several weeks, and then remove the strips on the same day. If they have almost completely rotted, they were left in too long, so the test will have to be done again. (If you had several extra strips in the same area, you could remove one each week to see how they are going). The higher the level of biological activity in your soil, the more the fabric will have rotted, and therefore, the weaker it will be. To test the strength of the partially rotted fabric strips, you simply fold one strip over the handle of a bucket and use it to raise the bucket just a little off the ground. Slowly pour water into the bucket until the strip breaks. Measure the amount of water in the bucket with a measuring jug, and record the results, along with the other information that you had written on the fabric. If you have taken several samples in the one area of garden, you can average the results for a better level of accuracy.

This technique can give you useful information about the amount of organic matter in your garden soil, especially if you repeat the test over a period of time, and collect and compare the resulting data.

This article was contributed by Jenny Awbery.

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Scrub itch is the irritation caused by the bite of a small orange-red mite called a Trombiculid larva.  This animal is the same animal order as other mites and ticks (Acarina).  Various species are found around the world and are known under various names as Harvest Mite, Chiggers or Velvet mites.

Around Brisbane the mite is active in the summer months in all rainforest areas, particularly above the 300m altitude, where rain is more frequent during this period.  The parasite is located as far south as the Dorrigo Plateau and northwards along the Queensland coast into New Guinea.  North of Cairns and into New Guinea, the parasite carries Scrub Typhus, a potentially life threatening complication of the bite.  To date, no one bitten south of Townsville has suffered this problem.

Eggs are laid in the soil and, on hatching, the larvae, which are 0.2mm long and scarcely visible to the human eye, climb up grass or other low vegetation.  When an animal, including man, brushes past the plant the larvae drop and, if successful, land on fur or clothing whence they scramble to secluded areas or high perspiration zones.

Typically, humans are bitten at sites where the mite can get entry: the collar line, belt line and tops of the socks.  The favoured sites are the armpits, pelvic region and calves of the legs.  The mite secretes a saliva which dissolves the upper layers of skin – the resulting fluid being sucked up.  This process rapidly produces a very itchy, angry, red lump with the mite continuing the process for several days.

Itching, or abrasion, can cause secondary infection, or possibly it causes the mite to relocate to another site and the process recommences.  After a few days of feeding, the larva drops off and for the rest of its life cycle is no longer parasitic on warm-blooded animals.

Prevention is the best recourse and our local pharmacist recommends using Citronella Oil or Tea Tree Oil, available in over-the-counter Preparations of “Bushmans Extra” and “Walkabout”.  The liquids must be applied to the skin at places where the mite can gain access.  Putting these fluids on clothing seems to be ineffective, but a past recommendation of soaking clothing in Dibutyl Phthalate was considered an effective repellent.

If you have been bitten, then an over-the-counter lotion is Ascaboil, which will kill the mite, as will dabbing with kerosene, petrol or alcohol, but these fluids might produce their own reactions.  If the itching is really severe, then medical advice might be necessary and the best relief will be to take some antihistamine orally.  Rubbing anti-itch creams on the lumps is more likely to aggravate the skin reaction.  

Finally, the best procedure is not to go into rainforest when the mite is active, but, if you do, wear a broad-brimmed hat, do not get off the path, do not brush against vegetation and do not sit on the ground!

Enjoy collecting those rainforest fruits but be prepared to repel these mites over the summer period.

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A new book out in 2005 published by Hyland House which I borrowed from our library and can highly recommend. “Just Nuts” by Allen Gilbert who lives on Bruny Island, Tasmania.  Anyway, take a look at the book as I found it interesting. A number of nut trees available to us in the sub-tropics are featured along with other more temperate types. Now I know that perhaps one of the reasons why our Pecan hasn’t set well for the last 5 years:  It says the climate is too warm!  

Also mentioned in Allen’s book was the Quandong Santalum acuminalum which needs a host plant in order to propagate. Because of the parasitism needs of the Quandong, propagation has been difficult and it is only recently that there has been some success using a common grass species for the developing seedling to parasitise. However, the seeds can be germinated quite readily before being placed with a host plant.

Propagating the Quandong plant can be done using uncracked nuts but one of the problems has been the amount of bacterial and fungal organisms adhering to the shell surface or naturally occurring in soil mixes; these often infect the developing seedling or tend to cause the kernel to rot. For best results it is best to crack open the nut, extract the seed and then clean it thoroughly with a bleach or antiseptic material before rinsing with pure, clean water.

Put the seed in a sterile medium (steam if necessary) such as palm peat, perlite or peat moss insided a plastic bag or in a pot and place the container in a warm, dark place. Allen has used a sealed plastic bag containing damp but not wet peat moss and placed the plant material in it with good results. Seed germination can also be assisted with the use of plant auxins such as Gibberellic Acid but these materials are not readily available to home gardeners. Seeds (kernels) should germinate within 3-8 weeks of sowing and can then be transferred to pots. Whole seeds may take over one year to germinate as the seed coat has to break down and there may also be some seed germination inhibitors within the shell that prevent fast germination.

Once germinated the young plants are best transferred into a pot containing the root of another plant as a host. I’d never read what the host was exactly but Allen says that couch grass and lucerne are two plants that have been used in pots containing the seedlings. The potting mix used should be low in phosphate as too much will kill the plant. The developing roots are very sensitive and care must be taken when transferring the germinating seedling in the pot. The pots used to grow plants should be deep, not squat, as the roots of seedlings are vigorous and grow deeply.

Once seedlings have developed, they can be grafted with a selected scion cultivar but because the stems of the plant are usually thin, some grafting methods are unsuitable. In the wild, Quandongs grow by seeding so there is naturally a large variation within the species. 

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Pruning is required to maintain the shape and size of the plants as they can quickly become unruly and top heavy. Pruning also enables access to the plant which assists harvesting. Care should be taken to dispose of the cuttings as they have the potential to become weeds.
Refer to the Pitaya Growing Note – FG1 for more information.

Step 1 – Before: Pruning should occur after the last harvest in May-June.

Step 2 – Clean main stem: Branches growing up the main stem must be removed.

Step 3 – Remove old growth: Selectively remove the older branches from underneath.

Step 4 – Cut back clean: Cut branches back to the original stem.

Step 5 – Set canopy size: Keep at the most 50 main branches leaving only 1-2 sub-branches per main branch.

Step 6 – After: Pruning is needed to maintain fruit production and size ready for September-October flowering.

Varieties: There are no varieties in the proper sense, but there are many clones which can differ in the stem type, colour, fruit shape, skin thickness and scale expression. There are however two different species, H. undatus which has white flesh and H. polyrhizus which has red flesh. There are also several other fruiting cactus genera that are called ‘pitaya’ one of these is Selenicereus megalanthus which has smaller fruit with yellow skin, white flesh and clusters of spines on the fruit that brush off when ripe.

DEPARTMENT OF PRIMARY INDUSTRY, FISHERIES AND MINES, Crops, Forestry and Horticulture Division, GPO Box 3000 Darwin NT 0801
Tel: 08 8999 2357  Fax: 08 8999 2049  Email: horticulture@nt.gov.au   Web: www.nt.gov.au/dpifm

Disclaimer:  While all reasonable efforts have been made to ensure that the information contained in this publication is correct, the information covered is subject to change. The Northern Territory Government does not assume and hereby disclaims any express or implied liability whatsoever to any party for any loss or damage caused by errors or omissions, whether these errors or omissions result from negligence, accident or any other cause.

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Conventional Mix

20 litres Peat Moss,  20 litres Vermiculite – Grade 3,  120 gms Superphosphate (grind to a powder)

90 gms Lime or Dolomite,  27 grams Sulphate of Ammonia (grind to a powder), 7 gms Trace Element Mix,  9 gms Sulphate of Iron

Organic Mix

20 ltrs Peat Moss,  20 ltrs Vermiculite – Grade 3,  70 gms Guano,  60 gms Dolomite

10 gms Organic Potassium (grind to a powder),  1 ltr Blood and Bone

Guano and Organic Potassium are available from Nutri-tech Solutions – Ph:  07 5472 9900

Wet mixture in a bucket before filling pots. Pots need to be sterilized before use with a 3:1 water/chlorine solution. Seed should be soaked in water for 24-36 hours, changing water as it discolours, before being planted no deeper than 10mm. This soaking allows faster germination, replacing the moisture removed in the drying process. Pots should be placed in a shadehouse, 30%-40% shadecloth is ideal and protected from rain. Bench tops made from mesh are ideal to ensure good air circulation around pots. An easy way to rain-proof your shadehouse is to buy “builders film” from any hardware store and fix under the shadecloth with short lengths of thin gauge wire. The biggest danger to seedlings is from being too wet; wet conditions encourage Pythium and Phytophthora so seedlings should be damp not wet. I find that one watering a day in the morning is sufficient. If a small number of seedlings are being grown, then best control is gained by hand watering. If an overhead system is used, then turn it off just as the water starts to drip from the bottom of the pots. The fertilizer in the conventional mix should last 4 weeks if the seedlings appear a little yellow then a dose of soluable fertilizer such as Thrive will help. Email or call if you need help.

Red Lady Papaya seed from Garry Grant called RB5

It throws both bisexual and female seed.

The bisexual flower is about 3 inches long and is skinny.

The female flower is about 2 ins. long and is short and round.

Bisexual fruit is thin, long and has a smaller hole in the centre so professional growers prefer them because they give more weight but they are also more tropical so they won’t perform in a colder climate whereas the female is more cold tolerant. They also have a different flower. For the backyard, it is better to have one bisexual and two females so you can hand pollinate.   

About Hybrids

Hybrids are the result of crossing 2 “fixed” (stable) parent lines. Hybrids are more vigorous than their parents, produce more fruit and are less susceptible to disease. All papaya are affected by climatic changes but when grown under stable conditions hybrids are very consistent in fruit shape and size. Hybrid seed for sale here is only the first cross of the parent lines, producing F1 hybrids. Hybrids cannot be successfully grown from seed collected from F1 fruit and will be inconsistent in shape, size and yield.

Bisexual papaya are affected by a condition known as carpellody or “cat-facing” and is caused by the fusing of the ovary and stamens during adverse weather conditions. This fruit is deformed and unmarketable. Carpellody is one of the reasons bisexual varieties are not normally grown in sub-tropical areas.

With dioecious varieties growers generally plant 4 seedlings to the site, thinning sites to 1 male site to 10 female sites. Planting density varies between growers but on average is 750 sites to the acre, or 1850 to the hectare. The amount of seed required is 50 grams per acre or 125 grams per hectare.

With bisexual varieties growers generally plant 2 or 3 seedlings to the site, thinning to 1 bisexual tree per site. Some growers market the female fruit of the bisexual, although the flesh is not as thick. Seed required is 40 grams per acre or 100 grams per hectare.

Germination is tested before dispatch and we guarantee a minimum germination rate of 50%.

Contact:  Garry Grant, 18 Vaughan Road, Darts Creek, Qld  4695     Ph:  07  4975 1317         www.papayaseed.com.au