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When we think of berries, we generally think of temperate zone plants like strawberries, blueberries, raspberries and blackberries. The term berry is defined simply as a fleshy fruit with one or more seeds. By tradition, the term is applied mostly to small fruits. Although the Year of the Berry has concluded, I would like to discuss here a group of Central and South American fruits that could be considered the South and Central American equivalents of our temperate zone berries, the genus Eugenia. The Eugenias belong to the large plant family Myrtaceae or myrtles. The myrtle family includes many fruiting plants, the best known of which is the ubiquitous tropical guava, Psidium guajava. Other genera within the Myrtaceae grown for their fruits include Feijoa, Myciaria, Campomanesia, and Syzygium. The genus Eugenia is exceedingly large. A search of the International Plant Names Index at the Royal Botanic Gardens, Kew gives 235 pages of entries at about 20 names per page. Even allowing for duplications and synonymy, there are more species in this single genus than the entire flora of most temperate zone regions. Many of these, if not most, bear edible berries. At one time, the genus name Eugenia was applied to species in both hemispheres but recently, the Old World species have been separated into the genus Syzygium. I will limit myself here to a discussion of eleven New World species already in cultivation. There are undoubtedly many species not in cultivation worthy of domestication. I’ll leave that to some future intrepid plant explorer. The most common Eugenia found in cultivation is Eugenia uniflora or Surinam Cherry. Other names for this plant are cereza de cayena and Pitanga. Surinam cherry, despite its common name, is originally from Minas Gerais and Rio Grande do Sul in southern Brazil. In its native habitat, it is a tree up to 10 metres in height. In those parts of the United States where it can be grown, it is more commonly seen as a bush, often used for hedges. It is a subtropical plant and when established will tolerate down to -5° C. The fruit are small and prominently ribbed.  When ripe, the colour varies from orange-red to dark red. The darker fruits are said to have better flavour. The flavour is sweet and somewhat resinous. In Brazil, it is used to flavour candies, carbonated drinks and frozen desserts. Surinam cherry is easily grown from seed and plants begin bearing at an early age. However, many sources suggest that for better fruit, it is preferable to purchase grafted plants of known quality. It is tolerant of a range of soil types but performs best in neutral to slightly acid soils with moderate humidity and watering.

Probably the next most common Eugenia in the U.S. is Eugenia aggregata or Cherry of the Rio Grande. The name refers to Rio Grande do Sul in Brazil and this plant, like the one before, is a subtropical. It is a large shrub to 5 metres and when established, also hardy to -5° C. Opinions on the quality of the fruit vary but it is a popular fruit in Brazil for making jelly, jam or juice. The fruit is sweet and dark red when ripe. This plant prefers slightly acid soils and even moisture, being easily damaged if allowed to dry out. Plants are said to begin fruiting at about 5 years of age. It is an attractive plant, whether fruiting or not.

Eugenia brasiliense or grumichama is a tree to 20 metres native to the Atlantic coast of Brazil. It comes in three varieties according to fruit colour, yellow, red and dark vermillion. Fruit are sweet and largely consumed fresh, being produced in great abundance from about 4-5 years of age. Fruit drop can be a problem. The tree is very ornamental and established plants will tolerate temperatures down to about -3° C. It has one of the shortest maturation periods for fruit known, going from flower to ripe fruit in 30 days.

Eugenia luschnathiana (syn. E. dombeyi) or Pitomba is also native to Brazil and when fully grown, a tree 8 metres in height. The fruit are somewhat larger than the preceding three species, orange at maturity and about 2-3.5 cm in diametre. It may be eaten out of hand but in Brazil, is more often made into preserves or juices. This plant does not tolerate freezing temperatures but has the redeeming characteristic of fruiting when still small, suggesting utility as a container plant in warm temperate climates. Seeds are slow to germinate and appreciate high humidity at germination. Mature plants will accept lower humidities but fruiting may be impaired if humidities are too low.

The species that follow are not well known outside of their native regions but are of sufficient quality to be worthy of wider cultivation. Most are native to Brazil with a couple of exceptions.

Eugenia stipitata is mentioned in Julia Morton’s Fruits of Warm Climates as a promising fruit. It is native to the Amazonian region of Brazil and Peru and is highly regarded by local inhabitants. It is cultivated in

Peru to a limited extent with the fruit processed to pulp and exported. There are two subspecies. Eugenia stipitata stipitata is a large tree, abundant in the western Amazon basin, heavily utilized by local residents. Eugenia stipitata soraria is a large shrub or small tree and is the variety cultivated for fruit because of its more manageable size. One major reason for the interest in this plant as a fruit crop is that the fruit are much larger than most Eugenias. Fruit on cultivated plants have been known to weigh up to a pound. Because of its tropical origins, this plant would most likely be suitable for cultivation only in South Florida or Hawaii.

Eugenia pyriformis, known in Brazil as uvaia, is from São Paulo and Rio Grande do Sul. Uvaia is a tree to about 10 metres. As the species name suggests, the fruit is somewhat pear shaped, turning yellow to orange when ripe. Fruit are 3-4 cm. in diametre. It is frequently cultivated in Brazil in home orchards, with the fruit being utilized for sweets.

Eugenia leitonii, is known as araça-piranga or goiabão and is another Brazilian species. It is a tree to 8-14 metres and is found from the south of Bahia state to Paraná in the south. It is apparently a slow grower and appreciates humidity. The fruit is yellow when ripe and sweet but only a thin layer of flesh covers the single large seed.

Eugenia tomentosa or cabeludo is a shrub from the Amazonian region. It grows to 2-3 metres in height. The fruit are 3 cm. in diametre and yellow when ripe. It is utilized by local inhabitants and has seen some cultivation. As its origins imply, it would need humidity and warmth to prosper, making it another species best suited for southern Florida and Hawaii.

Eugenia candolleana is another species with edible fruit from Brazil that I have in cultivation. As the image shows, the fruit is purple when ripe and very edible (personal communication Luis Bacher). Beyond this, I have no information on habit, origin or cultivation.

Three other species I have growing and for which I have little information are Eugenia reinwardtii or Cedar Bay Cherry, Eugenia subterminalis or mulchi and Eugenia victoriana or guayabilla. Eugenia reinwardtii is an exception to the general rule that Eugenias are western hemisphere plants. This plant is found growing in Australia and Southeast Asia, often, as the common name implies, near the seashore. The remaining two species are from Ecuador, a center for tropical diversity in South America. Both bear edible fruit. My plants are still seedlings. Eugenia subterminalis seems to be a vigorous plant, tolerating my hot dry conditions with no signs of ill effects. Eugenia victoriana, on the other hand, has been set back by our winter and is struggling with the low humidity here.

Most Eugenias are from tropical and subtropical areas. They appreciate warmth, humidity and even soil moisture, neutral to acid soils are preferable but they seem to handle some alkalinity here in Tucson. Propagation for most species is from seeds. Some seeds germinate rapidly but others may take many months to appear. Seedlings, especially of the tropical species, are susceptible to thrips at emergence and tip blight from low humidity. While I found no reference to production of plants from cuttings, at least one reference felt it likely to be possible. Grafting of superior clones, at least in the instance of Surinam Cherry, is successfully employed.  I grow my plants in containers because in the ground here in Tucson they are susceptible to grubs, Texas root rot and chlorosis. This might not be a problem in other areas. The above ground parts are not bothered by insects. In humid climates, they will want full sun but in the desert, they do better with filtered light. Regular feeding with a balanced fertilizer is also appreciated. Growth rate is moderate and most species under good conditions can be expected to begin flowering by 5 years of age. If your fruit interest is in variety and like me, you cannot grow temperate zone berries due to climate, consider adding Eugenias to your home orchard. Plants and seeds are available from numerous sources and they are attractive as well as useful. I would be interested in hearing from others who have experience growing these interesting plants. Finally, I would especially like to thank my friend Luis Bacher in Limeira, São Paulo, Brazil for allowing me to use his photos and for the seeds he has sent me over the years of these and many other beautiful plants.  Ref:  1. Fruit of Warm Climates – Julia Morton. 1987   2. Frutas no Brasil – Silvestre Silva and Helena Tassara. 19963. Árvores Brasileiras – Manual de Identificação e Cultivo de Plantas Arbóreas Nativas do Brasil – Harri Lorenzi. 1992  and 4. All About Citrus & Subtropical Fruits – Ortho Books. 1985 

The author of this article Chris Marshall MD resides in Tucson, Arizona and grows arid-zone plants, including cacti & succulents.

Sheryl:  I met Chris when I was their guest speaker last year. His article included photos of the plants mentioned but space does not allow us to include them so check for them on the web or have a look at the Fruit Gardener Magazine in our library. He is looking for Brachychiton seed; particularly chillagoensis and paradoxum. Hybrids, as well as species would also be welcome. He’s willing to pay & has already collected:

acerifolius, acuminate, australis, bidwillii, discolour, diversifolia/populneus, gregorii, megaphyllus, rupestris.

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After attending a weekend of talks at Fairhill Nursery last year where I caught up with Nan & Hugh Nicholson (they wrote that excellent series of rainforest books) Nan mentioned that in certain species of Macadamia the kernels contained traces of cyanogenic glycosides.  This was the first I had heard about toxicity in Macadamias and thought I would go looking for other sources of information to do an article for our newsletter. Our previous Guest Speakers Merv & Elwyn Hegarty also knew about it and sent me some detail on the subject. The final piece of information came while I was attending a lecture by Dr. Ross McKenzie on “Cyanide, Strychnine Bush and other poisonous hazards in the Queensland flora”. He sent me an article that appeared in Australian Vet Practitioner 30(1) March 2000 and to summarize:

Plants in the genus Macadamia (family Proteacae) are endemic to eastern Australia (seven species) and Sulawesi in Indonesia (one specie) (Gross 1995) Macadamia tetraphylla, M integrifolia and hybrids of these species – variously known as the Macadamia Nut tree, Qld. Nut tree or Bopple Nut tree are cultivated in Australia, Hawaii and elsewhere for the edible kernels. Some kernels of these species contain traces of cyanogenic glycosides while the kernels of M. ternifolia and M. whelanii contain significant amounts of cyanogenic glycosides, are bitter and not currently used as human food (Aboriginees would remove the toxins before eating them (Gross 1995).

In the clinical study, thirteen adult dogs of both sexes, various ages and at least five different breeds  developed sudden onset of various combinations of either paralysis, pain in the hindquarters, listlessness, limping 6-24 hours after eating several kernels etc. with one Rottweiler being given 2 tablespoons of macadamia butter.  All dogs recovered within 24 hours.

The close association between ingestion of kernels and the onset of the syndrome in dogs and the consistent signs displayed among cases strongly support the hypothesis that toxicity from a chemical or chemicals in the kernels was responsible for the syndrome. Such chemicals may well be part of the plant’s defence system protecting its genetic material from attack by insects or microbes. The only known toxins in Macadamia spp. are cyanogenic glycosides. In one case where roasted kernels were fed, it indicates that heat does not denature the toxin or toxins.

Given the widespread consumption of Macadamia kernels by humans and the lack of reports of subsequent poisoning, this syndrome appears to be a further illustration of the differing reactions of mammalian species to plant toxins. Dogs and humans for example differ significantly in their likelihood of being poisoned by theobromine in chocolate (from Theobroma cacao) and their susceptibility to N-propyl disulphide and thiosulphates in onions (Allium cepa). Dog owners should be warned not to regard their animals as “small humans”. As M. ternifolia is native in the area where I live, I rang our local Veterinary Clinic which has a large country practice (the Vet is an ex-President of the Australian Veterinary Association) and they said they have never come across this syndrome in their practice. I am a little surprised by this as our “Chuck” (actually – Charles Henry Robert Backhouse – the Bull Terrier) who actually belonged to the neighbour but lived at our place during the day could crack an unshelled nut with his teeth – loved them.

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Merv Cooper bought in a newspaper article on Luo Han Guo with no English name so George being the whiz he is on computers found the following info on the web by Subhuti Dharmananda, Ph.D., Director, Institute for Traditional Medicine, Portland, Oregon    http://www.itmonline.org/arts/luohanguo.htm

Luo Han Guo (luohanguo) refers to the fruit of Siraitia grosvenori, formerly called Momordica grosvenori, a member of the Curcubitaceae. The fruit is well-known for its sweet taste; this plant family (Gourd family) has other members that contain remarkable sweet components, including additional species of the genus Siraitia (e.g., S. siamensis, S. silomaradjae, S. sikkimensis, S. africana, S. borneensis, and S. taiwaniana) and the popular herb jiaogulan (Gynostemma pentaphyllum). The latter herb, which has both sweet and bitter tasting triterpene glycosides in its leaves, is now sold worldwide as a tea and made into an extract for use in numerous health-care products.

Luohanguo has been used as a medicinal herb for treating cough and sore throat and is popularly considered, in southern China, to be a longevity aid. These are the same uses as listed for jiaogulan. Luohanguo has more recently been developed into a non-caloric sweetener to compete with other herbal sweeteners such stevioside from the unrelated Stevia leaf.

From Wikipedia:

Siraitia grosvenorii (syn. Momordica grosvenorii; Thladiantha grosvenorii); also called Arhat Fruit or longevity fruit; is a flowering plant in the Cucurbitaceae, native to southern China. It is the only species in the genus Siraitia and is a herbaceous perennial vine growing to 3-5 m long, climbing over other plants by means of tendrils which twine round stems. The narrow, heart-shaped leaves are 10-20 cm long.

The fruit is globose, 5-7 cm diameter, containing a sweet, fleshy, edible pulp and numerous seeds. The fruit extract is nearly 300 times sweeter than sugar and has been used as a natural sweetener in China for nearly a millennium due its flavour and lack of calories (2,3 kcal per g). It has also been used in traditional Chinese medicine.

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Have you grown Madagascar Beans? They are delicious! They are a form of perennial climbing lima bean, sweet, buttery and easy to grow. The bean is an attractive white with purple speckles. They are hardy in the sub-tropics, and ours has had three crops in a year so far. I will bring some seeds to the December meeting for all to try.  A few plants is all you need – grow them along a fence or trellis.

Authored by: 

Sourced from: 

RFC Brisbane Branch newsletter Dec 2000

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The feijoa is in the family Myrtaceae and is a small evergreen shrub with a spreading habit, usually growing to about 4m in height. It was first collected by Fredrich Sellow in the early 19^th century and described in the mid 19^th century and given the name Feijoa sellowiana. In the mid 20^th century it was formally renamed Acca sellowiana (Berg) Burrett as this was deemed to be more botanically correct. However, its original scientific name is still used today. Common names are pineapple guava, guavasteen, and of course, feijoa.

It appears in Glenn Tankard’s Tropical Fruit book (ISBN 0 670 90205 5) but it is definitely not a tropical plant in the true sense. Feijoas originated from the south eastern area of Brazil and Uruguay which is a warm-temperate to subtropical area. This area has generally poor acidic soils and suffers dry periods. However it is important to note that feijoas grow in the plateaus of this area, ranging from 300m to 1,000m above sea level. A French botanist is credited with introducing feijoas to Europe over one hundred years ago, and I understand that all varieties we have today may well emanate from this one source.

Anyone who has eaten a well grown and modern variety of feijoa will marvel at what a beautiful tasting fruit it is. The feijoa is exceedingly fragrant, with a complex flavour. It has a cream-coloured flesh with a distinctive “star” shape when the fruit is sliced cross ways. Quality fruit, depending on the variety, can be up to 200g or more.

Where do you get these fruit? Unfortunately, quality fruit is very difficult to find in Brisbane. The best fruit I have had was grown in Auckland (NZ) – where I lived in the 1980’s. As part of my then job, I was directly involved in registering, under the NZ Plant Variety Rights Act, two cultivars Apollo and Gemini for commercial exploitation. These were selections from a research project to evaluate feijoas grown in home gardens and orchards in the greater Auckland and Northland districts. In my view the best feijoa was Apollo – excellent eating fruit with reasonable keeping qualities. Since this time new improved varieties have appeared.

I have heard people in Queensland say that they do not like the fruit of feijoas at all and from the quality (or lack of it) I have seen here, I would have to agree. Most feijoas have been grown in home gardens producing inedible fruit. The nursery industry to a large extent, have grown seedling plants for sale as ornamentals for the home gardeners. However, there are a number of named varieties you can buy. For further details on varieties available locally visit Daley’s website at: www.daleysfruit.com.au/fruitpages/feijoa.htm .

I have not grown or evaluated the “local” named varieties but am very aware of Triumph and Mammoth. These both originated from New Zealand but over time some clearly have been mis-propagated and therefore are not always true to label. You can guarantee that seedling plants will have poor fruit, even when grown from seed of well-proven varieties. The message is – be careful where you source your plants from. There are very reputable nurseries who do take great care in propagating material.

I am always on the lookout for feijoas especially in the fruiting season. You can find them in all sorts of public places including parks, large ornamental gardens, streetscaping, on university campuses, and corporate gardens. I know of one huge feijoa tree growing in a private property in Tarragindi in Brisbane that must be 50+ years old. Although it has very small fruit it does not appear to be seriously affected by fruit fly – perhaps a potential source of genetic material for plant breeding. Feijoas are grown commercially (small scale) in Victoria and Southern NSW. There is only one commercial orchard I am aware of in Queensland – it is located in Gympie. It was started about 2 years ago by Kiwis with initial plantings of 300 feijoas and a plan to increase this to possibly 8,000 trees. They should have fruit available next season.

Some varieties of feijoa are self-fertile and others require a pollinator, the general rule is plant at least two or three different varieties. The Daley’s web site (see above) will give you good information for each named cultivar. Brisbane does not have the ideal climate and I have found feijoas quite difficult to grow to produce good quality fruit. Feijoas are a hardy plant and apart from them being highly favoured by fruit fly, do not generally succumb to pest and diseases. I have found that feijoas under stress can suffer a fatal form of die back which is symptomatic of phytophthora. They will survive frost. Although they can tolerate drought periods subsequent fruit production is detrimentally affected. To get good fruit the plant needs to be watered deeply; apply superphosphate for flower production (my soil seems very deficient in phosphate); use a good general fertiliser, but do not overdose (I use Nitrophoska Blue TE for all my fruit trees); potash for fruit development; but no lime or dolomite, unless you have highly acidic soils.  I do not use any chemical sprays unless I get really annoyed by the fruit fly. Take note that feijoas are primarily pollinated by birds (I once came across a Northern NSW grower who had planted a few feijoas within a large bird-proof netted area used for stone fruit, and couldn’t understand why he failed dismally to get good fruit set). 

Pruning feijoas is very straightforward. Give them a light prune each year after harvest to avoid excessive spreading and lankiness. Using chainsaws or hedge cutters is OK in my book. This way they will keep a good compact shape and it will not interfere greatly with fruit production. (I like to have plants I can pick the fruit off with out having to climb ladders or use poles). If you leave the plant to grow large and straggly and then hard prune it, you may not see much fruit for a season or two.

Feijoas, depending on the cultivar, ripen from early autumn in Brisbane. They are best touched picked (i.e. hold the fruit in your hand and if it comes away easily from the branch then it is ready to pick – do not yank off) and left for one or two days before eating. Feijoas are not good keepers. The fruit will keep for maybe 10 days in the fridge. Feijoas ripen inside out, and when past their prime or exposed to air the pulp turns a brownish colour with a loss of flavour.

If you want to propagate feijoa plants then the best way is by cuttings taken at the end of the growing season in mid to late summer. Use fresh cuttings straight away; do not let them dry out. Use rooting hormone and put them in a coarse sand and peat type mix. Cover in some form of propagation tent and mist regularly, they will take 2-3 months to strike. They can be grafted with some difficulty, using the whip and tongue method gives best results. Make sure the scion wood is the same size as the rootstock to gain a close fit as is possible on the cambium layers. Grafted trees will generally bear fruit in three years and reach “stable production” in five years.

Feijoas are a healthy choice being low in kilojoules, rich in vitamin C, and are a good source of general vitamins and minerals. The flower petals are very edible and can be used in salads. The native South Americans infused the leaves as a medicinal drink. For the budding enologist – it apparently does make a very acceptable wine. Feijoa pulp can be mixed with ice cream or yoghurt to make a very nice desert.   In fact feijoas can make a good substitute for recipes requiring stewed apples. Use lemon juice to stop the flesh from browning.

A recipe book is available for $9.95 from the NZ feijoa web site at www.feijoa.co.nz – click on “recipe book”. The site also has a very interesting free recipe for how to preserve feijoas for later use.

If you are interested in feijoas there are many web sites you can search on the Internet. A book I would recommend is – Thorp & Bieleski, 2002: Feijoas – Origins, Cultivation and Uses, Hort Research NZ Ltd & David Bateman Ltd – (ISBN 1-86953-503-0).

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This article has been modified for the southern hemisphere.

When we think of lychee trees what we think of is the spectacular evergreen foliage and the clusters of delicious red fruits. What often is not considered is occurring below ground in the root system of the tree. A healthy root system is essential for growing a healthy lychee tree. Understanding how the lychee root system works can help you grow more vigorous and productive trees.

Two Types of Root Systems   Lychee seedlings and grafted trees that have reached maturity have well developed vertical tap roots that can extend a few meters down into the ground towards the water table. These deep dwelling tap roots are accompanied by some lateral branching surface dwelling roots. Air layered trees have no main tap root and instead have entirely shallow lateral branching root systems often called skeleton roots. These skeleton roots have their entire network in the top layer of soil to a depth of about 20cm. The lateral absorptive roots of a lychee tree extend out to about the drip line of the canopy. The diameter of the canopy is a good indicator of the extent of the root system. A clear above ground indicator of a healthy root system is the ability of a tree to resist lateral pressure, such as wind. This is especially true in small trees. Trunks that easily flop from side to side or feel loose, when they are pulled on, are either not healthy or lack an adequate network of roots to support the tree. If some of the root system is exposed, mature healthy roots should be flexible and should display a light green when gently scraped. The smaller branching root tips should be whitish and flexible and should not easily fall apart when tugged. The root system of a lychee tree typically experiences 3 climaxes of growth each year. Not surprisingly, these root system growth events seem to occur when the surrounding soil is warm. They occur from mid-November-December, January-February after harvesting, mid-April when autumn shoots get matured.

How the Lychee Root System Works    A lychee tree has two basic functional systems: the canopy and the root system. It is important to understand the interactions between these two systems and the role of these systems in the health of lychee trees. The canopy, consisting of branches, stems and leaves is where photosynthesis occurs. The products of photosynthesis – sugars and amino acids – are conveyed through the bark to the roots, growing tips of stems and leaves, flowers and fruits. The root system is where water, minerals and nutrients are absorbed from the soil and conducted to all other parts of the plant. Gas exchange also occurs in the root system. The area directly adjacent to the absorbing roots is called the rhizosphere. In a natural, undisturbed forest environment this area is composed of weathered minerals and deteriorating organic matter. Living within this mix are populations of earthworms, insects, diverse invertebrates, protozoa, bacteria and fungi. These organisms participate in the breakdown of organic material into essential inorganic elements that may be used by forest plants. Bacterial microbes break down and solubilize minerals such as phosphorus for plant availability, recycle nutrients and help to protect the plant from soil pathogens and nematodes. Beneficial Mycorrhizal fungi colonize the fine absorbing roots of trees to derive most, if not all, of their food supply (carbohydrates, vitamins and amino acids) from the roots of the plant. In return the mycorrhizal fungi aid in the growth and development of their host tree by significantly increasing the absorptive surface area of the roots, as well as assisting in the decomposition of organic matter. These Mycorrhizal fungi enhance the tolerance of plants to drought, seasonal temperature fluctuations and pH balance as well as minimizing the negative effects of transplant shock. Mycorrhizal fungi also help to protect the plant from harmful diseases and pathogens and reduce the dependency of plants on supplemental fertilizers. In artificial soils, such as what we purchase and use for growing plants in containers or in man-made or urban developed landscapes, these natural soil components are missing and should be replaced for healthy plant growth.

Root shading and cooling:  During late Spring, Summer and Autumn in the sub-tropics the shallow root system of a lychee tree is exposed to the daily cyclical extremes of heating and cooling. This stress is especially pronounced during the mid summer post harvest months. Although lychee trees need partial to full sun, the roots prefer to be shaded for optimum health and growth. The hemispherical habit of growth and shape of the lychee tree naturally keep the root system shaded under the canopy. Mulching provides an excellent way of maintaining a healthy growing environment around the absorbing roots of a lychee tree. Mulch retains moisture, promotes and created a home & food for beneficial soil bacteria and mycorrhizal fungi, earthworms, insects, protozoa and effectively shades the root system from direct exposure to the sun. This helps to regenerate the soil around your lychee tree to approximate forest soil characteristics which are missing in artificial landscapes.

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Jackfruit mature 3 to 8 months from flowering.

A dull hollow sound is produced when the fruit is tapped with your knuckle.

The last leaf of the peduncle yellows.

Fruit spines become well developed and wider spaced and soften.

The spines yield to moderate pressure.

An aromatic odour develops.

Picking time depends on whether the fruit will be used at home or sold.

Fruit intended to be eaten soon should be harvested when the rind is fairly soft, the peduncle leaves turn yellow and the fruit has an aromatic odour.

Fruit intended for sale should be firm with no aroma but the leaf nearest the fruit must be starting to turn yellow and the spines set far apart. The flesh at this stage is crispy and pale yellow.

The quantity of latex decreases as the fruit ripens. Try to cut a fruit that is green and you will have latex all over you. Cut into an over ripe fruit and there is almost no latex.   If you do get the sap on your hands you can easily get it off using lanoline soap, the kind they use in industry.

After ripening, they turn brown and deteriorate rather quickly. Cold storage trials indicate that ripe fruits can be kept for 3 to 6 weeks at 52° to 55° F and relative humidity of 85% to 95%.

You can also make 3 shallow cuts in the fruit a few days before you plan to cut it down which will let some of the latex drain out.

Use rubber surgical gloves and coat knives with olive oil when cutting up the fruit just in case of latex.

If the fruit is too high up to check if it is ripe, slap it with a long pole to hear that dull sound.

Ripening can be accelerated by putting whole fruit into a closed 20 litre bucket 5-7 gallon (20-30 quart)

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Anthracnose is the primary reason why mangoes, avocadoes and some other fruit trees fail to fruit or develop blackened fruit that drops prematurely. Anthracnose is a fungal disease that is exacerbated by rain and high humidity. During dry weather the disease is virtually absent. Application of copper based sprays immediately prior to flowering and during early fruit set and/or use of biodynamic preparations such as casuarina tea can help reduce the effects of anthracnose. Some fruit tree varieties also possess inherent resistance to anthracnose.

Black Spot on Pawpaw

Adequate nutrition is as much a tool in disease control as the use of sprays. Plants deficient in potassium, phosphorous and magnesium are more susceptible to attack by black spot and powdery mildew. Simply increasing the potassium (sulphate of potash and/or lucerne mulch), phosphorous (rock phosphate or chicken manure) and magnesium levels (Epsom salts) helps to make plants more resistant to disease. Pawpaws are most susceptible to black spot disease during the cooler months. Spraying with sulphur or copper based compounds prior to the onset of the cool weather and watering with liquid seaweed can help reduce the severity of infestations.

Citrus Melanose

This disease typically affects more mature trees or plants that have a canopy of foliage that hangs close to the ground. Mulch trees with a feeding mulch such as lucerne. This will help to prevent spores splashing up onto the foliage when it rains. Lift the lower branches so that foliage is well clear of the ground. Spray trees with copper based compounds after all fruit has been harvested, thoroughly wetting the foliage, trunk and branches. Repeat applications each year until no further evidence of disease exists. Improve general tree health with additional nutrients and water.

Damping off Fungus

This disease affects germinating seeds and young seedlings. It is transferred via water and affects the water conducting tissues of the plant. Use new seed raising mix or clean compost. Wash all pots and tools in hot, soapy water then allow to dry in the sun before use. Make sure that plants do not sit in water. There is no cure for affected plants and they should be disposed of so as not to infect neighbouring stock. Note that newly planted seedlings can appear to suffer from a similar condition, but this is typically the result of over watering or planting into a soil containing excessive amounts of fertiliser or overly rich compost and manure.

Passionfruit Virus

At the end of the growing season after production of a bountiful crop, passionfruit vines can look tired and in need of a well earned rest. In some cases, vines will show characteristic mosaic leaf yellowing that indicates presence of a virus disease. Such diseases are often present in plants from an early age, but only begin to gain the upper hand when the vine is occupied with fruit production or stressed in some way. Affected vines may continue to grow, flower and fruit in coming seasons, but will always lack vigour. Unfortunately there is no cure for virus affected plants. Given their rapid growth rate, high productivity and short lifespan, passionfruit vines are best replaced every few years. Unfortunately there is no cure for virus affected plants. Given their rapid growth rate, high productivity and short lifespan, passionfruit vines are best replaced every few years.

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This is a system that uses an open vertical or near vertical pipe to deliver irrigation water to the deep root zone. It encourages a much larger root volume than other forms of irrigation and helps develop a plant that is better adapted to survive after watering is terminated. By delivering irrigation water through deep pipes rather than on the surface, tree roots tend to grow down rather than at the surface which can also benefit any intercropping annuals which tend to be shallow rooted. Weed competition is reduced by avoiding surface irrigation. Deep pipe irrigation works just as well on steep slopes as on level ground.

It is done with 2.5 – 3cm diameter pipe placed vertically 30-50cm deep in the soil near a young tree 2.5-7.5cm away for seedling trees up to 12cm away for larger trees. A screen cover of 1mm mesh can be added to keep animals out. Several pipes can be used for a larger tree if necessary arranged around the tree symmetrically. A series of 1-2mm holes should be spaced 5-7.5cm apart down the side of the pipe nearest the plant to allow water to weep into the soil at all levels (not only at the bottom) to facilitate root growth early on.

If shallow-rooted plants from containers are planted next to a deep pipe without weep holes, the roots may not make contact with the wetted soil. Similarly, a young seedling can dry out if a drip emitter is used to deliver water into the pipe even if it has weep holes. Growing plants in deep containers can minimise these problems.

Deep pipes can be filled from hoses, watering cans or fitted with a drip emitter. If a drip emitter is used then the deep pipe can be smaller (down to around 1cm diameter) and in order to ensure that the water seeps through the pipe at all levels, the drip water rate must be fast enough to fill the pipe or alternatively, the pipe can be tilted with the weep holes downwards so that the water runs over and through them. A battery-powered remote timer combined with a water tank can be set up at a remote site to irrigate once a week which should lead to good tree survival.

The advantages over buried drip systems include ease of access to the drippers in case of blockage.  Deep pipe irrigation can be used with low quality water (though not necessarily with drip emitters if they are likely to block up). The deep pipes can be collected at the end of the season for re-use. Experiments have demonstrated that deep pipe irrigation systems are very effective and more efficient than surface drip or conventional surface irrigation. Much larger effective rooting volumes are developed and the plants are better adapted to survive future dry spells. In very dry regions, long term survival and growth can be improved by including micro catchments to increase effective rainfall by the use of tree shelters to reduce water demand and by the use of mulches.