Papaw / Papaya / Pawpaw Tips

  • Yes ... Papaw is technically the correct spelling here in Australia!    Feed monthly with lime and potassium.
     
  • I grow papaya commercially; by far the best variety is 'Red Lady'.  This has 13 % sugar.  The seeds are expensive but you can sell this variety at a premium price owing to its superb flavour.  This is an F1 variety and must be grown from new seeds.  If you plant F2 seeds from your own fruit you will get rubbish which will become virus infected very quickly, 'Red Lady' is virus resistant. The seeds are supplied by KnownYou Seeds of Taiwan about $300 for 100 grams, the seeds are very small and should be planted individually (just one) in a litre black bag.  You will get almost 100% germination and 10 grams is sufficient to plant one hectare.    Ref:  David Chulow – Venezuela
     
  • Boron Deficiency  The fruit of boron-deficient Papaw are deformed and bumpy due to the irregular fertilisation and development of seeds within the fruit. Ripening is uneven and the developing fruit secrete pinkish white to brown latex. Heavy premature shedding of deficient male tree flowers and impaired pollen tube development can lead to poor set in the fruit-bearing female trees.  Ref: Plant Nutrient Disorders 2 Tropical Fruit and Nut Crops.   Also:  https://www.ctahr.hawaii.edu/oc/freepubs/pdf/PD-91.pdf 
    https://www.ctahr.hawaii.edu/oc/freepubs/pdf/CFS-PA-4B.pdf
     
  • Member Mark Mammino has a 2 years old tree which was cut back at 1 year because of blackspot. He has changed sprays from copper oxychloride to copper hydroxide - much better result and less toxic. During winter fruit picked at colour change has very good flavour - has already picked at least 10 fruit.  He uses two heavy applications of fertilizer each year; nitrophoska plus terrafirma organic life but doesn’t dig it in. He then places mushroom compost around the plant, plus grass straw over the top and waters only when it starts to become dry as he thinks a lot of plants are over watered. No routine spraying program only on observation does he use copper hydroxide plus an insecticide sometimes if required.
     
  • Ray Johnson says he was talking to Garry Grant the papaya chap who sells papaya seed and he said that to get good flavour in your papaws you must feed them monthly. When they are young with no fruit, put on a high nitrogen fertiliser monthly then when they start to fruit, add three handfuls of something like Organic Xtra or Dynamic Lifter etc. plus a handful of Sulphate of Potash but do this monthly. Cut back over winter to 2 handfuls etc.
     
  • My papaw took a turn for the worse suffering from powdery mildew when it started to rain in winter.Garry Grant suggests a weekly spray from May of 1 part full cream milk and 10 parts water sprayed on. You'll know it's working when you see a scar on the fruit where the mildew has been. Garry no longer sells certified seed but he said most of us don't feed our trees enough. They need 100gm (a handful) of Sulphate of Potash per month which amounts to around 42gms of pure Potassium so if your papaws aren't sweet, it's because they need a lot more Potash. He is certified organic so uses a product by Incitec - 25kg for approx $25.00. They also require nitrogen so use chook pellets or equivalent. If they don't have that healthy green look, that's when they need it! Ref: Sheryl Backhouse
     
  • Fruit rots in pawpaws There’s nothing worse than watching your thriving pawpaw trees grow and produce heavy crops of perfectly rounded fruit, only to see the fruit rotting away to useless mush as they ripen. I know, I’ve been there many times and it pains me to the core. So what’s the cause and how can you stop it? Fruit rots in pawpaws are caused by a fungus. It can infect the fruit when it is still green. Don’t confuse it with the tiny black spots you often see; these are fungal too, but generally cause no damage to the quality of the fruit. You won’t notice the fruit rotting fungi while the fruit are green. They don’t kick into action until the fruit starts to ripen, and then you really know about them, because those sunken lesions seem to appear overnight and rapidly grow as ripening progresses. When the fruit is fully ripe and ready to eat there is little edible flesh left to save. There is a simple solution, ladies and gentlemen. I only learned about it recently while doing some research, and it’s simpler than you would think. All you need to do is submerge the fruit in warm water at 45°C for 20 minutes. I have tried it and it works. The heat kills the fungal spores and stops the lesions in their tracks. After a 20 minute soak, I remove the fruit and leave it on the kitchen bench to continue ripening. Many of the lesions, which would normally grow at an alarming rate simply shrink and came away from the rest of the fruit. What a revelation! Ref:  http://www.organicgardener.com.au

     

  • Papaya are easily cross pollinated. Even at 10 kilometres distance if the wind direction is favorable, papaya flowers if ready can be fertilized from other trees especially males. Insects are also good pollinating agents.   Ref:  Rex – Phillippines  rarefruit yahoogroup
     
  • Male papaya flowers are good source of papain - a tenderizer in cooking meat - gather, chop and dry them and every time you cook meat get a few grams and add to your cooking as a tenderizer.  Ref:   Rex
     
  • Fertiliser   Put Magnesium and Potash on the drip line 6 weeks before fruiting.
     
  • Problem with wildlife   My aunt in Cairns uses black mesh or you can also use insect screen to put over your fruit. She just uses pegs to clip it into place and uses it on her pawpaws.
     
  • I heard Annette McFarlane on radio - Saturday morning 6.30am mention that if you buy some orange balloons, fill them with water, and hang them at the bottom of your ripening papaws, then it should frighten those pesky possums away when the balloons explode.
     
  • Do you grow tasteless Papaws? I’d be interested in someone testing this theory out that I read in an old magazine. An old Chinese gardener in Cairns use to put butchers salt outside the root area then water it in. Let me know your outcome! Ref:  Sheryl Backhouse
     
  • You can use the papaw/papaya seeds either dried or fresh. I usually use them dried in a peppercorn grinder. They really do taste like black pepper. To use fresh just put them in a blender with a bit of vinegar and grind them up small and then add whatever other salad dressing ingredients you want. Really quite healthy and also works as vermifuge (expels intestinal worms).  Ref: Oscar - Hawaii

     

  • In January this year I sun-dried slices of papaw. I put an old baking tray in the bottom of the drying box. The tray had baked on grease that I had previously (unsuccessfully) tried to remove with detergent and scrubbing brush. Five pieces of papaw dropped through the racks onto the tray. After the drying I noticed that the fallen bits appeared to remove the burnt-on grease from the dish. The fallen bits of papaw were blacker than the tray had been whereas those still on the rack were orange. My brother checked the tray out and suggested I clean all my metal cookware with fresh papaw but as yet I haven't given it a go.I have known for a long time that papaw is used as a meat tenderizer and have read that papaw contains the proteolytic enzyme (papain) but the tray appeared to contain just grease (fat) which is a different molecule to protein. I have tried to find out more from the Internet but have come across more nonsense than sense. In the early 1990s I was told a story (possibly an urban myth) about a friend of a friend who consumed papaw and water only for sometime and ended up in hospital with a dissolving stomach. I believe we have some biochemists among us so I'm hoping that they know whether papain is a lipase as well as a proteolytic enzyme and/or more about papaw enzymes and what they catalyse. Ref:  Tirsha Raynlyn
     
  • Changing the sex of Pawpaw – an update by Peter Christensen.  Regarding the recent comments on Pawpaw in the Sunday Mail re: Edwin Menninger’s book “Fantastic Trees” where it mentioned that male pawpaw trees can have their sex changed to female by beheading them, I have previously tried it and it didn't work!  I mentioned this to the local nursery and this was suggested to be a non event. In my case it didn’t work on the male tree that lost its top.  I bought a DPI publication years ago called “Old Ways on the Farm” and it has an article on changing the sex of the papaw in it (Jun 1916). “The method of changing the sex of the male pawpaw tree by cutting it down to about three feet off the ground was accidentally proved in a garden at Milton this season. The owner cut down three male trees and inserted a female shoot on top of each. Owing probably to the very dry weather all these shoots died and two of the trees were rooted out. The third was left and it sent out two strong shoots about a foot below the top. These shoots bore female flowers and three fruits matured one of them remaining on the tree last May as shown in the accompanying illustration.”
     
  • Fertilise with 10:3:6 or organic fertiliser.   Lime with Epson Salts or dolomite which includes magnesium. Sulphate of Potash also beneficial or you could use the soluble Potassium Sulphate – handful to the sq. m.  Ease back on watering. If leaves are yellowing, give Boron - 1g/litre to foliage and soil. Plant out young trees in March as they don’t get too tall when fruit is on.
  • I have read your Feb-Mar newsletter article “changing the sex of papaw – an update” by Peter Christensen.  You might also find the following of interest.  Over 95% male papaw trees produce some hermaphrodite flowers in spring and can set from 5-25 fruit.  They are always a larger shape as are all hermaphrodite (bisexual) fruit and are called ‘long toms’.  The seeds of this fruit give 75% male and 25% female plants.  They are commercially used in breeding programs to produce a purer female line as they result from inbreeding or self-pollination.    Ref: Peter Young
     
  • Eating seed of Papaya   We mentioned in a previous newsletter that you can eat the seed of Papaya. However, there is data that it can make men sterile and it is used as an aborticant in third world countries for women. Just Google.   Papaw seeds are also great as a replacement for pepper corns when making dill pickles.
     
  • I read of a Chinese gardener living on the Atherton Tableland near Cairns who put butcher’s salt outside the root area and then watered it in.  It was done to improve the flavour of tasteless papaws. Test it out and let me know if this method works!
     
  • Male papaya flowers are good source of papain - a tenderizer in cooking meat - gather, chop and dry them and every time you cook meat get a few grams and add to your cooking as a tenderizer.
     
  • Having a problem with black spots? 
    Small black spots = cold
    Large black spots = anthracnose
  • Why some Papaya trees fail to fruit    https://www.ctahr.hawaii.edu/oc/freepubs/pdf/AEC-339.pdf
  • Why some Papaya plants fail to fruit    https://www.ctahr.hawaii.edu/oc/freepubs/pdf/F_N-5.pdf
  • The Papaya in Hawaii   https://www.ctahr.hawaii.edu/oc/freepubs/pdf/B-32.pdf
  • Ariel - Israel   I pulled out a few of my large male papayas with stems of 20-30 cms in diameter and decided to make steaks, from the lower non-hollow stem portion by cutting 1 cm thick slices, added spices, salt and tried it in a microwave for 10 minutes placed in a cookie, fried them in a small oven, cooked them in a bowl with boiling water for 30 minutes.....the result was wonderful! Ariel
     
  • Any papaya propagated from a mature cutting will give fruits from ground zero. When I wanted to impress people, I used to plant my papayas in a 50 cm deep h ole and gradually add the soil and plants then flowered at ground level. As you know the fruit length and petiole leng th are at least 35 40 cms long thus I had to dig again to let the frui ts develop under the soil level! Ref: Ariel Israel.
     
  • Ripening papaya sometimes has a clear jelly like trail on it. Causes? Any clear flow on papaya would be a sap flow I'm assuming, boron deficiency will produce this . Ref: Garry Grant
     
  • Propagation of papaya is mostly through seeds. However freshly extracted seeds show low germination due to presence of sarco testa. Storage of seeds at 10 C was found to be the best for retention of seed viability. Viability of papaya seed can be maintained for 9 months at room temperature when stored in air tight containers. Ref: National Horticulture Board of India http://nhb.gov.in/
     
  • Regular irrigation is an important aspect in papaya cultivation, which helps in growth, fruit development and high yield. Moisture stress inhibits the growth and also promotes male floral
    characters . In general, irrigation to grown up plants is given once in 7 10 days in winter and 4 5 days in summer. The ring system of irrigation has been found very effective. This system helps in preventing collar rot as there is no direct contact between the water and the stem portion. Drip irrigation helps to save 50 60% water. Irrigation through the drip @6 8lit. /day/plant gives better yields. Ref: National Horticulture Board of India http://nhb.gov.in/
     
  • I just watched Daley’s Nursery video on growing Papaya and it looked really healthy! Emailed Greg to ask if it was growing in a hothouse and he confirmed that it was and it’s the Broad Leaf Papaya growing in their Biodome hothouse. It’s very distinctive in its foliage and strongly bisexual.
     
  • Christopher Columbus noticed that the natives in the Caribbean were capable of eating large servings of meat, poultry, fish etc. without any kind of discomfort from indigestion. The inquisitive Columbus later discovered that they were eating unripe Papaya after every meal. Ref: Asit Ghosh
     
  • If the fruits don't have seeds, it means they weren't pollinated. This often happens in commercial fields with the first fruits that are set, when there still isn't pollen available. Seedless papayas are usually smaller, with less flavor and sweetness, than seeded fruits. Although bees and butterflies may visit papaya flowers during the day, most of the pollination is done by nocturnal moths. That is why the flowers are white and fragrant, to attract pollinators at night when colors couldn't be seen. You can do the pollination yourself if you want... it's easy. Just wait until the morning when the female flower opens, get an open male flower, and dust the pollen from the male on the stigma. Ref: Bryan Brunner
     
  • Propagating Papaya Seed   Put fresh seed in water for 24 ho urs, remove any coating and rinse in running water. Dry in the shade. Remove immature seed etc.
     
  • Store Papaya Seed in the refrigerator @ 5C sealed in moisture proof packages. If this is not available, they should be kept in air tight bottles or packed in polythene bags and sealed properly. Store in a cool, dry place.