Monday, July 13, 2020

PAPAYA ( Carica papaya)

This blog has been going nine years now and I am finally brave enough to write about Papaya.  I can even put up a photo of a tree that is doing well in my garden right now.  No way, however, am I an expert.  In fact most of my success with Papaya in the past is from volunteer trees.  They grew on their own accord thanks to a bird pooping out some seed in my yard.  Other volunteers seem to like growing on the side of the compost cage.  I have been learning about Papayas over those years though....trying to find out what magic seems to make them grow and/or just die suddenly on me.  And how come they seem to grow like weeds in someone else's place!

I have been a daily Papaya eater for most of my adult life so you could call me a Papaya enthusiast. The least I can do is share with you what I have gleaned about growing Papayas over the years.  Any extra information you would like to add at the bottom is very welcome.

Papayas are native to lowland tropical Central and South America but are very much part of any tropical fruit growing around the world now. People from the UK and her old colonies often call them Paw Paw but that is very confusing to Americans who have another native fruit bearing tree with the same name which I have seen in the forests of Ohio.  Here in Hawaii, Papayas are often part of our breakfast for locals and tourists alike.  Hawaii is known for a smaller, fragrant Papaya that is just the right size for cutting in half for a one person serving.  They are called Solo Papayas.  Yes, thanks to Google I have only recently found this out.  I would see "Solo Papayas" written on the shipping box and think it referred to a brand or a variety; but no, it is the size!  The native Mexican Papayas are much bigger and longer.  These Solo varieties have also been developed in pink and red flesh types as well as the usual orange.

My favorite Papayas are those grown by Windward Oahu farmer Ken Kamyia such as the Laie Gold variety which have the nicest flavor.  Some will protest that these are genetically modified fruit but most Papayas farm grown in Hawaii are.  It is GM fruit that saved the collapse of the Papaya farming industry from crop diseases.  You are still able to grow you own fruit trees from the seed in a GM Papaya or you can hunt around for a non GM grower if that concerns you.

Papaya trees can grow up to 20 ft. tall.  There is a corona of leaves up top of the single hollow trunk.  Older trees may have lower branches, each with a smaller crown of leaves.  Usually, if you cut down the main trunk the tree will die.  Water gets in that hollow center and rots the tree.  However, sometimes you can save the tree by putting a big coffee can upside down over the cut trunk to keep the rain out and the tree will grow on to provide fruit from it side branches.  Most trees only last a few years but sometimes you will find an old multi-layered one.

Papayas fruit all year round but it takes longer for the fruit to mature in the winter months than in the summer. (26 weeks from flower to ripe fruit in winter,  22 weeks in summer.)  It is usual to harvest the fruit at the "color break" stage.  The fruit get too soft to handle when ripe and then you will also have the birds eating them.  There are long extending poles with fruit pickers attached for the home grower to use..  Or you can go cheap and attach a "plumbers friend" plunger on a bamboo pole to gently harvest your fruit.  My usual way is to just detach the fruit with a long stick.  The fruit hit the ground but I have found that if the fruit is still mostly green it withstands the rough treatment without bruising and I just ripen the fruit up on the kitchen bench for a few days afterwards.

To grow Papaya trees from seed, just scoop out the seeds and leave them to dry for few days until the moist sacs around the seed dry out.  Having them in a semi shaded place is better than in the hot sun and you will need to protect them from birds if you have them outside.  Those cardboard soda trays are really good to dry seed on.  They are absorbent but the seed does not stick like it does to paper.  It will take a few weeks or more for the seeds to sprout in potting mix. 

Papaya trees are not happy movers so it is best to start the seed in 1 gallon pots as opposed to seed trays.  That way they do not need to be transferred into a bigger pot later.  Sow 3 - 5 seeds in each pot and the best will be selected to be the one as they grow.  When the plants are at least one foot high they can be planted out in the garden in the open.  Select a sunny place with some space for the roots to grow without competition.

Selection time!  This is when things get a little tricky.   When you drive past a Papaya farm you will see rows of single trees but all those trees started out as 1 of 3 that were planted out together.  The farmer then selected which tree got to live on.  Sometimes you just see a weakling that is quickly snipped off.  No need to disturb the root system.   But the main reason for selection is the sex of the baby tree.  The farmer will not know the sex of the tree until it is about 3 ft. tall and starts having flowers.  The flowers and sex of the plant can be three different types:  male, female and hermaphrodite/bisexual.  All those nice shaped solo Papayas that you buy at the store are hermaphrodite so that is the ideal tree you are looking for and you only need one so if there is more than one in the pot, select the strongest one..

It is easy to tell which plants are male as their flowers grow out on long  stems away from the tree trunk.  Cut the young tree down at the bottom of the trunk by the ground.  The male trees do not produce fruit....well except a weird few that may produce a few tiny fruit on those stems.  In the old days Papaya were just male and female so you would keep one male tree around to pollinate your females.  I still keep one male tree around in my garden because I love their fragrant flowers.

Male Flowers

Now the trickier part is telling the difference between female and hermaphrodite flowers.  They both appear on the trunk sitting just above the base of the leaves but they each have a different shape.  The female flowers will have  a rounder shape while the hermaphrodite will have a narrow part before the flower. Plus you can see or not see the male and female bits inside the flower.   Google images can help you here as it takes a bit of practice to see the difference.  Once learnt you will be inspecting the flowers of every Papaya tree you see for the rest of your life.  :o)

Female Flowers and Fruit

If you are a farmer you will only choose a hermaphrodite tree to grow on the farm.  If all three little trees turn out not to be one, all three would be chopped down and a new threesome would be planted.  At home you can keep a female tree if you want.  It will have fruit but they are rounder with slight ridges.  Sometimes the flavor will not be so nice, but you do have fruit.  As I said, the hermaphrodite are more popular.and are the ones sold in the supermarket.

Hermaphrodite Flowers and Fruit

Papaya trees like sun, rich soil and need about 4" of rain per month to be happy.  The thing they hate most is wet feet.  The roots quickly get fungal rot in soggy soil and the tree dies.  Good soil drainage is very important.  Papayas do not like temperatures below 60 degrees F. so lowland Hawaii is best.  It can grow in lava or sandy soils with added nutrition.  They do not like strong winds as they have shallow roots and can be blown over easily.  They also do not like the salt winds.  I try to grow my Papaya where they are protected from local ocean winds but once a Papaya tree has grown above the roof of my house it is going to lose all its leaves and die once the windy season arrives.

Papaya trees love organic matter.  Give them a mulch of compost....but remember to keep a few inches of space open around the tree trunk for air movement.  They love old chicken manure, kitchen  scraps, lawn clippings, etc.  They also like high nitrogen fertilizer sprinkled around every few months or you could go with another like 14:14:14.

Apart from root rot because of poor drainage, there are other diseases that can show up.   There is the Ringspot virus that gives yellow mottled leaves and stunted growth.  The GM varieties are resistant to this.  Other diseases that affect the fruit tend to show up in the rainy winter months.  There is Anthracnose  which cause round rotten spots on the fruit and another is a disease that causes "cat face" deformity on the end of the fruit.  This is why it is sometimes harder to find Papayas at farmers markets in the winter months.

I have long been an advocate of Papaya for their nutrients.  It means you can easily get your daily vitamin A and C as well as fiber in your diet.  It consoles me if I do not eat so well for the rest of the day.  I like a ripe Papaya for my breakfast but I also eat green Papaya chopped and cooked in soups and stir fries as well as grated raw in salads.  If I cut open a ripe Papaya and it is not yet soft, I will peel it and cut it into "carrot sticks" to eat that way.  A squeeze of lime or lemon juice on ripe Papaya makes it extra good.  If the  fruit of a certain Papaya trees seems not so tasty when ripe, that is the tree that will provide the green fruit for cooking.  It can also be peeled, seeded and chopped up to be frozen for later meals.

If you look around the internet you will find many other suggestions of uses for the fruit, leaves and flowers of the Papaya.  Many of them are for medical usage.  Of course there is also the Papain enzyme obtained from the sap of the green papaya fruit that is used commercially in making meat tenderizer.  Another reason why you should use green Papaya in your cooking.  It should soften up that bit of tough beef in your stew.

I guess that is about all for now on growing Papayas but no doubt I will be adding info on at the bottom when I learn of another nugget of wisdom.   I do have one more garden hint to add on here.  I have noticed that slugs LOVE  the dead Papaya leaves that fall on the ground under the tree.  If  I am going to go on a slug hunt that night, I will strategically place  dead Papaya leaves around my garden earlier in the day.  That way it is easy to find the slugs that night as they will all be chomping on these leaves later.



  1. What a wonderful blog you have here. So many interesting observations you've made, it's been really nice to read a down-to-earth account of growing many things in Hawaii, along with what you've found in your travels.

    a fellow gardener from Kona

    PS- and you are SO right about papaya leaves (great bait) and slugs!

  2. Thank you cyfo for the kind made my day. Aloha