Paw Paw

I have three Asamina Triloba trees in my backyard in Vancouver. They are not self-fertile but I know that all three are different varieties (one is NC-1; I don't recall the other two).

Two are quite mature: about 5 m tall. But only one of them has ever flowered. And not even every year: every few years it produces several flowers. That is all.

None of the flowers has ever led to a fruit.

I assume that if another one flowered. they might fertilize each other and I would get fruits. But I can't understand why only one will flower, or why it only flowers every few years. Any ideas, anyone? .

 

Asamina triloba grows in places that have hot, humid summers. Our cool, dry summers could inhibit development of flower buds. I wonder if anyone has harvested Paw Paws in the Lower Mainland of BC.

 

UBCBG has ten or so planted ten or twelve years ago. I posted photos of one of the trees this year at August 2018 in the garden. It has not been posted before, and I don't recall seeing it before, so I don't know if any of them have flowered or fruited. VanDusen Botanical Garden has two, from 1973 and 1993; again, I don't know if they get flowers and fruit, but I've asked a docent there.

 

There are some people in Sidney, Vancouver Island growing Paw Paw. They have a YouTube channel: Fruit Trees and More. There is a video on Paw Paw there. If I remember correctly, we don't have the correct insect/bird to pollinate and it must be done by hand.

 

Kevin Kubeck, the Nursery Manager here at UBCBG brought a sack to work last fall from his trees. They were ripe and quite tasty. He said he thought the reason he was getting good fruit for the last 4 years was mostly to do with the trees finally reaching maturity. They are not self fertile, so do need to be cross pollinated by another plant. The pollinators are flies and beetles, so those are the ones to encourage.

 

Thanks, Eric. Do you know if Kevin's trees are grown in the open or in a greenhouse or some other shelter?

 

Eric, pollination by hand is only possible if both trees have flowered, no?

 

Yes, one would most likely need two different plants flowering at the same time to get fruit--self fertile cultivars are rare. I don't know, but doubt that Kevin pollinates his trees by hand. Fertilizer that attracts flies can be applied at flowering time.

 

This past spring they all flowered, two of them at almost - but not quite - the same time. I watched a youtube video about fertilizing them by hand and it didn't look very hard but alas I was a bit late. I have high hopes for the coming spring.

One of them is starting to get very very tall.

 

What is this, that I see
appearing on my Paw Paw tree?

 

The image doesn't show up on my computer.

 

I encountered this problem, when I pasted .../image_name.jpg.html type link instead of .../image_name.jpg. It is impossible to remove or correct this tag later. It does not show up in the edit window.
Even if to write only the tag and post the message, then it is impossible to correct it later.

 

My understanding is that squirrels love the fruit; there is a gentleman in New West that not only grows pawpaw but is able to harvest quantities of them yearly but he says he has a heck of a time keeping the squirrels from the fruit so he puts small wire cages over the developing fruit (not an easy task). And my pawpaws even had fruit developing on them for the first time this year until the squirrels arrived.....no fruit any more.

 

Hopeless. I can't post photos to save my life.

Anyway, I did my best to fertilize some blossoms on each of my three trees with pollen from another tree and to my surprise, 2-3 weeks ago a cluster of fruit appeared on my smallest tree.

I assumed that was all. But yesterday I went out to trim a broken branch that I noticed on the tallest tree and to my astonishment I found 6 clusters of 2-4 fruits all growing well. Some of them I can tell, from their location, were NOT fertilized by yours truly. I reckon some insect done done so.

Out of curiosity, it trees have to be fertilized by a tree of a different variety, every fruit is different from the fruits of the two trees that contributed to its creation, no? Or am I displaying my total ignorance of genetics.

 

Have you had a look at Attach photos and files
If that doesn't help and you can tell me where it goes wrong, I could add a note.

 

Soccerdad, cross-fertilization doesn't usually affect the fruit, which should be determined by the genes of the tree bearing the fruit. It will only affect the genetics of the seeds and any resulting seedlings.

 

Fruits from two of the trees came down during the recent big wind. I didn't record which fruit came from which tree but the verdict on one of them was "wonderful".

They have been inside for a week and the skin on the uneaten ones is now totally black. Yet when cut open they seem OK. I have yet to look into this, but I will definitely be out there fertilizing them with a tiny paint brush next year.

One flowered earlier than the other two; can I take some of its pollen and keep it in a jar until the others are ready to be fertilized?

 

I've eaten fruit from local trees also. There used to be one in Seattle that was quite large. The 2006 edition of Trees of Seattle by Arthur Lee Jacobson mentions an additional example 28' tall, plus another 24' tall - and locations of 5 other plantings. We also know the species is able to grow in the region because Burnt Ridge Nursery in Onalaska grows and sells the plants.

 

I don't really have room for such tall trees, and anyway I wouldn't be able to get at the fruits, but I can see how they could get very very tall. I will have to top them this winter, much as I hate to do so.

 

28' is a small tree, of course, as far as it goes - if you can't accommodate, say, a 15-20' tree maybe you should be limiting yourself to shrubs.

 

Al Chomica, a friend of mine here in Nanoose Bay, has been very successful growing Paw Paws. Here is an email from him he has given me permission to share.

Paw Paws are not difficult at all. They are just different from other plants. The Sunflower variety that I propagate is self-fertile and I have proven it over the last few years. The flowers come out as males and morph into females and that confuses a lot of people too but the tree doesn't find any problems with that.

This year I got 80 fruits from one tree that was pollinated by flies that I attracted in a bucket with a festering pork liver. I hand pollinated the six flowers from my Mango variety when they finally turned female. I took pollen from the Sunflower male flowers that had just opened up. The Mango has a far superior fruit with a strong strawberry aftertaste and is quite heavenly.

My experimental planting is doing well but is definitely out of sync with the season as the seeds are still sprouting. These seeds were stratified last November until March when they were planted deep in a long pot. They didn't start to sprout until July and they grow, oh-so-slowly at first. They come out as little stumps without leaves and are a perfect target for pill bugs that just chomp their terminal ends, usually killing them, but not always. I had to grow them in a moat during this period.

I brought them in the house where they are now under lights and they are doing very, very well but I don't want to be babying them like this so I have to develop a new sprouting strategy based on the amount of time required to get them to grow. So, following the advice of my mentor in Australia, I am running tests with wood vinegar in various concentrations and time to see if I can simulate what the seed requires in nature - which would be travelling through a digestive system before being deposited in a fertile mix that overwinters on or in the ground. That shouldn't be too tough...

I won't stratify the seeds but will soak them and plant them now in the hopes they sprout early and can be planted out in the spring or early summer. I have 30 plants growing that had 39 people wanting them last fall but they were too small to sell. This year I literally have hundreds of seeds from a self-fertile fruit tree that I am learning to propagate.

 

I grow Paw Paws in Nanoose Bay on Vancouver Island and may be able to answer any questions the folks on this forum have. I just had a fruit tasting and sold my last tree off from 2016. Paw Paws are not difficult to grow, they are just difficult to understand because they are not like any other tree...

 

Well, a 33' x 120' lot in Vancouver ( 50' x 120' lots are no longer really available) currently costs over $3,000,000 U.S. so one is rather constrained. And my biggest Paw Paw is under the lines that bring the current into my house... So I'll top them. I should be able to do so without making them look really ugly.

 

Down here the trend is to fill nearly the whole lot with architecture, and it is not always limited to heavily urbanized neighborhoods. With some of it being rows of single family houses being replaced by mixed use developments (condos upstairs, shops downstairs) where one building may be an entire block in length.

 

Just noticed this post. I'm new to Nanoose Bay and happy to hear PawPaws will grow happily here. I'll have to get a few trees in the spring.

I grew up in Southern Ontario where PawPaws are native, but never knew what I was looking for and have never tried the fruit. Al, if you have a bumper crop next year I will gladly buy some fruits off you :)