Starting pawpaw seeds

Starting the slow crawl towards spring here in PA by starting my pawpaw seeds. I’m trying a new method this year that I hope works OK.

I’ve taken various plastic containers with lids, filled them with potting soil and planted the seeds about 1" deep. The containers went into the utility closet, which is pretty warm this time of year with the furnace running. They should germinate in several weeks to a month, but no shoots for 2-3 months. Seeds have been in the fridge stratifying since Sept or Oct, depending on the source.

I’m hoping to get more growing season this way, last year my few seeds that the rodents didn’t get didn’t emerge until August and grew 3-4" tall. My main potential concern with this is the taproot, but I’ll cross that bridge when I get there.

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I had good success two years ago getting pawpaw going. I stratified them in the fridge over the winter in a bag with a damp paper towel. I pulled the whole bag out about this time of year and simply put it in a warmer spot. I recall that it took them between three and six weeks to germinate. I just kept checking the baggie and when I found any sprouted seeds, I planted them in a “Tall-One” tree-pot that I had ordered from Stuewe & Sons online. Those pots are 4" x 14" tall, and they handle the taproot nicely. Then I left the tree pots in bins in the basement until they just emerged from the potting mix. By then it was May or June, so I was able to get them outside right away without having to worry about hardening off and they had a full growing season. Most grew between 8" and 12" the first year.

Two years later, they are still quite small. What slow-growing trees they are! I put three in the ground that first fall, 2014. One died over winter and the other two are my largest so far. The rest I stored in three ways, still potted over the winter. I buried most in mulched leaves. I put some in my unheated garage, and I brought some into my cold-room. The ones in the leaf mulch survived fine. The garaged ones all died but one. The cold-room plants did great, and I brought them out early into the warm part of the basement, so they were already leafed out by last frost.

I planted a few more in the ground the following spring, 2015, when I finally had their beds ready. They did not grow much. The rest I left in the tree-pots for another season, and most of them did okay. I’ll have to plant them out, pot them up or sell/give some away this spring, assuming that they come through the winter fine again.

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I planted my paw-paw seeds in Deepots - from Stuewe. They’re 2.5" wide, and come in depths of 3,5,7,10, or 14" deep. I’ve got some in 14", some in 10", and some in 5". The deeper pots are more vigorous. I know from removing the dirt from one that died that the taproot goes straight down until it gets air-pruned.

BTW - if you use 14" pots - plan on going directly into the ground. There are very few pots tall enough to up-put to from a 14" pot. Mainly TreePots - 6"x16" or 8"x18"

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I’ll be potting them up into MT49 pots.

they transplant poorly, BUT you may want to consider starting seeds in a pot where you can baby-sit them, overwintering Year 1 in a garage or cellar, then transplanting still-dormant seedlings in March…it seems dormant plants don’t have as much an issue w/ transplant shock as growing paw paws…plus Year 1 the taproot will still be like 12-15 inches

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I have read that they should not be transplanted when fully dormant, and that they do better when transplanted in the spring, when they are just starting to show some growth. I have planted out eight Pawpaws, three in the fall, and five in the spring. One of the fall-planted trees did not make it, but all of the spring planted ones survived the first year. Now I have to wait until May to see how they have done this winter.

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I second Paully’s idea. Neal Peterson, pawpaw breeder, told me to wait to transplant pawpaws in Spring until there’s an inch of new growth AND transplant them into warm soil. So I laid black plastic over the soil where I eventually planted them to let sun warm it up. Got all takes.

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interesting, I can’t hardly argue w/ Neal…

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I started my pawpaw project last winter. I got seed from Cliff England and some from KSU. I’ve been told they are photosensitive when they are young and full sun can kill them since they are an understory tree. However they are supposed to be more fruitful when mature if in full sun.

My solution was to grow them in containers for the first two years so I could control light exposure. Of course tap root issue (circling and j-hooking) in normal smooth sided containers, so I needed to deal with that. I ended up using a root pruning container system. I started them in Rootmaker 18 express trays under lights. This air prunes the tap rot quickly causing upstream branching. After about 12-16 weeks I transplanted them to 1 gal Rootbuilder 2 containers and kept them on my lower deck which only gets a couple hours of direct early morning sun followed by a few hours of filtered sun and then shade all afternoon. They grew pretty well the first growing season. I’m sure I posted pics on some thread on this site.

They have spent the winter in my cold room. As soon as I see any indication of green up when I put them out this spring, I’ll transplant them to the 3 gal Rootbuilder 2 containers for this summer. When they go dormant next fall, I’ll plant them in the field in full sun.

KSU has a lot of good information on how to speed up germination after stratification and how to speed growth. I ended up using heating pads to warm the mix to about 90 degrees which clearly promoted growth.

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Forest- I like your pawpaw project. Would you consider an experiment: field planting some of your seedlings in Spring 2017 (after they start pushing growth) rather than Fall 2016, then compare survival percentage? I have never had good luck with fall planting pawpaws, although some of these failures were due to bareroot plants- never again!. I read that pawpaw roots go entirely dormant in winter, unlike say apple roots that continue to grow when above freezing. Not sure if this plays a role in fall planting problems. Would love to see results of such an experiment.

Sure, but this may not be a fair comparison for most folks. Folks transplanting bare root trees are pretty much forced to do it when they are dormant. They experience a year of sleep, then creep, before they finally leap in year three. This Is largely due to transplant shock with the bare root trees. Rootmaker grown trees are a bit different. As long as you can provide supplemental water as needed, they can be transplanted in the dead of summer with no issues. This happens because the container has a very dense root ball with lots of branching and countless root tips. I cut a couple cable ties and the container completely unwraps leaving the root ball completely intact. So, there is virtually no transplant shock to the root system. There is no need to wait for root buds to form before the plant begins growing.

My constraint will be time available. I’ll try to plant some in the spring of 2017 as well and compare. I just want to make clear that the results may not be representative for non-root pruning approaches. If the fall planting issues have had to do with the root system, I should not have them. If they had more to do with the tops having problems with the first winter, then I should have results similar to you since we have a similar climate.

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Great. I also lost a good portion of fall planted pot grown pawpaw several years in a row. By far my best success is with pot grown, spring planting. From my own experience and reading some other reports there also appears to be a big survival difference between seedlings vs grafted pawpaw, the latter having higher mortality even with proper shade for a couple years. Everything about pawpaws is unusual/strange but makes it a challenge.

Hello folks new here.
I started pawpaws three years ago and they just don’t seem to get in a hurry growing. They are now about three feet tall. At this rate I don’t know if I will live long enough to harvest fruit;)
Is this slow growth normal?

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Sounds fairly normal. Are they in part shade or full sun? Do you fertilize?

They’re faster growing than Feijoas - I have one year old “trees” that are 6" tall.

It’ll take off soon, I bet. You should see fruit in a few years.

So I started my pawpaws in soda bottles last year, and it looks like I do indeed have the dreaded j-hook/circling to deal with. Any recommendations on what I should do about that?

Cut them off. It will set back the tree, but if you plant them that way, the likelihood of constriction and poor development in later life is high. If it is not too bad, sometimes you can straighten them at planting time but it really depends on the situation.

This will give you the equivalent of a bare root tree. This is the way most trees are sold. They are grown in a bed and then the roots are pruned by the shovel when they are extracted. The energy used to grow the removed roots is wasted, and they will suffer transplant shock. Presuming they survive the transplant shock, they will grow.

When you use an air pruning container system, the tap root get pruned at the tip when it hits the air causing upstream branching. Then the second and tertiary roots are pruned at the tip when they hit the air. Since there is no open wound, there is less chance for disease to enter. Also, there is no energy wasted in growing roots that will later be cut off. Instead, that energy goes into developing more dense roots in the container and faster top growth.

Good Luck!

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I’ve posted this picture before, but I’ll add it to this thread. I started these trees under lights last winter. The large tree in the foreground of the picture is of one of the larger pawpaws from the first batch planted last winter. The smaller trees in the back ground in the roottrapper bags were started in a later batch last winter. The picture was taken July 21st last summer.

The tree in the foreground is in a 1 gal Rootbuiler II container. When it greens-up this spring, I’ll transplant it into a 3 gal RB2 for this growing season. I’ll try to take some more pics then.

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Wild pawpaw are understory plants their entire life not just when they are small. Tame pawpaw can be planted outside of those conditions. Pawpaw love water, leaf mold and the fungi present in those conditions. You can grow them outside those condition but I would match their natural habitat as close as possible. They don’t like wind either. Tame papaw are not something I grow though they are much less finicky about conditions. I’ve got ones growing in as close to their natural conditions as possible and they are growing quickly.I know I’ve mentioned it before there are upland and lowland wild pawpaws. The upland you can grow in sunlight but they produce walnut sized or a little bigger papaw whereas lowland pawpaw need the better conditions and produce 6-8 inch fruit. Tame pawpaw are likely crosses of the two naturally selected for better adaptability and larger fruit and then grafted to wild rootstock.

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Actually, pawpaw start out as understory plants - but their secret hope is that the canopy above them disappears in a few years. They start out very sensitive to UV light, but by their second birthday… they can handle it. Pawpaw will grow better and produce more once acclimated to full sunlight.

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