Hopefully Lucky_p will come along and see this. I think you need to make sure to choose a site that will get some sun. Moist, rich bottomland soil is ideal and along a river sounds right.

With most trees, I would take the seeds and pot them up as needed in root pruning pots for a year or so but pawpaws are supposed to be difficult to transplant so planting in the final place after the seeds break dormancy might be ideal especially if you can set up some kind of barrier to protect them from browsing critters.

From what I've read, they may benefit from some shade for the first couple of years then as esh_ga said plenty of sun. If they get all the water they need from the river, then they may do better in full sun from the get go.

I will look in my Dirr manual when I get home and let you know if I come across anything noteworthy.

I think I'd start the seeds in containers and grow them on for a couple years until they get some size - they grow slowly the first couple years has been my experience. I sowed seeds in a 16 inch deep nursery tub with drainage. Seed take about 50-60 days to germinate and warmer the temp the better. Seed sown in a cool environment took a lot longer to germinate. Two years gets some nice roots on the plant at which time I'd remove them from the tub and transplant them in the ground.
My 2�
Marshall

I've grown many pawpaws from seed. I've started many in pots and started some in-ground to start with. My preference, IF I have access to the site where they will be grown to start with AND I can provide sufficient protection and followup care for a few years after they are planted, is to grow them from seed at their permanent location. Doing so allows the tree's root system to be best adapted to the site. This is not to say that a transplanted tree won't do fine, but growing in place is the ideal. It also saves work by eliminating the need to transplant and to fix any root problems caused by being pot-grown.

As j0nd03 indicated, pawpaws do appreciate partial shade for their first couple of years. Pawpaws will produce more fruit if grown in full sun after this initial period. When I grow seeds at the site to start with, I usually use 50% shadecloth covers fitted around small cages I use to protect the trees from predation. I remove the shade cloth in the fall following their second year.

One side note I'll add is that pawpaw seeds usually don't sprout top growth until kind of late in the season. Don't give up on your seeds when you don't see them sprout above ground level in the spring. It's important to monitor and provide sufficient soil moisture even though you don't yet see you trees.

Greenthumbzdude's case may require something different than what I'd normally do for a few reasons. First, the site may not be a full-sun location. That's fine because pawpaws typically grow as an understory tree in nature, BUT they won't provide optimal fruit production if they are grown in partial shade. Next, the trees may need to be grown in containers for a while for a variety of reasons (access and care, protection from humans, protection from being damaged by debris etc if the area occasionally floods, etc). If the seeds are being grown in containers, I recommend fairly deep containers (within reason) with wire mesh on the bottom (air-prune the root system). Using care when transplanting and correcting root issues will result in a higher success rate. I've found that if the seedlings have been grown correctly (especially with air-pruned roots) and planted correctly, the transplant success rate can be very very good. Another factor, I should have probably already have mentioned, is that they should be transplanted in spring (not fall or winter as most trees tolerate, or even appreciate, in warmer climates).

One advantage of starting them in pots is that you can effectively get two seasons of growth the first year, because you can start them early, and extend the season at the end as well. As Brandon mentioned, seeds planted in the ground won't show top growth until late in the season, often July or even August. Started indoors, you can get top growth much earlier, like April.

Hopefully, you have kept them moist and cold. If they have dried out, they are probably dead. After 90 to 100 days of cold treatment, put them in a warm place and you should start seeing germination in a couple weeks, although some may take a couple months. I put mine in plastic ziplocs with a moist paper towel, and plant them as soon as I see the root emerge.

I vote for 1 year in a container, here's why: I started a batch in the Spring of 2010 in 3 liter soda bottles. In the spring of 2011 I transplanted several of them into the ground just as the buds were swelling, and left several in their containers. At this point, a few roots were visible through the container for most of the plants. The ones I transplanted grew much more than the ones that remained in the pots. The container plants set their terminal buds much earlier. In other words, the plants in the ground continued to grow later into the season, and some of them are over 3 feet tall now. Concurrently, I planted some seeds in the ground in the spring of 2010, and they all look like runty little things compared to those I started in pots. My soil is heavy orange clay, so YMMV depending on your soil conditions.

Rabbits will bite off little pawpaws, so I'd put a cage around them.

Alex

I've grown a bunch in containers and have had good survival rates when I finally got around to outplanting them - in full sun, with no shade/protection. Yeah, I know the 'experts' say they need it; I just didn't have the time to fool with it.
I'm sure deep pots would be great, but I've just straightened out - or pruned off circling roots, plunked 'em in the hole and never looked back. Even had some that spent 2 years or more in 20 oz styro cups that did just fine when I outplanted them.

Have never direct-seeded, but I'm going to be doing that along the creek here on the farm this year, in areas where there are not currently any growing; seed from the KYSU plantings.
Will the direct-seeded plants make it? I dunno. But I don't have the inclination to care for and transplant a bunch of pawpaws.

{{gwi:327251}}
Here's what works for me:
I collect seed from nearby road in park after traffic has run over fruit, usually early October. Within a day I direct sow seed in bottomless tree bands. I overwinter in unheated prop house. The following mid to late May seed starts to pop up. Germination is 100%. Growth will be commensurate to the care the seedlings receive.
It's worth noting how incredibly adaptable Pawpaw is. It grows near me in incredibly hostile, xeric, serpentine soils in full sun, it continues down the hill right up to the muddy banks of the Susquehanna river growing happily in shade. If you go there in Summer you can't miss the numerous Zebra Swallowtails which require Pawpaw foliage. I've never known deer to eat foliage of Pawpaw.

Sam, I've seen articles discussing the deer overpopulation problem in areas of the Northeast, describing that the only green thing below the highly-visible browse line is pawpaws.

Rabbits (Grrr!) will snip off young pawpaws during winter, but they'll grow back with abandon the next year.
Buck deer LOVE to rub isolated pawpaw shoots when the rut is approaching.