I've always found pawpaw floaters to be bad. I only plant the ones that sink, but have often split the floaters to see that they were bad. How long did you let them float before giving up on them? Most will float at first even just after fresh harvest.

Last fall I saved ~50 paw paw seeds. I cleaned them and put them in a
moist paper towel in the fridge as soon as I ate them fruit. Several weeks later I put them all through the float test, almost half of them were floaters,
but saved them anyway, in a separate bag.

In late January, I took 5 floaters and 5 sinkers, put them in ziploc
bags with a wet paper towel. In 1 to 2 months, all 10 seeds
germinated. The first floater germinated a day or two after the first
sinker, the last of each also germinated within a couple days of one
another.

Alex

Interesting!.....I to have been collecting paw paw seed from 3 different groves within a 15 miles radis and all seed have been floaters.....cut into several and they all looked sound(fully developed)....I had already assumed this must be the norm for the species....What gives?

Thanks for the replies --
I contacted a friend of mine up in Ontario who is a seed person and he said the seeds need to soak for a day or so and most all will eventually sink. Mine have been soaking since around noon and several are now sinkers.

Marshall

Yep, I usually only have about one in ten sink within the first couple of minutes. It can take a few hours to start seeing the majority sink. The ones that don't sink within about four of five hours are probably bad.

Hello,
I write from Bulgaria. Is there anywhere in the on-line space where You make an exchange cuttings from plants. I have a few seedlings from seeds asimina triloba and I need cuttings with leaf buds to graft them. Can anyone send me the cuttings from famous American varieties?

Peterstamov:

There are exchange forums here on GardenWeb. You can trade for seeds in the Seed Exchange Forum, and you can trade cuttings and plants in the Plant Exchange Forum. There are also other places such as the Yahoo group called The North American Scion Exchange. Unfortunately, because of GardenWeb's idiotic policy, I can't post a link to that group. It can be found easily by searching Yahoo groups though.

I do see one possibly large obstacle though, sending plants, cuttings, and seeds from one country to another often requires things such as a phytosanitary certificate. Obtaining such things isn't impossible, but it is probably more trouble than most hobbyists would want to go to for pawpaw cuttings. I would suggest that you seek out a plant nursery that could ship to your country.

You might also want to look into obtaining material from the US National Plant Germplasm System. They do primarily provide material for US usage, but can, in many cases, also ship to other countries. I will leave that research up to you, but could help you if you run into a "roadblock".

Thank you very much! Comprehensive!

Another plant the "float test" doesn't work on is Calycanthus floridus, All the seeds floated like corks,but when I planted them about 50% came up.

"Another plant..."

As I said years ago, if done right, the float test has been very reliable for Asimina triloba seeds in my experience. I think a lot of people think they can just pour the seeds in water and see them sink right away. With pawpaw seeds, usually you have close to no sinkers immediately. The seeds have to remain in the water long enough for them to imbibe enough water. Those that don't sink eventually are either hollow or only partially filled with viable material. Pawpaw seeds do not need to be scarified but do need to be cleaned.

Here's how I check viability of Paw Paw seed. As I clean the seed from the fruits I take a pair of pruners and cut a couple of seed in half. If the seed is solid and sound it is good, never heard of floating pp seed.
Sow seed right away, it will come up 100% the following Spring.
{{gwi:452416}}

Yes, but I cut the floaters into and plant the sinkers.