If they don't germinate this spring, you might need to start over with new seeds. In Z5 you should still get enough cold to do the job in the soil. If you get more seed this summer plant them in the soil this fall. That has worked well for me.

My experience with stone fruit seeds is that a dry seed is a dead seed. Your best bet is to either eat the fruit then plant right away, or eat the fruit then place them in your fridge in a baggie with slightly moist peat moss or potting soil when they have had enough chill they will start growing in your fridge so you should check them every few days after about 3 months in the fridge.I usually put seeds up around mid September and by Christmas the apricots start then shortly after plums and peaches. The germination rate is very high using the quick plant or quick fridge method where I have had zero germination with dried seeds after only having them dried a few weeks on my counter.And never allow them to freeze hard as that will kill them as well. I experimented one year and put about 40 to 50 plum, cherry,and peach in several large above ground planters. It was a very cold winter and went down to -20F with no snow cover....in the spring none of them germinated but several that were planted in the soil next to the planters still came up even though there was no snow on the ground.

Glenn

This is helpful information. I found a plum tree in my area while walking the dogs. The plums are yellow, the size of a sweet cherry, and the seeds are the size of cherry seeds. They are juicy and plum flavor. So I picked up a bunch of fruits. They are over ripe now. I washed them and planted in potting soil. I suppose they should go in the fridge now. It seems a little early, being only mid August.

2 years ago I planted wild cherry seeds, in flower pots and just kept them in the yard through the Winter. That Spring they grew nicely, very fast. Unfortunately we had a summer dry spell and my watering person did not water them so they died.

I also have a self-planted peach under a genetic dwarf peach tree. I think I will pot that up too. I can't take credit for sprouting it though - it is a volunteer.

The little yellow plumbs your talking about are Japanese plumbs (Loquats) and it can take 5 yrs to fruit under good conditions. Do not let the seeds dry. If you can't plant immediately keep moist in wet paper towels, just like lemon tree seeds.I know this is an old post but thought I should reply to benefit others with questions