I’ve got 15 or so ripe looking hips on my Snowdwarf, pollen was from Jens Munk, Robin Hood, and R. Moschata (the repeat bloomer from Vintage). Some are beginning to look a little shriveled, none are soft yet, but all are bright tomato red. Stems are still green. This batch was pollinated early - most no later than middle April.
How much longer should I wait?
Once picked, should I give the seeds a cold cycle before attempting germination, and if so how long?
Any experience out there?
I cannot give you any special germination advice. However, I can relate my experience with Schneezwerg open pollinated seedlings.
For me they have been very weak growers. I do not know exactly how many seedlings I had but it was probably at least 20 or so. They have all died. The last one struggled since 1997, but died this past winter.
I kept them on their own roots so it is possible that they would have been nice plants if budded to a rootstock.
You schould gather these hips as soon as completely red or some animal will eat them. Let the hips dry now and sort the seeds later. Give them the standard two monthes cold wet cycle before sowing.
May be your seedlings were selfpollinated. I raised a few Schneezwerg progenies with mixed results. Some plants rather strong, tall and open growing as S. I was looking for more fertility and did find it… from its pollen on a rugosa seedling.