They both have the same chromosome number [2n=16] (although there are references to a tetraploid version of sylvestris 2n=32); a hybrid between the two may not have fertility problems due to mispairing (at least not due to chromosome number differences).

If you have successfully frozen pollen from other species I would suggest using the same method. If not you could try collecting pollen on a q-tip, making certain it is dry and freezing the q-tip in a container. Whatever method you use you could test it in the autumn by collecting some pollen, freezing it for a few days and trying it with crosses on the japanese anemones.

Thank you for your comments, I shall go ahead and collect the pollen and see what later comes of things!

Terry

did you have any luck yet?

Charlie-ia, I had up and forgotten to attempt to do so ... though, might reconsider it. Rather, I've been focusing on the hybridization of very cold hardy roses.

Terry

thanks for replying. I guess i'll have no excuse for not giving it a go myself then.