I posted this on the poppies cubit,but I'll do it here also.
I am going to seed the white variety of poppy rhoeas (Shirley type poppies).
In the fall I want to collect the seed of these.
I am going to also seed a coloured mix in another part of the yard.
At what distance must the varieties be separated so no cross pollination occurs?

Good question...unfortunately I don't have a clue. I have planted the basic shirley poppies and find that over time the typical mix will revert to red .

I don't know either, but pretty far I think. Remember, those bees can can fly in pollen from your neighbors yards, too. If you really can't live without one certain type of flower, it's probably safer to buy new commercial seeds. Sometimes it's fun, though, to harvest your own seeds and see what you get as a result.

Karen

Yes, I am thinking it is not worth trying to keep poppies isolated in a city environment.
If I were serious about it I would make a net enclosure and seed a pot of them inside.

I've had pretty good luck with Poppy seedlings coming mostly true. I find the occasional odd one, but the majority are what I hoped for. If its only to re-supply yourself with seed each year, its worth a try.

I will save the seeds and just see what they give next year.