What flowers are on your list? I got my seeds for the allotment garden this year two weeks ago, but ended up just going with vegetables.
I’ve got a list of nurseries that carries North American native seeds that I got from a visiting professor so let me know and I will dump it on you. Wikipedia tells me it’s called a ”community garden” in North America, it’s basically a plot of land that has been subdivided into smaller plots for individuals to grow their own food for a small fee. It’s great if you live in a small apartment but still wish to do some gardening. The city provides water and a spot to dump garden refuse but everything else you might need like seeds etc you have to buy yourself, or barter from your neighbours. I got some strawberry seedlings last year in exchange for a wheelbarrow of horse manure from my Italian neighbour (I also got to borrow the wheelbarrow from him).