How thoroughly do "they" test out hardiness on new plants?
I sort of offhandedly said this on my thread about Geranium 'Ann Folkard'. The more I think of it, the more curious I am about it. I'm sure someone out there has the answer...
I'm interested to know how the process goes "behind the scenes". How much do "they" really test out and analyze the hardiness (and other factors of course) of a new plant? Do they do it in many locations besides their own? Do they do it over a length of time, or one winter before rushing it out onto the market (sort of seems like they rush it for some of them nowadays doesn't it?!)? Or do they even skip this if they figure the parents involved are hardy, so should the offspring be too? What is the criteria for this process?
I've read of individuals in the buisness and smaller nurseries/companies sending their plant in development to fellow plantsmen/nurserymen (etc) they know to trial and report their findings and thoughts. Is it the same with professional hybridizers and large companies? Do they perhaps send samples of the plants to various trial gardens around the states (or wherever...) for evaluation?
Very interested to learn how the hardiness zone is decided for individual plants. Thanks!