I planted some a few times, many years ago. I don't remember the bloom time, sorry, but the snails got them every time. So you might want to investigate how you could control snails around them. I don't use chemicals or pesticides so I haven't even tried them lately.

I've had gerber daisies in the ground in New Orleans for years. They bloomed during the snowfall we had a few Decembers ago! They do very well in the ground, but like Louisianagal said, snails can be a problem. I don't use chemicals or pesticides at all. The decollate snail will eat other garden snails so if you see it around, DON'T kill it! Usually after a rainstorm, I'll go out and collect snails to dispose of them or I set beer traps for them. My gerbers have been blooming sporadically lately. They seem to be happy in full sun, are happy to be watered every other day (on a drip auto-watering system) and also seem to be happy beside irises, pincushions & dahlia.

Here is a link that might be useful: Decollate Snail eats garden snails