That's a tough one. I'd start them inside and get them fairly strong before setting them out. I've also read that you can put a fan on them to build up there strength before setting them out. A think I posted a link on wind and container plants. Hope it worked out.

Here is a link that might be useful: Wind and containers

I posted a reply earlier but for some reason it didn't show up. Anyway, I live in Colingwood and I am a bit more protected than you are. I love the idea of the bamboo screening fence though. It sounds like it would be lovely! Is it blowing the actual containers over? I started hollyhock seedlings in paper cups last year which I tightly packed into a frame. Then I moved them into the ground. Now that they are in the garden I can't forget the importance of staking and tomato cages around here. I even stake my callas or they'll blow over.