I agree with High_time. I'd transplant when its anywhere between 8" and 12".
Keep in mind it will grow according to the size and shape of your pot.
I have a friend who grows in 2ltr pop bottles. He just cuts the top off and starts down low and as the plant keeps growing upwards he keeps adding soil higher and higher.
But because the roots dont have allot of room to grow, they get root bound quicker and the plant starts to shoot upwards. Where as if you use a bigger widder pot your plants roots will take longer to surround the pot. But it will get bushier and wider. Much like the pot its in. And also, when you're plant is at a young age its an excellent time to start LST and topping.
And as for the wind, as long as its not a drastic change in wind, like if the plant went from indoor to outdoor with strong wind then that would hurt it or stunt it.
However, if the plant has been outside since a young age it will develop strong stems and learn to fend for itself. Also make note that the stronger the winds the more feedings you'll have to give your plants.
