Acclimating D.Metel to solar light.

Good morning every one.

I have a few datura metel under a 250 CFL lamp . As I feel they are tall enough, I want to bring them out. But I really fear the sunburn.

It's the first time I do this (first indoor then outdoor) and don't really know how to process. I was thinking to let them out 1 hour per day, for 2 or 3 days, then 2 hours, and so on....

My garden if oriented full south, protected from the wind, and the weather currently full sun all day long, temperature reaching 27°C.

Thank you for your help !