Question I’m just starting outgrowing what I want to know is how young can I place my seedlings under the lights, I use hps lights 250w and 600w. I use the 250 at the start of the seedling stage for the first two weeks and then it goes under the 600 but what I want to know is how young can I place the seedlings under the 250 watt light and how close should I have it?
You can put them under the right away. Put the light at 24-36 inches up. Make sure you put them in a humidity dome. Keep the grow media just damp and spray the top of the dome (inside) a few times a day to keep humidity up.
I agree, whenever you want pretty much. Just adjust height as necessary.