I use MH from seedlings to 2 weeks into flowering then HPS from then to end. MY reasons for using MH for first 2 weeks of flowering is to counteract the pre-flowering stretch (which is an issue for me with limited headroom). It was worked a charm and have almost halved the amount of stretch.

But.. bottom line... DONT use HPS yet and expect some stretching when you do.
Bluefunk Reviewed by Bluefunk on . Can you switch from MH to HPS Can you do this without affecting it im very sure you can there 1 month and 1 week old and i just switched from MH to HPS let me know you all please. Rating: 5