When to switch from MH to HPS

[mr samsung]

How many weeks into flower should it be before I switch from 600w MH to 600wHPS?

[mickrick]

i usually swap ma bulbs around 7 to 10 days on 12/12 i find there's not as much stretch when using MH for the first 10 days...

[mr samsung]

Cheers mate, I usually use HPS all the way through so I wasn't quite sure when to switch them! Thank for clearing that up for me

[bobjob4u]

If possiable run both lights. For some reason i have found mixing hps and mh makes for better growing conditions. Example,I will flowering under 400 hps, along with at least 100-250watt mh. Guess i do this cause my granpappy taught to grow this way.Kinda just a tradition. But to answer your question i add hps when i see pre-flowering.

[Faultline]

My flower room has HPS lights and is timed for 12-12. So my plants get HPS from the beginning of 12-12 to harvest.