Switching HPS to MH in middle of veg?

BeverlyRollins69

BeverlyRollins69

Well-Known Member
Hey all, is it actually bad to switch from HPS to MH lighting in the middle of the veg cycle? Reasons? Here's the situation...

I'm currently running a 1000W HPS 24/0 in a closet grow for my 12 plants (homebred from Hawaiian and Master Kush parents). They are about a month into vegging, ranging from 3"-12" tall, and it's at least 2-3 weeks until they will go into flowering. Problem is, being the summer and all and having a closet grow, the lowest average temp I can keep in there is right at 85 (believe me it's taken all my capabilities just to get it down this far). I figured switching to MH would help beat the summer heat and drop the temp a few degrees but I've seen misc posts saying this is bad, although I haven't seen any reasons why.

Thanks!
 
Doalude

Doalude

Well-Known Member
You can switch but I would put it real high at first to let the plant get use to the new intense light, but MH are still HID lights (high intensity) and they still run hot, if its going to be only for 2-3 weeks I would keep HPS in place because the plant is use to that light and temp by now, 80-85 degrees is still ok, you just don't want temps in the 90's then all you'll have to do is switch to 12/12 for flowering.
 
BeverlyRollins69

BeverlyRollins69

Well-Known Member
^That's my big question...will the plant care (i.e. adverse side effects) if I switch it to MH now, and then switch back to HPS in a few weeks to flower?
 
chosuichi inu

chosuichi inu

Active Member
don't do it........i use hps all the way thru and my temps avg 85 sometimes higher. don't listen to all the environment bs you'll see. its a pot plant, period. they love the heat and humidity. best plants grow naturally outdoors right ???? unless you live in paradise i know its not a constant 70-80 with low humidity. think about where the best weed comes from....hot/humid locales........also if you're gonna veg 2 months with hps you're gonna have monsters. i've personally never gone more than 6 weeks veg under hps, usually less. let em grow......i'll include a pic o my 85-90 baby....just ventilate well and there will be nooooo problem.trust me
 
Doalude

Doalude

Well-Known Member
Just keep what you got going on this grow it will be alright, but on your next grow then start with the MH for vegging then switch to HPS for flowering. Your using and HID light now so thats much better than floros or cfl's......its a learning experience so after a few grows you'll learn what to do.......you have your light so keep your ppm's and Ph inline and you should do really good!!!
 
chosuichi inu

chosuichi inu

Active Member
capncash said:
and vegging under hps makes for stretched out plants. do you know what your talking about?
Click to expand...
hps stretch plants huh......maybe you should do a little homework before you get on here and try to correct someone son. hps stretch....amazing. don't make me post a pic of my stretched hps plant....
 
A

AZGanja

Member
I have seen a few videos out there which talk about how the distance between nodes has been stretched due to the red spectrum of HPS.

Hope this thread continues - anyone who has used
HPS for veg, with previous experience using MH for veg - would be good to hear your thoughts. Did you notice a bushier plant using MH than HPS? That's always been my understanding.
 
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