# hps vs mh for flowering



## Rambler (Nov 18, 2008)

ok so im planning my next grow and i plan to use cfls for the mother and her clones in veg, and then hps or mh for my flowering box, which will be 4x4 and 6 to 7 foot in height, and what i was wondering was... 

would a 400w hps be better than a 600w in that space? 
reason for asking is iv heard that high wattage hps's can cause fluffy bud and that may lead to the bud being not so "high" in quality which is important to me.

and do hps bulbs from the blue spectrum produce similer results to mh bulbs?

and which in your own opinion (and why) works best?

and thanks for your advice, its much appreciated


----------



## bombbudpuffa (Nov 18, 2008)

If i'm not mistaken, you need 800w for that space(30-50w per square ft). Definitely go with the HPS foe flowering.





> iv heard that high wattage hps's can cause fluffy bud and that may lead to the bud being not so "high" in quality which is important to me.


Not true. I flower with HPS and I get tight buds that are killer.


----------



## tesla (Nov 18, 2008)

Rambler IMO hps bulb work the best in flowering. I would say a 600watts at least. From what I have read by very credible people is that Hps is best for flowering because of the uv spectrum. MH is good for veg growth. Now the fluffy bud not so "high" in quality, I been smoking erb grown under hps and it's very high quality. So many other factors determine how your smoke turns out.


----------



## gettinggray1964 (Nov 18, 2008)

rambler, i have a grow tent that is 4x4x6.5, i started growing with cfls, made good bud, 5 months ago got 400 watt hps, the difference in bud is clear,cfls are fine for veg. but it takes quite a few for that size grow area..... MH is good for veg... are let me say it has the right spectrum of light for veg. and HPS HAS RIGHT SPECTRUM FOR FLOWER...400 watt hps is fine for that area,600 watt better but but will increase temps alot.....


----------



## Rambler (Nov 18, 2008)

thanks guys thats good to hear, il probably go with the 600w as il have a shelf with 9 cut outs for the pots to sit in and an adjustable roof, all painted white.
i thought that maybe the change from cfls to hps might stress them out a little, what do ya think?


----------



## andy52 (Nov 18, 2008)

go for it,the plants will love ya for it.just be careful about the heat.make sure you have proper ventilation.also use the hand test to get the reflector close to the canopy.i run my HPS right on top of my ladies,but i have over adequate venting on my reflector.i can lay my hand on the glass and not even war.especially now that its winter.i have my temps at 65 degrees and sometimes i have to unzip the front of my tent to let the temps rise a little.i love the cold weather growing period.so much easier to keep her cool.good luck


----------



## The Hemp Goddess (Nov 18, 2008)

Rambler said:
			
		

> ok so im planning my next grow and i plan to use cfls for the mother and her clones in veg, and then hps or mh for my flowering box, which will be 4x4 and 6 to 7 foot in height, and what i was wondering was...
> 
> would a 400w hps be better than a 600w in that space?
> reason for asking is iv heard that high wattage hps's can cause fluffy bud and that may lead to the bud being not so "high" in quality which is important to me.
> ...



There is NO debate, HPS for flowering.  HPS produce a red light conducive to flowering.  The blue light of a MH is conducive to vegetative growth.

I don't know where you could have possibley heard that hight wattage HPS cause air low quality buds --nothing could be further from the truth.  Although the airiness/quality of bud is very strain related, you will get the best you can get with higher wattage HPS for flowering.

You would probably benefit by reading the stickies on the different types of lighting.

You need to plan for ventilation now.


----------



## thief (Nov 18, 2008)

when it comes to light i feel that sum is good more is better an too much is just abt right. dont skimp on it.


----------



## la9 (Nov 18, 2008)

I just like to put the option out there that you can modify an HPS magnetic ballast to except MH bulbs for a couple of dollars. If you cut down on your crop or buy 2 400 watt setups, it might be a better option. Most of us are going to digital nowadays so it is a tossup.

Definitely MH is better for Veg and HPS is better for flowering, it is because they are in two different color temperature ranges and the plants use one range to grow and the other one to bloom.

If you had to choose between one or the other then you can get away with HPS for Veg.

As far as stressing them out from switching from CFL to HPS, depends on the wattage difference. I'd definitely keep the HPS as far away as I could and gradually lower the light towards the plant to prevent it from getting burned.


----------

