MH or HPS for AF Plants???

Hi All....Just started germinating some Blue Himalaya Diesel seeds. This will be my first grow using Autoflowering seeds. I've got a 400W ballast with both a MH and HPS bulb. Was curious what someone with experience recommends using. I've heard stories of people using a MH bulb for the first 3 weeks or so then switching to HPS, and i've also heard of people using HPS from the get go to harvest. What do you all think? Also was gonna have these girls under 18 hours of light straight through.

Thanks for the info...

HPS all the way through if you can keep temps low enough. More lumens = more growth.

I agree, the only lights i use for every cycle is hps, and I have 2 mh ballasts just sittin there. HPS RULES.........................

to be honest, I have grown with MH(never flowered with mh) and i've grown with hps, To be honest, i think you get more yeild with hps throughout the whole thing. Though mh might be slightly better for veg grown, Wehenver i used mh for veg it only seemed to make the plants have less nodes per area and it made the plant Not stretch, But stretch more than it would with hps. I've always had my own opinion, and i always go hps all the way ^_^, buds seem more dense and to be honest, i get more yeild with hps all the way ^_^

I just cropped 5 autoflowers, they will grow anyway you do it. I ran under T-5's for about 3 or 4 weeks then switched to HPS, either way you will get bud, its a matter of how much. I would start under MH if you have a light available and once you see the buds start switch to HPS, they need both spectrums, I ran them on 24 hrs the first 3 weeks, then switched to 20 hrs another 3 weeks then down to 12 hrs the last 3+ weeks with the last week being a flush. And like bighomey says, based on the hours and spectrum they will stretch or stay shorter, they grow in height during the darkness

I've found that the plant more effeciently absorbs light from Metal Halides during veg, and this higher effeciency is what counters the higher lumens/lower absortion rates offered by HPS lights. Personally, my plants were noticably greener under MH, but I would have to agree with the bunch that overall HPS is the best bulb to use throughout, and obviously the one & only for flower phase. I have seen some combo lights with a 600w HPS & 400w MH under the same hood & wired to the same ballast, which I thought was a cool idea if you want both spectrums at both times. But those are a bit pricey.

Mazar i Shariff said:

I've found that the plant more effeciently absorbs light from Metal Halides during veg, and this higher effeciency is what counters the higher lumens/lower absortion rates offered by HPS lights. Personally, my plants were noticably greener under MH, but I would have to agree with the bunch that overall HPS is the best bulb to use throughout, and obviously the one & only for flower phase. I have seen some combo lights with a 600w HPS & 400w MH under the same hood & wired to the same ballast, which I thought was a cool idea if you want both spectrums at both times. But those are a bit pricey.

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BULLSHIT>>>>THE PLANTS LOOK GREENER UNDER MH BECAUSE OF THE COLOR OF the light...its in your mind, i thought that too until i put my HPS GROWN PLANTS UNDER a blue spectrum light, And its just the light color man. THE PLANTS LOOK HEALTHIER UNDER A WHITE LIGHT RATHER THAN ORANGE.

everybody i know says hps all the way ^_^

bighomey said:

BULLSHIT>>>>THE PLANTS LOOK GREENER UNDER MH BECAUSE OF THE COLOR OF the light...its in your mind, i thought that too until i put my HPS GROWN PLANTS UNDER a blue spectrum light, And its just the light color man. THE PLANTS LOOK HEALTHIER UNDER A WHITE LIGHT RATHER THAN ORANGE.

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No, that's actually not the case. It's been scientifically proven that the blue spectrum produced by Metal Halides is the preferred kelvin rating for faster vegetative growth, whereas the orange/red spectrum from higher kelvin rating HPS bulbs helps induce larger flowers than what can typically be grown under MH. I'm not being fooled by some optical illusion bro haha

If you are tight on money and don't want to pay for a switchable ballast & extra bulbs, totally understandable, HPS all the way would be the best choice in that situation. But I can say that over multiple cycles of using MH during Veg, moving to HPS when switching to flower phase, it has worked best for me and I have seen great results. Of course, I prefer outdoor so I say screw high electricity bills and harvest the best light source in the world for free, THE SUN! =)

One love!

buying lights tomorrow, 150w HPS and 150w MH, small grow only 3 plants, should i have both lights on throughout the entire cycle, or ....use MH for veg/HPS for flower
cheers dudes!

Im gouing to be growing Blue Himalaya Diesel but under cfl's be good to how u get on m8

im going to be growin 5 x short stuff automatic feminised blue himalaya diesel, 5 x short stuff automatic Snowryder feminised and either 5 of short stuff automatic Mi5 or short stuff automatic ONYX.I will have a minimum total of 1100w of cfl which my me increased to 1280w look forward to watchin how u get on ganja38

GanjaDwarf said:

buying lights tomorrow, 150w HPS and 150w MH, small grow only 3 plants, should i have both lights on throughout the entire cycle, or ....use MH for veg/HPS for flower
cheers dudes!

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Use as much light as you can throughout the cycle! Don't just use one 150w during veg and another 150w during flower. You def want to take advantage of the whole 300w setup. And I've actually experimented with having MH and HPS running all the way through and I the ones that got a good mix of both throughout the large room were def more frosted than the others. Consider this before you purchase tomorrow, ONE 400 WATT HPS light should be CHEAPER and give you better results than 150w MH and 150 HPS. While both spectrums would be great, the difference in lumens that the extra 100w will give you will more than outweight the benefits you will get from the other setup. If you want two lights, go for TWO 250-400 WATT LIGHTS & REALLY REAP THE BENEFITS =)

Mazar i Shariff said:

Use as much light as you can throughout the cycle! Don't just use one 150w during veg and another 150w during flower. You def want to take advantage of the whole 300w setup. And I've actually experimented with having MH and HPS running all the way through and I the ones that got a good mix of both throughout the large room were def more frosted than the others. Consider this before you purchase tomorrow, ONE 400 WATT HPS light should be CHEAPER and give you better results than 150w MH and 150 HPS. While both spectrums would be great, the difference in lumens that the extra 100w will give you will more than outweight the benefits you will get from the other setup. If you want two lights, go for TWO 250-400 WATT LIGHTS & REALLY REAP THE BENEFITS =)

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Thanks for your reply Mazar, man! Yea i understand what u mean! one 400w hps is a good bit cheaper actaully, i thought it would be better for both spectrums as you said, but alot of people i hear using just hps throughout entire cycle and getting results/bud just as good as those using mh and hps, guess i never thought about the extra 100 watts, thats a hell of an increase in lumens actually when you think about it, and I was just about to buy my lights too lol, think il go for a 400w hps now, thanks man, appreciate the time you took to reply, cheers from ireland
y'all be lucky now ya hear
Ganja