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Difference with MH & HPS when growing AFs?

Kaneh

Member
Have you guys done any experimentation using different light spectres with AF strains.

I mean, if you flower with 20/4, why don't you go all the way and also use MHs?:chin:

Has anybody tried this?

...or is it just :crazy:?
 

Troy.No

Member
Correct me if im wrong, but i think MH the first 3 weeks is bether than a HPS. AF's are usally in veg only 21 days or so before they enter bloom.
 

spacely

New member
they will flower under any light schedule. . . but they are still flowering. . . so with the lights, treat them like any other strain in veg for the first three weeks, then like any other strain in flower for the next five to seven weeks. which means use your mh or 6400 k cfls for the first three weeks, then switch over to the hps or 2700 k cfls for the remaining flowering period (although with cfls its not a bad idea to keep a couple 6400 k bulbs around during flower).
 

S_a_H

Autoflower Crusader
ICMag Donor
Veteran
I would agree here and use a MH for the first few weeks at least and if you have the room I continue to use it along with a HPS when flowering.

S_a_H
 

*mr.mike*

Member
Not my own results, but others have gotten really awesome, very dense growth with MHs, but mold and mildew were a problem (without chemicals).

Think broccoli, but bud.

Then think about mold living inside there.

The HPS is awesome, just not as dense, and a week later.
 

Kaneh

Member
they will flower under any light schedule. . . but they are still flowering. . . so with the lights, treat them like any other strain in veg for the first three weeks, then like any other strain in flower for the next five to seven weeks. which means use your mh or 6400 k cfls for the first three weeks, then switch over to the hps or 2700 k cfls for the remaining flowering period (although with cfls its not a bad idea to keep a couple 6400 k bulbs around during flower).

I agree with you guys, but has anyone actually done side by side test with MH and HPS during flowering?
 

Rosy Cheeks

dancin' cheek to cheek
Veteran
I occasionally run both Metal Halides and HPS' in flower.

Results vary from strain to strain, but in general, metal halides will grow a more compact plant (than HPS), the plants will need more time to finish (not a lot), yield will be smaller but the nugs will be harder. The high will be different, less punchy, more trippy.
 

Kaneh

Member
I occasionally run both Metal Halides and HPS' in flower.

Results vary from strain to strain, but in general, metal halides will grow a more compact plant (than HPS), the plants will need more time to finish (not a lot), yield will be smaller but the nugs will be harder. The high will be different, less punchy, more trippy.

That's interesting.
So basicly it could be that with using MH you could get samekind of effect than when harvesting early > more THC high, less bodystone...

I don't know if this is in anyway meaningfull info in real life situation.
Just a question that popped my mind when thinking about growing AFs indoor. So far I have been growing them only outdoors.
But I was planning to do some breeding indoors also, just to get more generations/year.
 

IndianHay

Member
I dont have AF strains but the question is similar...I have both MH and HPS bulbs. Is that right that when i switch to 12/12 i change bulb to HPS right away?
 

Rosy Cheeks

dancin' cheek to cheek
Veteran
Is that right that when i switch to 12/12 i change bulb to HPS right away?

Plants respond differently to different wavelengths of light.

Red light makes plant grow faster (and therefore more spindly), it also stimulates fruit and flower production during flower.

Blue light grows a more compact plant, fruit and flower production will be somewhat held back during flower.

A mix between the two is the best, because it gives a broader light spectrum closer to that of the Sun.

If you're running plants that tend to stretch in flower, and your grow-op isn't adapted to it, it could be a good thing to keep your babes under MH in the first two weeks of flower. That will keep the plants down, and once the budding really sets it, you switch to HPS light.
 
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