MH first couple of weeks of flowering

[Alistair]

Supposedly, using a metal halide for the first two weeks of 12/12 can help eliminate the "stretch" during the initial stages of flowering. I was thinking of trying that and switching to an HPS for the remainder of the grow. Are there any drawbacks to starting off with a metal halide?

Thanks. Ali

 

[ozzydiodude]

IMo I dont think ther e would be people have grown and a few swear by MH for the full grow.

 

[legalize_freedom]

Yeah ...I have read of some people that use MH all the way through also. I've never heard that theory though...thats interesting where did you hear/read this AY? I'd be interested in the how's, and why's? if you could direct me to a source?

 

[Alistair]

I must have read that on this site. In fact, I read that not too long ago. It might have been hearsay, but I probably got that here.

I do believe that HPS, in and of itself, encourages stretching, so, not using it in order to help eliminate stretch during flowering makes sense too

I don't know. If I read it here, then maybe, someone will be able to give us some input . I probably let my plants veg a bit too much, and now my closet will be over-crowed. As most people do, I plant more than I need in order to anticipate the male plants to be tossed. I've been known to toss females too. Oh well, we'll see.

I should borrow a camera again; these look really nice this time, and I'd like to post a pic or two.

 

[BBFan]

Hey Ali!

I usually keep them on MH right at the flip and I don't experience too much stretch. But I've never done a side by side to see if there's a major difference.

What I can say is that the red spectrum of light is very important to flowering.

It could very well be that keeping the mh in there for the first few weeks slows the onset of flowering- if so though, the time delay has been insignificant relative to the end result and how compact the buds end up.

Go borrow that camera and give us a peek!

 

[zem]

IMO this theory could very well be true since it does make sense, in the first days of flowering the plants are usually not forming flowers but stretching their stems so maybe that the red light is most important when the buds start forming, ive never read it before but it does make sense, you learn something new every day

 

[pcduck]

Some people have been doing that for awhile now.Supposedly reduces the stretch.

I have seen no time delay, in flowering when using a mH over a hps.

I think Growdude does his whole grow with mH

 

[nouvellechef]

I used mixed light on last grow. Not sure if it helped stretch or not but the barely gained in height. I think as long as they are not stretching for the light and you have a good amount of lumens, don't think it would make that big of a impact. Not to mention HPS just has more lumens. I could of been really stoned everytime I went in the garden, but it seemed since I use vertical bare bulbs, the MH was alot hotter than the HPS .

 

[PencilHead]

Alistair, I've been contemplating this for a couple of days now. Even tried to think who I could PM for some feedback.

Leaving the MH bulbs seems like it would indeed slow stretch, but then, does bud formation begin as quick under the MH spec? When would be the optimum time to go to HPS? Too many questions.

I went 12/12 last night and went ahead and changed bulbs to HPS anyway. I'm doing several things different this grow and want to have some sort of prior knowledge to draw on.

I'm really interested in what everyone has to say on this--great thread.

 

[legalize_freedom]

Thanks for the reply AY, and others. I have read some stuff on the mixed light in flowering. When I hung my 400w light in my grow with my 600w I had thought I might run it on MH (it's a switchable ballast) but I decided to just go ahead and run it on HPS. By the time I put the 400 in there plants had already been flowering a couple of weeks anyway. Maybe after this grow is done, I will try it with the clones. Interesting theory, and it does sort of make sense.

 

[umbra]

I must have read that on this site. In fact, I read that not too long ago. It might have been hearsay, but I probably got that here.

I do believe that HPS, in and of itself, encourages stretching, so, not using it in order to help eliminate stretch during flowering makes sense too

I don't know. If I read it here, then maybe, someone will be able to give us some input . I probably let my plants veg a bit too much, and now my closet will be over-crowed. As most people do, I plant more than I need in order to anticipate the male plants to be tossed. I've been known to toss females too. Oh well, we'll see.

I should borrow a camera again; these look really nice this time, and I'd like to post a pic or two.

I first read it in an article written by Ed Rosenthal, many, many years ago.

 

[Alistair]

Thanks, I'll think it over. I certainly won't use the MH for the whole grow, because it doesn't have near as many lumens as the HPS.

 

[ishnish]

I too have met people that choose MH the whole way through.
and I've heard about keeping MH just for the first weeks of flowering to reduce stretch... couldn't say where or when i heard it..
I might have resources to experiment in the near future, i'm sure others are already on it though..

 

[Droopy Dog]

Consider how it is in nature.

When plants first start to go into flower, say late July, the sun is still high to the north and plenty of blue light. It really doesn't start to change much till the equinox (Sept 21), and goes below the equator. Then the angle is noticeable and you get that red tint to the light.

In SoFla, when I still lived there,that red tint didn't become really apparent till close to the solstice (Dec 21).

DD

 

[ishnish]

Consider how it is in nature.

When plants first start to go into flower, say late July, the sun is still high to the north and plenty of blue light. It really doesn't start to change much till the equinox (Sept 21), and goes below the equator. Then the angle is noticeable and you get that red tint to the light.

In SoFla, when I still lived there,that red tint didn't become really apparent till close to the solstice (Dec 21).

DD

Good logic there I'd say.

 

[Alistair]

Yes, good logic.