Metal Hylide for last 2 weeks?

I've read that if you use Mh bulbs the last 2 weeks of flower, you get tighter nugs. Is there any truth to this?
Has anyone done this?
I was wondering because, I have a switchable ballast and a Mh bulb.
I'm getting close to 6 weeks in flower so any feed back would be helpful.
Don't know weather to try this or not, I can't see it really hurting them. My 1st grow was done totally under a 400 Mh, the buds weren't that big but were nice and tight.

i heard of this too. im gonna try it my next grow. if you do try it let me know your results please.

I'll let ya know if I do. Still unsure though

I've never done it, but I have read that a MH will give you 15% less yield than an HPS but slightly more potent buds...If I were you I'd kind of compromise the time by using the HPS until the buds have stopped getting much bigger then switch to MH...maybe last 1- 1.5 weeks?

that is a fact jack

it be gouwd for da stretch to mon mh instead dem hps reduce dem stretch in da beginnin of flower

so it is good in first few weeks and last few

what i do is run a 250w hps and a 250mh at same time in a 39 inc sq tent i give each pot a 1/4 spin every day and we switch position under lights every week jus like they say for best results with cfl you must mix the lights

you feel me

i also use a uvb

may the grow gods smile on your beans

one love

Hey thanks fellas, I'm gonna play it safe I think, use Mh for the last week of flower, just to see

Yeah I don't know about the weight bud I hear the UV from the MH increases potency and some people recommend using it for the last few weeks and also what RichD said about the stretching.

Yea, sounds good, I'm gonna try it, I wish I could do a comparison to see the diff

ya my buddy said his friend flowers with an HPS then uses a MH bulb for the last week or two of flowering n the buds change to crazy pinks and other trippy colors n im sure it helps with potency.

i just vegged and began flowerr with my 2 girls n ima go grab a new hps bulb to flower for week 2~7 and then MH for week 7&8. results soon to come

Adding Mh to Primary HPS system yes...not switching from Hps to Mh

If I am growing a strain that is prone to stretching, I will use MH along with HPS for the first 2 or 3 weeks of flowering. But I have never used MH on the tail end of flowering. I cant see that it would hurt anything.

Thanks for all the comments, keep 'em comming

metal halide lamps produce more UVB light than HPS lamps.
the higher UVB content causes the plant to increase its resin gland production, as the resin is a natural sunblock....
potency has more to do with genetics however. if you have a low potency strain and flower it under MH, you will get some of the frostiest buds you've ever seen, very sparkly with all the resin production, but they will still be 'not that potent' buds, than if you had some killer genetics flowered the same way.
i prefer to flower under MH and CMH, its a matter of preference for me, i just think a MH lamp produces a better tasting bud in the long run vs. HPS, tho there is no doubt that HPS lamps will produce heavier tighter yields than your average MH.

cool thanks man for the info, I got a good strain, and I'm not too worried about the potency, it's a Orange Mass, veg'd for 2 months and now starting 6th week of flowering since sex was shown on Saterday. I'm gonna try it on the 8th week, not sure if it'll be done in 8 might take 9 which I'm thinking.....

I am using a 400watt HPS hortilux for flowering with 8 CFL's. 5 CFl's are 55000k and 3 27000k, I Vegged mine with a 400 watt HM seems to be doing a very nice job for me. Just giving the idea to try both what can that hurt lol

I only enough room for 1 light and the 2 ballasts would be WAY to hot for my grow area. I'd love to have a 400 Mh and Hps going at the same time, would be some killer huge buds

if you have a pulse start ballast, (a pulse start MH ballast is pretty much the same as a HPS ballast, has 3 components, ignitor, capacitor, ballast core. a probe start MH ballast has 2 parts, capacitor and ballast core...) you can get a dual arc mh/hps combination lamp.... there pretty badass..... expensive though.

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I'm not really sure on the ballast, I think so, it's a switchable ballast. How much is that bulb?

Sups...ops now I spilled some beer, brb. Ok back! Well, a full spectrum is the best so if you have 2 x ballast run 1 w HPS and one w MH. I got this crazy idea I'm gonna try to pull off I bought a used ceiling fan 5$, motor working smoothly and very low noise. I'm gonna cut off all "arms" in half and on 2 of them I'm gonna mount sockets for the bulbs. 1 for MH and 1 for HPS A spinning grow light w full spectrum I know I can pull this off, I just need a ballast for MH and a bulb and ima start a DIY spinning grow light. IAmStoned are very welcome w input to that thread later on, as I know I'll be needing some guidance!

"Blessed is he who, in the name of charity and good will, shepherds the weak through the valley of darkness. For he is truly his brother's keeper and the finder of lost children. And I will strike down upon thee with great vengeance and furious anger those who attempt to poison and destroy my brothers. And you will know I am the Lord when I lay my vengeance upon you."

//peace, CaL

LOL, that sounds pretty cool man, can't wait to see it