Using MH bulb for last 2 weeks of harvest? What is the science?

ChesusRice

Well-Known Member
I read that using a MH bulb the last 2 weeks of Harvest will increase resin and trichome production. What is the science if any behind that? I understand why Cacti produce mescaline, It is bitter to anything that trys to eat it. But what is the science behind using MH? People have said use it the last 2 weeks and it will promote production. But the last 2 weeks is when the plant is bulking up and producing more trichomes anyways. So how can you tell the difference?
 

Sunbiz1

Well-Known Member
MH bulbs emit UV/UVB radiation when not coated, so yes...they will certainly beef-up a harvest when mixed with an HPS(which emit ZERO UV)...or even a CFL grow using 2700K flowering bulbs.
 

ChesusRice

Well-Known Member

racerboy71

bud bootlegger
i've been using mh's for my entire grow for like the past 3 or so grows after talking to someone on another forum about sunpulse mh's..

the sunpulses come in various k ratings, much in the same way the cfl's do... you just buy the correct k rating for w/e phase of growth you're in at the time.. ie, i use the 6 k for veg, and the 3 k's for flowering.. they even offer a 10k for the last two weeks of flowering, which i have, but have yet to run it yet..
like has been said, mh's have light in the uv range, which is supposed to increase tric production.. it's believed that trics are used by plants kind of like a sun tan lotion... the more exposure to uv lighting, the more tric production on that plant, or that's the science behind it although i'm not 100% about it tbh..
it's also said that the you get a fuller flavor profile from using mh's over hps bulbs.. something about the way mh's effect the terpenoids in cannabis..

overall, like i said, been running the sunpulse mh's for a good three of so grows now, and i have to say i'm impressed.. i'm loving them.. the blue dream i just ran has to be some of the stunkiest bud i have grown to date.. is it all the mh's or do i just kick ass at growing, lol, idk, but what i do know is i'm not going back to hps anytime soon.. it has been said though that hps bulbs will increase your yields while mh's will increase just about everything else, ie, tric production, flavor, etc, etc.. :D
 

racerboy71

bud bootlegger
edit, the reason i started to ask about the sunpulses in the first place was that i was running a digital ballast and was using eye hortilux blue brand bulbs, about $110 or so per..
about a month into a new bulb i went to check on the girls and the bulb had blew.. yeah, i was pissed to say the least.. the sunpulses like a few other brands like digilux and oshio are said to be made in conjunction with the higher frequencies that digital ballasts fire at, extending the life in the process.. :D
 

ChesusRice

Well-Known Member
edit, the reason i started to ask about the sunpulses in the first place was that i was running a digital ballast and was using eye hortilux blue brand bulbs, about $110 or so per..
about a month into a new bulb i went to check on the girls and the bulb had blew.. yeah, i was pissed to say the least.. the sunpulses like a few other brands like digilux and oshio are said to be made in conjunction with the higher frequencies that digital ballasts fire at, extending the life in the process.. :D
Local store guy is pimping the 10k bulbs but says you need a digital ballast for that
 

polyarcturus

Well-Known Member
MH bulbs emit UV/UVB radiation when not coated, so yes...they will certainly beef-up a harvest when mixed with an HPS(which emit ZERO UV)...or even a CFL grow using 2700K flowering bulbs.
face palm.


anyways MH dont emit UVB coated or not, its all in the galss its made from, the coat is for UVA and protection fabrics from fading and sunpulse never got back to me, so i highly doubt they are using the proper glass to emit UVB so all you can count on them for is some UVA and deep blues which can emulate the effects of UVB.

but besides all that using MH last 2 weeks of flower wont hurt, probably would increase thc level a little, but your buds will probably not get larger during that time period tho.(vs using hps) and the frostyness acheived porbably wont be all as impressive as you thought.


@racerboy ask dbkick about the 10k sunpulse he used it the last 2 weeks.... from what ive seen of db i say that was normal frostiness for him and it didnt do much of anything.
 

polyarcturus

Well-Known Member
also racerboy ive switched up to more MH dominant grow too, my results using an MH vs. and HPS the MH has been dominating. although i contaminated my results by adding a 270w hps.
also im just using a regular old hortilux mh 400w on mag ballast. MH has more PAR light than hps and thats the fact of the matter. hps should really only be used for mid and end of flower in my new opinion. IMNO
 

ChesusRice

Well-Known Member
They dont make sunpulses in 10k at 1000 watts
As far as MH I guess if you have good genetics It wouldnt be worth losing weight over a small increase in frostiness. Especially if the leaves look like someone puked sugar all over them anyways
 

Kite High

Well-Known Member
nope not the solution will not provide enough ...here you go as these are the only AFFORDABLE sources for uvb amounts high enough and without too much heat available
http://www.reptileuv.com/megaray-metal-halide-uvb.php
http://www.lightyourreptiles.com/ard3t546in54.html
See i have found with my meter that at least 150 uw/cm2 is the least amount needed to produce ratio manipulation and anything over 400 uw/cm2 reduces yield with no more increase in affect

Also uvb exposure throughout the entire grow sprout to chop same lighting schedule as your main lighting produces the best outcome
 

polyarcturus

Well-Known Member
They dont make sunpulses in 10k at 1000 watts
As far as MH I guess if you have good genetics It wouldnt be worth losing weight over a small increase in frostiness. Especially if the leaves look like someone puked sugar all over them anyways
exactly. kite high pointed you in a good direction if your interested in UVB but there are also reptile flourescents, which are okay, good for small grows, and mercury vapor bulbs for reptiles which are powerful and good for lager grow but have thier pit falls too, but these are the ones i prefer.
 

Kite High

Well-Known Member
i've been using mh's for my entire grow for like the past 3 or so grows after talking to someone on another forum about sunpulse mh's..

the sunpulses come in various k ratings, much in the same way the cfl's do... you just buy the correct k rating for w/e phase of growth you're in at the time.. ie, i use the 6 k for veg, and the 3 k's for flowering.. they even offer a 10k for the last two weeks of flowering, which i have, but have yet to run it yet..
like has been said, mh's have light in the uv range, which is supposed to increase tric production.. it's believed that trics are used by plants kind of like a sun tan lotion... the more exposure to uv lighting, the more tric production on that plant, or that's the science behind it although i'm not 100% about it tbh..
it's also said that the you get a fuller flavor profile from using mh's over hps bulbs.. something about the way mh's effect the terpenoids in cannabis..

overall, like i said, been running the sunpulse mh's for a good three of so grows now, and i have to say i'm impressed.. i'm loving them.. the blue dream i just ran has to be some of the stunkiest bud i have grown to date.. is it all the mh's or do i just kick ass at growing, lol, idk, but what i do know is i'm not going back to hps anytime soon.. it has been said though that hps bulbs will increase your yields while mh's will increase just about everything else, ie, tric production, flavor, etc, etc.. :D
well there are no hid bulbs that emit enough uv to cause effect...it takes a quartz glass formulation to allow uvb through...regular glass as used for the outer envelopes is regular glass and due to hids being manufactured to be around people hey do not allow uvb emmision

now there are some new studies suggesting that the blue wavelengths, 400nm-450nm have some of the same causations as uvb and vice versa but i n the ratio manipulation it is not as effective so that is probably the improvement you are witnessing from the mh
 

Sunbiz1

Well-Known Member
well there are no hid bulbs that emit enough uv to cause effect...it takes a quartz glass formulation to allow uvb through...regular glass as used for the outer envelopes is regular glass and due to hids being manufactured to be around people hey do not allow uvb emmision

now there are some new studies suggesting that the blue wavelengths, 400nm-450nm have some of the same causations as uvb and vice versa but i n the ratio manipulation it is not as effective so that is probably the improvement you are witnessing from the mh

well there are no hid bulbs that emit enough uv to cause effect>>>

>>>LINK?
 

colonuggs

Well-Known Member
thats all i use is mh for the entire grow... for years now

$23 a bulb for 1000s 4000k.. case of 6 for $150....Same bulb at the grow store $85-95

 

Kite High

Well-Known Member
well there are no hid bulbs that emit enough uv to cause effect>>>

>>>LINK?
per my solartech uvb meter...its the glass of the outer envelope that is the wrong formulation for uvb emissions ..has to be that way as hid bulbs available except for the one I listed above are designed for use around people and its a fed regulation law of very little allowed uvb if around people

please excuse my vernacular as I am really very high on dabs...lol
 

Kite High

Well-Known Member
Hehe!, most *grow bulbs are sold without a safety coating. Sorry, I should have mentioned that fact as opposed to assuming people who actually buy them would bother to research.
the safety coating would be to block uva to prevent fabric paint fading etc....but it is the glass formulation that blocks the uvb and uvb is what causes the effect of ratio manipulation we seek
 
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