VTMi'kmaq
Well-Known Member
I am just starting to really appreciate this statement! I used to throw all sorts of pics of these great moments but suffice to say I impress who I care to impress.
UVA/UVB the real deal. A must read topic for all growers.
- Thread starter GreenVet
- Start date
Rrog
Well-Known Member
I think Phaeton (hope I'm right) documented a reduction in yield with heavy UV-b.
UV-b has sufficient energy to break down DNA and RNA, and yes you can absolutely shine more UV on a plant than it would get from the sun.
I wish there were better hard data on this, but my current thought (today) is that the benefits of UV-b are real. Too much can be bad. A lot isn't required to do what we want.
I also start the UV during early veg. I read an article where THC precursors were thought to develop during veg triggered by UV. Who knows, but simple enough to throw some UV on them.
I also back off the UV the last couple weeks of flower. Trying to signal the end of the grow, and all that.
Again, just my opinion.
UV-b has sufficient energy to break down DNA and RNA, and yes you can absolutely shine more UV on a plant than it would get from the sun.
I wish there were better hard data on this, but my current thought (today) is that the benefits of UV-b are real. Too much can be bad. A lot isn't required to do what we want.
I also start the UV during early veg. I read an article where THC precursors were thought to develop during veg triggered by UV. Who knows, but simple enough to throw some UV on them.
I also back off the UV the last couple weeks of flower. Trying to signal the end of the grow, and all that.
Again, just my opinion.
Sunbiz1
Well-Known Member
Read the same article, now I'm figuring out how to hang one in the veg room...which could actually use the added heat.
Makes sense to use during veg as well, since June is our max UV intensity month in northern hemisphere...my in-grounds outdoors grow more mass in June than any other month.
Sunbiz1
Well-Known Member
Using it for Malawi gold seedlings, have had the beans for 2 years but was afraid to try a land race equatorial strain(from the mountains no less)without at least some attempt at duplicating lighting.
Sunbiz1
Well-Known Member
After 2 weeks I have noticed a very interesting result. These bulbs are really strong...so only using for an hour or so.
The effects are what I saw outdoors, on my in-grounds 2 months ago. Pistils are reacting the same as they do under natural sunlight, by turning rust colored earlier than I would normally see indoors. I shall be very cautious proceeding with the remainder of experiment, as I do not wish for THC to begin degrading too early.
jfart
Well-Known Member
hey bud, thats a great looking first grow. did you have your light on all 12/12 or just a few hours? did you use uvb until harvest?Put in two 10. Desert Reptile UVB 26w bulbs in 33 days into flowering on my 1st grow. 1st grow yeah, but Ive seen my fair share of fire and Im pretty certain those lights were the cause of it.
Scope some
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Sunbiz1
Well-Known Member
Sorry, should have edited previous posting. The Malawi I have not started with yet on supplemental UV. I have 2 mature bubba kush and a white widow in 5 gals mid-flower that are being utilized currently. The kush are clones cut last summer from my outdoor grow, which makes it easy to compare what is taking place.
Lights have been 160W spots set at 12-18" ht., and I'll try and take some comparison pics next time I pull ladies out for watering. This is the best shot I can dig up of the bubba pistils outdoors last Sept.
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Sunbiz1
Well-Known Member
2 weeks after flipping, but would have begun sooner had I ordered bulbs earlier. On a side note, these 3 plants were vegged outdoors until I had to bring them in b/c natural daylight was getting too short...so didn't want babies flowering.
Www.reptileuv.com has what seems to be a pretty bad ass uvb light called mega ray. Its made to work from 3ft up to 8 ft away and tells you the amount of uvb it puts off at different feet away so it would be good to mount on ceiling. If you go to website its tells alot of good info etc. I was looking into uvb lights when I found this site
Are you asking if I have? Yep Mega Ray. I use a simple metal lamp used for chicken coops. Clamp that bastard where it needs to go.
Pepe le skunk
Well-Known Member
Keep in mind the max UVB in the northern hemisphere in June is flawed thinking because the tropics experience UVB all year and that is the region many of the strains originate. Surprisingly Afghan and that area also recieve good UVB because of altitude. Don't think it would hurt in Veg growth but might not be necessary. When trichcomes are building in flower is where the benefit of UVB is most effective according to today's science. However more study for a veg UVB exposure might be needed to see if it effects a buildup of "THC precursors thought to develop during veg triggered by UV". If you have the article please post the link.
Hope that helps.
Rrog
Well-Known Member
I'd be interested in any links to "today's science" also. That's not sarcasm. I'd really be interested.
This thread had a very comprehensive back and forth and many studies were referenced. http://forum.grasscity.com/indoor-medical-marijuana-growing/336317-uvb-lights.html/page-10
This thread had a very comprehensive back and forth and many studies were referenced. http://forum.grasscity.com/indoor-medical-marijuana-growing/336317-uvb-lights.html/page-10