Use of black lights

Hey all, i'm new here so please be patient. I've seen on other forums but was unable to locate a similiar thread here. I was curious as to what effect black lights may have on a grow? I was told awhile back that it would change the color of the flowers. I would appreciate any answers that any experienced growers may have.
Peace..

as far as im aware the spectrum of a dark light bulb does absolutely nothing to a cannabis plant in terms of growth

i think you are referring to a bulb that generates some UV light, there are some mixed opinions on this
some claim that increased UVB(i think that is the spectrum) can increase certain cannabinoids, it is supposed to more closely mimic the spectrum seen at the tropics or high altitudes
supposedly more helpful with strains that were bred for those environments

as far as im aware with some deeper research black lights are completely pointless m8

there are two variables that will allow or cause change of color of the plant and or the plants buds.

1. During the last two weeks of flowering.. expose the plant to cool temps.

2. Genetics of the plant being grown.

There are no other ways of adding color to a plant.. period.

There are no color additives.. no special words... no majical dances.. nothing. Those are the only two things that will cause color changes of a plant.


peace..

Here are a couple of links that I've found useful in my quest to increase potency:
Pot Potency
Wiki's take on ultraviolet
Chemical Ecology of Cannabis

There are three spectrums of UV - UVA, UVB, UVC.
UVB is what we want. Blacklights produce mainly UVA which have no effect in stimulating THC production. A popular option is using reptile lights - Reptisun 10.0 UVB. Coral/Reef lights and tanning lights are also used.

Reptisun 10.0 put out on average 40-50 microwatts2 at about 12-18 inches form the bulbs surface... The mega rays provide much more around 150-225 microwatts and these throw the uvb much further at about 1-3 ft from the bulb.. For reference on a sunny day on the east coast usa uvb reads at about 300-375 microwatts2

Click to expand...

Here's a compilation of useful graphs of various reptile UVB bulbs:
http://www.uvguide.co.uk/phototherapyphosphor-tests.htm#totalUVB

I switched out my HPS to MH in my last weeks of flower, but I noticed a sharp decrease in the nutes that were used. The HPS is going back in but with a dedicated UVB lamp. I'll have pics in my journal.

Thanks for all the info.