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Grow Weed So Purple It’s Practically Black

May 19, 2016

If you’ve been puffin’ the ganja long enough, you’ve come across purple buds. KF7, Purple Pineberry, Grape Ape, Mile High Purps – just to name a few. Some of the buds from these strains bear flowers that almost appear black.

Purple Chitral Kush

Purple Chitral Kush

Intensely purple nugs please the eye so much that cannabis connoisseurs quest from dispensary to dispensary in search of these exotic-looking buds purely for the aesthetics of blazing something so beautifully alien. And as any culinary artist will tell you, appearances can affect the overall experience. Ganja enthusiasts often describe deep purple flowers as carrying sweet aromas that pack a bouquet of berries and fruits.
Looks aside, are these flowers really that much different from your typical run-of-the-mill green buds? And more importantly, how can you get your own cannabis to bloom this violet?

Cool Colors, Cool Temperatures
Sprouting nugs that resemble grape popsicles takes some patience and a lot of practice. To do so, simply manipulate the temperature during the 12/12 light cycle. Cool the plant’s surroundings to 10°C (50°F) during the dark phase of the 12/12, and you’re golden (or, in this case, purple).
What’s happening? The green we see in most buds is chlorophyll, the little verdant organelles that collect and process sunlight into energy. When we drop the temperature to 10°C in the 12/12 cycle, we fool the plant into thinking it’s autumn. And just like a maple leaf, your buds will shed their chlorophyll, draining out the green and revealing those deep violets hidden in the buds.
Just be sure you’ve got yourself a strain that’ll turn purple. However, with the right strains, you can get the nugs to near blackness. There’s nothing sweeter than popping out a bottle of lush, black nugs for unsuspecting friends – especially if they’ve never seen anything like it before.

Chemical Key: Anthocyanin
Where does that purple color come from, though? It comes from a class of molecules called anthocyanins, which reflect violet frequencies of visible light. You can find anthocyanins in other plants besides cannabis: eggplants, plums and, of course, violets all contain anthocyanin.

800px-Anthocyanidine

Anthocyanidine Molecule

There’s a ton of health benefits to anthocyanins, too. Like other terpenes, they feature a lot of the same medicinal properties as cannabinoids, such as neuroprotection, anti-inflammation and free radical elimination. (Free radicals are those nasty buggers that cause aging and cancer.)

However, don’t get it twisted. Purple strains may contain more anthocyanin than your average herb, but using the cold-room trick on your plants won’t jack up their anthocyanin levels. Anthocyanin concentrations remain pretty stable, despite how chilly your grow room gets. When you drop the heat, all you’re doing is stripping the chlorophyll, not increasing the anthocyanins. Connoisseurs tend to notice grape flavors attached to bruise-colored cannabis, though anthocyanin has no detectable scent or taste. The “grape-iness” comes from other terpenes.
Regardless, if you happen to pull off a pile of ebony nugs, enjoy your harvest. If you cure your flowers correctly, your milky-white trichomes will really pop against the black petals, which makes for some wicked-looking nougats.

Flowering Marijuana Hemp Plant

Purple Buds Ready to be Harvested

By Randy Robinson

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