This image was created by Rick Thompson and is available for purchase in a variety of sizes through IStock.
This fully mature and ready for harvest marijuana flower is tinged purple in color. It is loaded with triichomes, the small sparkles coating the plant surface. These glands contain the THC and other chemicals that give marijuana its potency. The purple color is due in part to genetics and in part to good gardening techniques. Expert cannabis gardeners induce the purple color by maintaining colder temperatures in the grow room near harvest time.
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