"Granddaddy Purple (aka Grand Daddy Purps) is one of the most popular Indica strains on the west coast and is perhaps the most well known 'purple' cannabis strain in the US.
Created back in 2003 by Ken Estes in the San Francisco Bay Area, Ken and his team sought out to create the ultimate Indica hybrid by merging two strains with fantastic genetics - Purple Urkle and Big Bud. The product of these two, Grand Daddy Purple, is a spitting image of it's parents' two best qualities - the deep and dark purple hue from Purple Urkle and the overgrown, dense buds of Big Bud. The dark purple buds blend well with the bright orange hairs and frosted white trichomes that generously cover the bud making it an extremely photogenic strain.
From San Francisco down to Los Angeles, Granddaddy Purple is one of the most sought after Indica strains due to it's Hollywood looks and classic Indica effects. Despite this popularity, however, many growers and those working in the dispensary world have claimed that Grand Daddy Purps is almost identical to another famous purple strain - Grape Ape.
Some even go so far as to speculate that these two strains may be in fact the same. Others simply say that they are so eerily similar in lineage, look, taste, and effects that they are simply confused with one another by growers, dispensaries, and consumers alike.
Perfect for night time use Grand Daddy Purple hits both the body and mind initially but quickly fades into a smooth body buzz like most heavy Indicas do. For patients Granddaddy Purps is ideal for pain management. It can also be effective at treating insomnia, depression and anxiety. Novice users beware though, this strain can pack a powerful punch. We'd recommend starting with a hit or two and waiting a few minutes before opting to consume more
Granddaddy Purple grows best indoors but can be grown outside as well. Flowering commences usually around 70-77 days when grown indoors and growers can expect harvest in early October when grown outdoors. The oversized buds may begin to weigh down the plant, especially if grown outdoors. When grown indoors the plant should be short and stocky enough to hold the weight but you may want to prepare to offer some support around the 60 day mark if you notice the buds beginning to wear down the plant's frame. Yields can top 4 ounces per plant on an indoor grow and well over 3 pounds per plant on an outdoor grow. For optimal results keep temperatures within the 70's throughout the grow cycle and keep humidity between 50-55%."
quoted from https://www.wikileaf.com/strain/grand-daddy-purple/