GDP, short for Granddaddy Purple, is the deep purple indica that Ken Estes introduced in Oakland in 2003. Estes launched it at his club on Telegraph Avenue, and Leafly now calls it a famous indica.
Estes did not build GDP from a seed pack. He traces it to an old Northern California plant called Purple Medicine, kept by the Pomo people long before it reached a dispensary shelf.
Purple Medicine and the Pomo connection
In a 2026 Leafly interview, Estes said Purple Medicine was not grown commercially because it yielded only about a pound per light. In Skunk magazine's Breeder Diaries, he described receiving it from a Blackfoot friend who got it from the Pomo tribe's medicine man.
Estes told Skunk it was an 18-year-old variety used in ceremonies. The flower was dark as midnight and reminded him of Thai stick from the 1970s. LA Weekly reported that the Pomo gave him the cut so he could run it himself, and that it became the plant known today as Granddaddy Purple.
How a club name became a household name
Estes told Leafly the name came to him the moment he saw the plant. His first thought was that it looked like the grandpa of all weed, and he corrected himself to Granddaddy.
The dark buds confused customers at first. Estes told Skunk that people asked what was wrong with it, so he offered a money-back guarantee. Not one person brought anything back. GDP later appeared on the TV series Weeds and became a favorite of rappers such as Snoop Dogg.
Estes was no newcomer. LA Weekly reports that he opened his first dispensary in Concord in 1997 and estimates he opened about 20 clubs over the years. He also survived federal raids in 2005, 2008 and 2009 and a federal case that ran for six years.
A purple plant built for big harvests
Leafly lists GDP as an indica with a flowering time of about 60 days indoors, or 7–9 weeks, and high yields. The flowers bloom in shades of deep purple under a snow-like dusting of white resin.
A 2019 Califari profile noted that Ken Estes GDP was available as clones through Dark Heart Nursery. According to LA Weekly, Estes later had GDP tissue cultured to clean it and preserve it, and two growers were running the clean version by 2023.
Leafly's database records other lineage accounts, including Mendo Purps, Skunk and Afghan, and Purple Urkle × Big Bud. Estes' own account is the Purple Medicine story.
Candyland, Cherry Pie and the GDP family tree
Estes kept breeding from his plant. He built Ken's GDP by backcrossing, which LA Weekly describes as essentially Granddaddy Purple Bx1. He then crossed the male with seven other strains, and he says plenty of people won cups with those seeds.
He told Skunk he is proudest of Candyland, which carries GDP traits while pushing yield higher. He has since backcrossed a Candyland male into his Candyland stock and crossed it with other strains for limited releases.
Leafly lists Cherry Pie and Purple Punch among GDP's descendants. Cherry Pie, a GDP × F1 Durb cross, went on to parent Cherry Fritter, the Fresh Baked staple. Summit Boys turns that same cross into Cherry Fritter badder. Cherry Pie also sits behind Forbidden Fruit, its cross with Tangie.