All Good Things Organic Seeds Burdock Root Seeds (~50): Certified Organic, Non-GMO, Heirloom, Open Pollinated Seeds from the United States Packet: ~50 seeds (0.45 gram) - Certified organic by Oregon Tilth: OT-017423. Non-GMO, Heirloom Variety 90 days to immature root. 180 days to mature root. Biennial. Plant in Early Spring through Mid-Summer. Located in Ojai, California, United States. Plant Good Seed. Know the Source