This member of the carrot family has tough, blue-green, spiny leaves, with smooth, rigid stems. It  bears thistle-like flower heads, made up of small greenish-white (turns bluish with maturity) globes mingled with pointed bracts. Prospers in well-drained soil types. Mature plants can be divided in late spring or early fall. It can be an aggressive self-seeder. Drought tolerant. Has deep tap roots so transplants poorly.
 
Collect seed in fall when the seed heads have turned brown. Tap the seed out, air-dry, and cold-moist stratify with the chaff in sand, in sealed, refrigerated containers for two months, or direct sow seeds in spring.