Artichoke Seeds - Imperial Star80 120 days. Hybrid, Perennial seeds. This predominantly male Artichoke hybrid is noted for its productivity, producing large, uniform, tender green Artichoke spears, sometimes with purple tips. This variety produces more artichokes than most other varieties, and it is easy to harvest, making it excellent for beginning gardeners. Plants are hardy, disease resistant, and heat tolerant as long as they are watered often enough. Each bud grows to be