- You Will Get 25 Seeds Of Cardoon Cynara Cardunculus Artichoke Thistle Perennial Edible Vegetable Seeds. - Description: - Name: Cardoon. - Other Common Names: Artichoke Thistle. - Scientific Name: Cynara Cardunculus. - Color: Purple Flowers / Green - Purple Globes. - Plant Seeds: Outdoors After Danger Of Frost / Indoors Weeks Before Last Frost. - Plant Height: Plants Typically To 4', Flower Spikes To 6 - 8' - Plant Spacing: 3'. - Hardiness Zone: Perennial In Zones (5) 7 - 10 (Also Grown As An Annual In Cooler Climates). - Bloom Time: Aug - Sept In Cooler Northern Climates. - Harvest: Typically Sept - Oct, Depending On Climate - Generally 120 - 150 Days. - Light Requirements: Sun. - Soil & Water Preferences: Average.