- Name: Cosmidium Brunette - Other Common Names: Burridges Greenthread - Scientific Name: Cosmidium Burridgeanum - Color: Yellow With Mahogany Centers - Plant Seeds: Outdoors After Frost / Indoors Weeks Before Last Frost - Bloom Time: All Summer - Hardiness Zone: N/A - Plant Height: 18 - 24” - Plant Spacing: 15 - 18” - Light Requirements: Sun - Soil & Water Preferences: Average - Quantity: 30 Seeds - Other: Cosmidium Is A Texas Native That Has A Wonderful Chocolate Scent! These Beautiful Flowers Are Very Easy To Grow And Are Similar To Cosmos & Coreopsis But More Hardy & Tolerant.