- You Will Get 1500 Seeds Of Snow In Summer (Chickweed) Cerastium Biebersteinii Flower Seeds. - Description: - Name: Snow In Summer. - Other Common Names: Chickweed. - Scientific Name: Cerastium Biebersteinii. - Color: White. - Plant Seeds: Outdoors After Frost / Indoors Weeks Before Last Frost. - Plant Height: 6 - 12". - Plant Spacing: 12 - 18". - Bloom Time: Spring. - Hardiness Zone: 3 – 7. - Light Requirements: Sun - Part Shade. - Soil & Water Preferences: Average.