- You Will Get 40 Seeds Of Crimson Bottlebrush Callistemon Citrinus Flowering Shrub Small Tree Seeds. - Description: - Name: Crimson Bottlebrush. - Scientific Name: Callistemon Citrinus. - Color: Red With Evergreen Leaves. - Plant Seeds: Outdoors After Frost / Indoors Weeks Before Last Frost / Fall. - Plant Height: 15 Foot Shrub. - Plant Spacing: 8 - 10 Feet. - Bloom Time: Mid Summer. - Hardiness Zone: 8 – 11. - Light Requirements: Sun. - Soil & Water Preferences: Average – Dry.