- You Will Get 20 Seeds Of California Bluebell (Wild Canterbury Blue Bell) Phacelia Campanularia Flower Seeds. - Description: - Name: California Bluebell. - Other Common Names: Wild Canterbury Bells / Desert Blue Bell. - Scientific Name: Phacelia Campanularia. - Color: Blue. - Plant Seeds: Outdoors After Frost / Indoors Weeks Before Last Frost. - Plant Height: 6 - 18". - Plant Spacing: 12 - 15". - Bloom Time: All Summer. - Hardiness Zone: 7 – 10. - Light Requirements: Sun. - Soil & Water Preferences: Average – Dry.