- You Will Get 300 Seeds Of Palmers Penstemon (Beardtongue / Balloon Flower) Penstemon Palmeri Flower Seeds. - Description: - Name: Palmer's Penstemon. - Other Common Names: Balloon Flower. - Scientific Name: Penstemon Palmeri. - Color: Light Pink With Stripes. - Plant Seeds: Outdoors After Frost / Indoors Weeks Before Last Frost. - Plant Height: 24 - 36". - Plant Spacing: 15 - 18". - Bloom Time: Spring. - Hardiness Zone: 4 – 9. - Light Requirements: Sun. - Soil & Water Preferences: Average – Dry.