Common name: ‘Radio’ pot marigold
Botanical name: Calendula officinalis ‘Radio’
Virtues: Blooms all summer. Great in containers or in the ground.
Flowers: Vivid flowers have dense, pointed petals around a sunny yellow eye. The orange petals resemble a pen’s quill.
Habit: Hardy annual, 18–24 inches tall with a compact shape.
Season: Summer in cool climates, fall or spring in hot climates.
Origin: Cultivar first introduced in the 1930s.
Cultivation: Grow in full sun in the North, part shade in hottest areas of the South. Tolerates poor soil but requires good drainage. In the North, sow seed outdoors in early spring or indoors 4 to 6 weeks before the last frost and transplant seedlings out when they are 4 weeks old. In the South, sow seed in late summer or early fall for bloom the next spring. Plants will self-sow in good conditions.
Mail-order sources: Baker Creek Heirloom Seeds, Planet Natural, Seeds & More, Select Seeds (coming 2011)
Starting from seed? Check out Clarington Forge’s planting dibber, a great tool for planting seeds or transplanting seedlings.
Get a great deal on four flower-gardening CDs.
Read about familiar and less common annuals, plus seed-starting and transplanting techniques, in Horticulture’s Annuals CD.