Step-by-Step Growing Guide
Calendula (Calendula officinalis) thrives in cool weather and tolerates light frost — it is one of the few annual flowers that can be sown in fall in mild climates for late winter and spring bloom. It prefers well-drained, moderately fertile soil with a pH of 5.5–7.0; rich soil produces more foliage and fewer flowers. Direct sow seeds 1/4 inch deep in the garden 2 weeks before last frost in spring, or in late summer for fall bloom. Thin to 12–18 inches apart. Calendula dislikes transplanting due to a sensitive taproot — always direct sow or use biodegradable pots. Water moderately, about 1 inch per week; reduce watering as summer heats up, as calendula declines rapidly in heat and humidity. Deadhead spent flowers every few days — the plants produce an impressive amount of resinous sap on the stems and spent heads that needs to be cleaned from hands and tools. In cool-summer regions, calendula blooms all season; in hot climates, it blooms spring and fall only with a summer gap.
