Vibrant and long-flowering, these half-hardy, bushy, free-branching plants are a valuable addition to the summer flower garden for providing late interest. Their large, daisy-like blooms are unbeatable as cut flowers and make eye-catching summer and autumn bedding plants with their rich colours. Flower shapes vary due to modern varieties, however whether resembling pom-poms, incurved peonies or feathery doubles, they all appear in profusion. Flowers can reach up to 15cm(6in) across and are loved by butterflies, bees and other pollinating insects.
How to Sow and Grow Asters
Asters do best in full sun, protected from strong winds and in rich, fertile, neutral to alkaline, moist but well-drained soil. Plants are rather shallow-rooted, so will benefit from a mulch of organic matter. Remove deadheads to prolong the flowering season. Tall varieties and those with large heads need staking.
Sow indoors, for surest results, 0.5cm(1/4in) deep, in trays of compost. Keep in a warm position, a temperature of 15-20°C(60-68°F) is ideal. Water well and keep moist. Seedlings usually appear in 14-21 days and once germinated move to a cooler, light position. Once seedlings are large enough to handle. Harden off before planting outside.
Sow outdoors for ease. Where they are to flower, 0.5cm(1/4in) deep, directly into finely prepared soil which has already been watered. Thin seedlings to 30cm(1ft) apart. Water well until plants are established.