When to plant Michaelmas Daisy?

Michaelmas daisies thrive in full sun or partial shade, though flowering is most prolific in a bright, open position. They tolerate a range of soils but perform best in moisture-retentive loam or clay that doesn't dry out completely in summer. Avoid very light, sandy soils unless you're prepared to water regularly. Plant container-grown asters in spring (March to May) or autumn (September to October). Spring planting gives them a full season to establish before their first flowering, while autumn planting works well if the soil isn't waterlogged. Dig over the planting area and incorporate a bucketful of well-rotted compost or manure per square metre to improve soil structure and moisture retention, especially if your soil is on the lighter side. Space plants 45 cm apart to allow for their mature spread and to ensure good air circulation, which helps reduce mildew problems later. Dig a hole slightly wider than the root ball and plant at the same depth the aster was growing in its pot—burying the crown too deeply can lead to rot. Firm the soil gently around the roots to eliminate air pockets. Water thoroughly after planting, even if the soil feels damp, to settle the roots in. Apply a 5 cm layer of organic mulch such as garden compost or bark chips around the base, keeping it a few centimetres clear of the stems. This conserves moisture and suppresses weeds while the plant establishes. In dry spells during the first growing season, water weekly until the roots have spread into the surrounding soil.