How to plant asters
Also known as Michaelmas daisies, asters are fantastic clump-forming perennial plants loved by pollinating insects bearing wonderful daisy-like flowers. Bringing much needed colour to the garden in late summer and early autumn, they look especially beautiful mixed together or interlaced with lime green foliage plants such as euphorbias, hostas and ferns. They make great cut flowers.
Plant in well-cultivated, fertile soil in sun or partial shade. Cut back and mulch in late autumn, and divide clumps every few years to maintain vigour and flower quality.
Asters are supplied in 9 cm pots. Always unpack and plant on arrival.
Potential problems, pests and diseases:
- Aphids: these sap-eating insects can weaken plants and spread viruses. Whenever possible, pick off by hand using gloves.
- Eelworms: these microscopic pests navigate through plant tissues and feed on the content of their cells. Leaves turn yellow, distort and die back prematurely whilst growth may be stunted. Watch out for any signs of infestation and destroy any affected plant at first sight. Dispose of any deceased plant material and debris ahead of the growing season to prevent any risks of infestation.
- Snails and slugs: these pests enjoy munching on young shoots, stems, leaves and flowers. Watch out for damage!
- Botrytis/grey mould: this fungal disease usually caused by excessive moisture, warm temperatures and poor air circulation can initially be seen as brown spots/grey mould on the leaves and stems. If you spot any signs of this disease, immediately remove affected bulbs/plants and destroy. Botrytis is an airborne virus and can spread rapidly in the breeze so do not compost infected material.
- Fusarium wilts: this soil-borne fungal disease causes plants to wilt abruptly. Leaves begin to yellow and shed, fungal growth start spreading on stems, and roots may rot. Destroy any infected bulbs at first sight and replace contaminated soil. Dispose of any deceased plant material and debris ahead of the growing season to prevent any risks of infestation.
- Leaf spots: these bacterial/fungal diseases can usually be seen as sooty growths or spots on leaves — these will progressively turn brown with a yellow margin before eventually dying. Remove and dispose of any infected leaves.