Symphyotrichum novi-belgii · Perennial
Powdery mildew: Ensure good air circulation, avoid overhead watering, and choose resistant varieties.
Slugs and snails: Use physical barriers like copper tape or apply iron phosphate pellets around the base.
Aphids: Spray off with a strong jet of water or use insecticidal soap for severe infestations.
Fusarium wilt: Remove and destroy infected plants immediately; avoid replanting asters in the same spot.
Leaf and bud eelworms: Remove affected plant parts and dispose of them; rotate crops to break the life cycle.