Rheum rhabarbarum · Perennial
Slugs and snails: Use beer traps, copper tape barriers, or apply iron phosphate-based slug pellets.
Crown rot: Ensure soil is well-drained and avoid mulching directly over the crown to prevent waterlogging.
Aphids: Squash by hand, blast off with a strong jet of water, or use insecticidal soap if infestations are severe.
Honey fungus: Remove infected plants completely and avoid replanting rhubarb in that spot for several years.
Viral diseases: Remove and destroy infected plants immediately to prevent spread via tools or aphids.