What's eating my king richard leek?

King Richard leek is most threatened by allium leaf miner, whose maggots tunnel straight into the white shank. Leek moth caterpillars skeletonise leaves, and onion thrips cause silvery scarring. Slugs attack young transplants at soil level. Row covers from planting are the single most effective preventive measure for this variety.

Rows of white stipple marks then larvae tunnelling deep into the shank, causing rot and unmarketable stems Cover with fine insect-proof mesh immediately after transplanting; remove and bin (do not compost) affected plants

Windowed, skeletonised leaves where caterpillars have eaten the inner tissue; frass visible inside rolled leaves Apply Bacillus thuringiensis (Bt) spray targeting young caterpillars; use pheromone traps to time sprays; row covers prevent egg-laying

Silver-white flecking along leaf length; leaves may twist or die back at tips in dry weather Insecticidal soap or spinosad spray; keep plants well watered as stressed plants are more susceptible

Ragged holes in young transplant leaves and at soil level, worst in wet weather Use ferric phosphate pellets around transplants; set beer traps; clear debris to reduce daytime hiding spots