LEEK TROUBLESHOOTER

Q What’s causing orange blisters on the foliage?

A Leek rust is a fungal disease that results in rustcoloured spots on the leaves of leeks, garlic, chives and onions. Severe infestations prevent plants from thriving and the foliage becomes unsightly. Choose a rust-resistant cultivar and ensure they aren’t stressed from a shortage of nutrients or water, or overcrowded. Don’t put infected foliage on the compost heap.

Q Why are plants flowering?

A Leeks are biennial and it’s natural for them to flower once warm weather arrives in their second spring. Plants that bolt earlier may have been exposed to a spell of cold weather when very young. Protect early sowings from chilly spells, or wait until early April when there’s less chance of temperatures dipping. Harvest them quickly and cut out

and discard the central flower stem.

Q What is tunnelling into leaves and stem?

A Small brown adult leek moths lay eggs on leek leaves in spring and emerging caterpillars burrow into the foliage before moving on to the main shaft of the leek, damaging the plant and encouraging rot. Cover plants with a fine insect mesh until late September when the threat has passed. Caterpillars pupate near the plants and emerging adults then overwinter in the soil/leaf litter, so rotating

crops helps reduce the problem.