Q How can I stop leeks rotting on my allotment?
A ANNE SAYS Leek rust is a fungal disease and its first obvious symptoms are raised, slightly elongated orange spots on the foliage. There is no chemical control, even if you wanted to use it, so the best tactic is avoidance. Dispose of all infected material. On an allotment there are probably leeks and attendant rust spores all the time so there will always be a risk of infection. Some varieties have stronger resistance: ‘Porbella’, ‘Below Zero’, ‘Neptune’ and ‘Autumn Giant 2 – Porvite’ are good examples. Don’t add too much nitrogen-rich fertiliser as soft growth is more vulnerable; give a high-potash fertiliser instead, to strengthen growth. Generous spacing also helps so there is plenty of air circulation.