Unfortunately there is no chemical (not even fancy organic stuff) available to control leek rust. After hours researching on line, all we could find was articles from commercial growers the world over wailing about how the professional fungicides they were using (so much stronger than the ones amateur gardeners can buy) were no use at all. As commercial garlic crops are affected by the same fungus, I have no doubt that the big multinational agrochemical companies are frantically working to find a cure, in the sure and certain knowledge that they will make billions from growers. So we can hope to see something in due course, but that's no consolation now.
- Rotate your crops properly. Leek rust also affects garlic, so bear that in mind when planning your planting. If you can remember to grow them in a different part of the patch when the rotation comes round again, that will give the soil double time to get rid of the spores.
- Don't use too much high-nitrate feed. Lush growth is more vulnerable
- Trim the tops of the leaves of seedlings before planting so they don't trail on the ground.
- Put plants in at a wider spacing to allow air to circulate and the leaves less like to touch each other, spreading the rust across the row.
- Pick off badly affected leaves.
- Give plants a liquid feed with a balanced fertiliser to help them cope with the lost leaves.
- Experts tip: to reduce leek rust problems, water leeks in the morning so the sun can dry the leaves. Water no more than necessary but don't let the plants go dry.