Deterring leaf curl in Peaches and Nectarines
Leaf curl is the most disfiguring of diseases, and unique to Peach, Nectarine and Almond. The leaves come out in this rather alarming red blisters and, to the uninformed, it looks like some boggling alien infection that ought to have you rushing for the face-mask.
Actually, it’s not quite as bad as it looks and is more cosmetic than killer. Usually by late summer it has gone away and often the trees still fruit. But it is undeniably unsightly and it does sap some of the trees strength so nit’s definitely a problem to be avoided.
Understanding the way it is spread is important to taking informed action on how to avoid it. The spores that spread the disease are active only in very early spring, and they are spread by water droplets and moisture. That’s why if the spring is a dry one, you may not get this disease at all. But during rains springs it is rife. Most years, if you grow peach and nectarine, you will see at least some blisters on the leaves.
The key is in keeping the trees dry during the critical period when the leaves are beginning to emerge. Trees that are grown in pots are easily dealt with, as you can simply move them into a greenhouse or conservatory for a week or two, until the foliage is fully developed, at which time the risk of infection has passed.
Trees growing in the open should be covered with sheeting if rain threatens, or maybe the industrious can provide a make shift frame covered with polythene that can be put in place for a week or two.
Trees grown under cover, in a greenhouse or sun lounge, are less susceptible for leaf curl, but they can still get it, especially if you water overhead. Make sure the leaves don’t get wet during this critical time, be meticulous in your watering and apply water only at the roots.