Q. My peach trees have leaf curl. All information I’ve been able to find indicates that there’s nothing that can or should be done once the tree has leafed out, but that when all the leaves have fallen off the tree (presumably in the autumn, although one of the two is dropping the most severely affected leaves already) it should be sprayed with a particular chemical (that I’ve been able to obtain from Lowe’s). Will it do any good to pick the affected leaves off right now? Should I do this? Can this problem kill a tree? Thanks for any help you can provide. Best, Steve Rodgers – Tacoma, WA
A. Well the fungal disease leaf curl has been the scourge of commercial peach growers in our area for years. Most commercial growers switched over to leaf curl resistant varieties like Frost. I am growing Q-1-8 from Raintree (a variety that kept its research designation – not a Star Wars droid), which has proven in my yard to resistant even in its youth (Frost can be affected when it is young but is resistant as it gets older). The recommendation is to spray fungicide during the dormant season since the spores overwinter on the bark of the tree. Then the spring rains move the spores to the new growing leaves. Once the spores have infected the leaves in the spring they cannot be treated. It would be helpful to remove any infected leaves now (in stages- so that the tree is not stripped of all its leaves at once) and any leaves that have fallen to the ground to reduce sources of new spores. Destroy the leaves (burning is best where allowed). In the short term the disease will not kill the peach tree, but it can weaken the tree leaving it open to other problems as well as reduce peach production. Be ready next dormant season so you can catch the disease in time.