Sunday, May 10, 2020

Peach Leaf Curl


I love peaches, do you love peaches? My mother, her mother and my daughter and I have all delighted in peaches and nectarines until I moved to a different climate and Peach Leaf Curl turned up on my trees. Peach leaf curl is a pathogenic fungi affecting peaches and nectarines. It is easy to identify through leaf discoloration and malformation of leaves.  It can also affect branches if not cared for and eliminated early in the life of the tree. Eventually trees will die if trees are not cared for. The goods news… Peach Leaf Curl can be treated. The Latin name of the disease is Taphrina deformans.

Look for puckering, and actual curling in the leaf. Leaves will have multiple hues of pink, plum, red and yellow discoloration. One will also look for thickening of leaves as leaves begin to open in spring, generally the first 2 to 3 weeks. If a tree is affected you will eventually see the fungus as the first leaves are completely formed in the spring.  Eventually leaves will turn grey and brown and either remain or fall from the tree.  Be sure to pick up and discard all affected leaves and branches, do not compost. 

How Peach Leaf Curl infects and is transmitted: The fungus overwinters on the buds and twigs of the host tree. Germination of the spores begins in spring and is dependent on rainfall. Frequent periods of rain in spring, as peach and nectarine buds are opening will lead to the infection as the fungus is already present. When rain does not occur little to no infection will occur. Spring temperatures of 40 to 65 F and .5 inches of rain fall or more are the perfect combination for Peach Leaf Curl fungus to be formed and carried to other trees by wind. The infection only occurs on new leaf and bud production. If left untreated new spores will remain on the buds and spread to twigs and branches. The cycle will repeat itself the following spring.  

You will want to avoid excessive fertilizer and be sure to water trees correctly throughout each season.  If there is a drought be sure to water your trees to be sure they do not get stressed.  Be sure not to over water if you have excessive rainfall. One will want to water approximately 2 to 3 times per week depending on the rain and temperate in order to penetrate the soil down to 10 inches. Fungicides are available to treat Peach Leaf Curl however, timing is very important. When the tree is dormant in late fall or early spring before buds swell is the time to apply.  Be sure to read the label completely prior to any application. The fungicide you purchase should be labeled for use on edible fruit. Peach leaf curl can be prevented by purchasing resistant varieties.

There you have it, treat your trees and enjoy your peaches.