Peach Leaf Curl Control

Symptoms

• The first signs of peach leaf curl are red warts, altered leaf color (yellow, orange or red) or severe leaf distortion. By the time these first symptoms have occurred, the infection has moved beyond the treatable phase and is within the leaves themselves. Fruits may also show warts, and at some point the peach tree may suddenly shed its useless infected leaves in a gambit to produce new, healthy ones.

Window of Opportunity

• Since peach leaf curl spores reside outside the plant until the buds start to swell, the best time to use fungicidal agents to prevent it is in fall or winter. Then there won't be spores to infect the susceptible buds in spring. Cool, wet springs keep the peach at its bud swell stage longer, leaving a longer window of opportunity for the peach leaf curl spores to get a foothold.

Other Prevention Methods

• Some varieties of peach and nectarine trees are resistant to peach leaf curl, such as Frost, Indian Free, Muir, Redhaven and Q-1-8 peach varieties or the Kreibich nectarine varieties. Planting in areas where there are no peach orchards and few or no peaches planted nearby means there's no host plant to keep the spores alive so they can spread.

Considerations

• There is a patent on the market that claims that a mixture of one part oregano oil to six or seven parts water sprayed on an infected peach tree will stop the symptoms of the disease and salvage the harvest for that year, though three applications would be needed. This claim has not yet been supported by research agencies and is not recommended by any agricultural extension agencies.