Watch for Citrus Leafminer
Citrus leafminers have been regular visitors to Tri-Valley gardens over the past few years. They burrow into the citrus leaf and cause extensive damage to tender new growth. The leafminers thrive in the fresh new growth that is occurring now. Leaf
Leafminers originate when the tiny adult moth lays her eggs, they hatch, and the leafminer or larva burrows below the leaf surface. Hiding out between the upper and lower leaf surfaces makes Leafminers hard to control with sprays. Younger trees are especially vulnerable. Older trees, having a lot of older, tougher leaves should be fine without treatment but younger trees can be especially hard hit as most of their leaves are susceptible to damage.
As we come up on that time of year when prevention can be the best cure, we are getting the word out regarding what can be done to lessen the negative impact while there is time to take preventative steps.
Discouraging an over- abundance of new growth can be helpful in reducing damage. Plants that are watered more than 2x a week, and those receiving excessive fertilizing are more likely to produce the soft foliage that leafminers favor. Our grower recommends a steady, light supply of citrus food monthly as opposed to heavier feedings 3 times a year, as is common.
Hanging Leafminer traps can be an effective tool for knowing when to spray… hang traps in at least one of your citrus trees and monitor frequently so you can spot the arrival of adult moths.
Of greatest concern when applying any pesticide is protecting bees. Only apply pesticides after the citrus trees have bloomed so bees are not drawn to pollen while the tree is being treated. Citrus trees, for the most part, have long past their bloom period now, but pinching out flower buds if they appear after spraying will prevent the bees from visiting a plant that has been treated.
Citrus trees are clothed in new foliage. Watch for activity then spray every 10-14 days. Watch closely for leafminer activity and pinch out effective leaves as soon as damage is detected.