Q: I am writing to inquire about recommendations for a nontoxic approach to controlling citrus leafminer on a young lime tree I am growing in a large pot.Β I do not recall having this pest in the past and have had limes, grapefruit and lemons for many years. This new lime tree I planted about a year ago is now infested on all the new leaves and I am wondering if there might be a nontoxic method to reduce or eliminate them. I have looked up information on the web but the recommendations seem to be relatively toxic and I would prefer to avoid those if possible.
A:Β Because your lime tree is young, insecticides are generally recommended to prevent these insects from slowing the growth of the tree. That said, you could let your tree tough it out since there are natural enemies that prey on the citrus leafminer and the leaves they damage are still effective food producers for the tree.
Other things you can do to manage the situation include avoiding pruning except for water sprouts and branches broken by wind, et cetera, and only fertilizing outside of the normal flights of the adults. The adults are most often seen in the summer and fall months. Both pruning and fertilizing promote the new growth that is most attractive to these insects.
Peter L. Warren is the urban horticulture agent for the Pima County Cooperative Extension and the University of Arizona. Questions may be emailed toΒ tucsongardensage@gmail.com
