Question
Hello Jennifer:   I heard that a mixture of dishwashing liquid detergent and water sprayed on fruit trees will get rid of leaf miners.  Have you had any experience with this possible solution to this common problem?  If so - any details you can share about the mixture and how often to spray the trees?

Thanks for your feedback.

Terry.

Answer
Hi Terry,

There are many homemade products that you can try to control leaf miners or other insects.  Since these products have not been tested on a wide range of hosts, you may want to only treat a few leaves on the different types of trees you have and wait a few days.  Sometimes, homemade products will be mixed up too strong and can burn the leaves.  By treating and waiting a few days, you can be sure that your tree(s) will not be harmed by the mixture.

There are many different recipes that you can find on the internet if you search for homemade insecticide.  Products containing oil are usually effective for leaf miner control.  The dish soap sprays may also work, but an oil spray is probably a bit better.  A nicotine product may also work well.

The homemade sprays will not last very long.  Most commercial products have spreaders and stickers that help them adhere to the leaves so they do not need to be reapplied as frequently.  I would make an application and examine the trees in about 7 days to determine if repeated appliations are needed.  If no new infestations are noted, you can wait a few days and look again.  Scouting for new infestations will have to be continued throughout the growing season.  The homemade product may not be stable, so if you need to make a new application, I would recommend mixing up a new batch.

Remember that although these products will kill the insects, they will not cure the leaves of damage.  The leaves that were damaged by the leaf miner will still be present.  You will want to look at new growth to determine if new insects are attacking the young leaves.

Here are a few websites that I found, but there are many out there which all report success.  This is something that varies by location, type of plant and type of insect at how effective it is.  You will have to try it and see if it works for your problem.

http://www.annettemcfarlane.com/Doityourself.htm

http://www.catalangarden.com/homemade-pestcides-for-your-garden.html

Good luck with your plants!