Randy writes
You did not indicate what you are trying to treat for so we can not give you a definitive answer. We will say that it is usually easier to prevent plant disease and plant damaging insects than it is to get rid of them after they have started damaging your plants so treatments should begin early. We recommend that you contact your local cooperative extension office and speak to the master gardener on staff. The master gardener is very well versed on the local flora and fauna in your region and will be able to tell you the proper time to start treatments on your plants.
Answer last updated on: 04/05/2011
