Application of Insecticides Depends on the Label

Q. Please advise where I can find this borer control product you recommended to me for soil drenching. The product I found has only 1.47% imidacloprid in it. Is this strong enough for soil drenching?

A. This question opens a “can of worms” I tried to avoid earlier by only recommending a single product. Initially when evaluating a product for borer control as a liquid soil drench, two questions should be asked: 1. Does this product contain imidacloprid in the ingredients? 2. Do the instructions explain how to apply it as a soil drench to the type of plant I am treating? The instructions will tell you how to use it correctly.

Homeowner vs Professional Concentrations

            There is frequently a difference in concentrations of imidacloprid between “homeowner products” and “commercial products”. The obvious difference of course is availability to homeowners of commercial products but the other one is in the lower concentration that you mentioned.

            Homeowner products are frequently less concentrated than commercial products. This is because commercial applicators should have more knowledge about safe use of these pesticides and access to PPE (Professional Protective Equipment) when applying it. Plus, the homeowner uses less product.

            For commercial applicators, imidacloprid is contained in several products and atconcentrations much higher than 1.47%. “The dose makes the poison” and having a less concentrated product available to homeowners can be “safer” for the uninformed to use. It also means less “left over” product when finished.

Read the Label

            Is 1.47% strong enough to use as a soil drench?  Look at the directions for use. Does it say you can use it as a soil drench for your purpose? A reliable manufacturer will want you to be successful, tell others about your success and use their products again. A reliable manufacturer will give you the right instructions and concentration that will be effective.

This formulation of imidacloprid allow for a soil drench of vegetables and fruit trees. It has 0.233% imidacloprid and the label tells you how to mix and apply it. If the label doesn't allow it, then by law it is not allowed.

            It’s up to you to read the directions and make sure this product is applied correctly as a soil drench and for your purposes. Make sure it is applied after the plant flowers in the spring to avoid “honeybee” problems which it clearly states on the label.