If you are getting ready to spray with multiple products and are not sure if they will be compatible, then to be safe, you should do a jar test. To perform a jar test, you will need to do the following:

  1. Determine the amount of water that your sprayer puts out per 1,000 square feet.
  2. Determine the rates per 1,000 square feet of all products that you will be mixing.
  3. Determine the formulation of each product that you will be mixing.

Once you have these three things determined, take a container that will hold the amount of solution required to cover 1,000 square feet and add to the container about ½ to 2/3 of the volume of water that is required to cover 1,000 square feet.

Then, in the same order that you will be adding the products in your spray tank, add each product’s rate per 1,000 square feet to the water in the container. Stir/shake or agitate the solution after each product is added.

Once all products are added, top off the solution to the total amount required to cover 1,000 square feet. Continue stirring/shaking or agitating thoroughly then allow the solution to sit for 10-15 minutes before evaluating.

Remember that the order in which products should be added to the spray tank depends upon their formulation. Oftentimes, this is referred to as the WALES method.

W 1st in the tank put Water Soluble Bags, Wettable Powders, Water Dispersible Granules


L  3rd Liquid Flowables such as Suspension Concentrates, Suspo Emulsions

E  4th Emulsifiable Concentrates such as Oil in Water Emulsions, Oil Dispersions

S  5th Solutions such as Soluble Concentrates, Liquid Fertilizers