Merit Insecticide Granules can be applied at any time, but if you are looking to control white grubs then you want to apply it several weeks before egg match of the target pest. Usually this application needs to be made in late Spring, usually sometime between May and late June. We recommend contacting your local Cooperative Extension for the best recommendation on application timing for your target pest in your area.
We do not know the setting for that spreader and we are not sure exactly what to set it on. However, almost all fertilizers, herbicides, insecticides, etc have treatments in amounts of so much product per 1000 square feet. So if you can figure out what your walking speed is then you know anytime you apply any product that calls for so much of it per 1000 square feet, you always set your spreader on this setting. You can calibrate this by marking off a 1000 square foot (10 x 100) area and placing 1.4 pounds of any type of product of similar granule size, or of the merit itself in the spreader. Start with a low setting and start walking your marked off area at a normal pace. You can adjust as you go and find the basic setting for you to apply the product over a 1000 square feet. The 60 pounds per acre equates to 1.4 pounds per 1000 square feet. Or, you can call Bayer, the manufacturer, and they may be able to tell you what setting you should have it on. You can reach them at (800) 331-2867.
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