There is no one size fits all answer for this as it largely depends on the product and your equipment.
Let's start with what equipment you are using. If you are using a pump sprayer or a backpack sprayer, you will want to water in the products that need it.
If you are using a hose-end sprayer, you are already getting some water down with the product. So now we must use some logic, if the product needs to be watered in you don't necessarily need to when applied with the hose-end sprayer since it was applied with extra water. However, it doesn't hurt to throw a little extra water on top to make sure the product really gets into your soil. Just don't go overboard and make a mess or wash away the product!
Now let's look at the Greene County products and see which ones need to be watered in:
You will also find this information on the product description pages towards the bottom:
So feel free to spray and pray all day… but if you are spraying products with iron in them (which can stain) then don’t spray right before a heavy rainstorm… you’re just asking for a mess everywhere! Other than that, be logical.
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