What to mix w/RoundUp in rainy weather to kill weeds?
What should I mix w/RoundUp to get RoundUp to stay on weeds in the rainy weather?
Certified GKH Gardening Expert
Spraying or applying an herbicide in rainy weather is really not recommended. You need to wait for a time of clear weather between the rainstorms. You can add what is called a Spreader-Sticker product to the spray mix to help it spread out over and stick to the foliage. Go to a local garden center or nursery and tell them you need a Spreader-Sticker product to add to your plant spray mixes. It also works very well for use in application of insecticides and fungicides.