Answer: Certain marigolds repel nematodes from the soil, but in my experience they have not helped with the critter problem. You might try using a home-made or commerically produced pepper or pepper/garlic spray, or one of the commercially formulated repellents. Some gardeners report successs sprinkling bloom meal around the plants, too. However, in my experience, the best method is to use a wire mesh fence and run it not only up but also outwards just under the soil surface to thwart them digging their way in. You might also consider live trapping and removing them, although I would call in a professional to help with the ground hogs since they are really nasty and can be very dangerous.
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