Answer: There are not too many weed killers listed safe for cactus so I would opt for pulling the weeds and then covering over the soil with either weed barrier or several thicknesses of newspapers then covering over that with gravel. This will keep weeds from growing between the cacti. If you want to use a herbicide, Vantage, Manage or Image will work. Be sure to read the labels to make sure the product is safe to use around cactus.
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