I need a weedkiller that doesnt promote grass growth. Have any ideas?

It cant be done. There are no weed killers that you put on desirable plants that will kill only the weeds unless the desirable plants are grasses and the weeds are broadleaf or you have full grown trees and want to kill the weeds around them. In that case you spray the weeds but not the tree. The only other answer is to prevent apply a chemical to keep the weed seeds from germinating around already established plants.

There are fescuecides that only kill certain grasses and can be applied over many plants but weeds are generally considered "broad leaf weeds" and most weed control products will kill the plants too. With weeds that have grown between plants you have to either pull them by hand or move/ cover the plants and spray the weeds individually with roundup. I've controlled infestations of thistles and bermuda grass in juniper and perennial beds with very little damage to the existing plants. It helps to have another person with gloves on to hold the plants back and use low spray pressure to avoid splashing and over spray.

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