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Couch grass often grows in among cultivated plants. It's a clump-forming perennial that spreads through the soil via underground stems or stolons, and is easily spread by cultivation. It can creep from lawns to infest flower and vegetable beds. Couch also produces flowerheads that are followed by seeds, allowing the further spread of this weed.
Solution
Organic
Dig out all the roots and underground stems of this grass, especially at the edge of infested lawns. Where couch is growing in permanently planted borders, it's easier to lift all the plants and tease out the weed from the rootballs. Regular slashing of the grass with a sharp knife will further weaken and loosen the plant.
Chemical
Use a systemic weedkiller on couch grass in spring. Re-apply throughout the growing season at four- to six-week intervals.
