Answer: Ajuga can potentially crowd out grass, but this usually occurs along the edge of a solidly planted bed of ajuga where the ajuga is extremely vigorous and "escapes". Ajuga would usually be planted 12 to 18 inches apart or maybe two feet apart on center for reasonably fast coverage of an area (about two years), and the area would have been first cleared of grass and the soil would have been prepared prior to planting. At this point you could either lift and replant the ajuga into prepared soil, or you could try the following. Mow the grass as short as possible or kill it with an herbicide containing glyphosate according to the label instructions. Cover the area with compost, then a thick layer of damp newspapers, then a layer of mulch. This mulch layer should keep the grass from growing back while you wait for the ajuga to grow. It will also rot down and help improve the soil a little bit. Meanwhile, water the ajuga and encourage it to grow out over the mulched area. Eventually it will fill in completely and prevent grass and weeds for the most part. Good luck with the ajuga project!
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