Creeping Charlie: identify it, treat it, keep it out

Creeping Charlie is a mint, and it behaves like one: square stems, that minty smell when you mow it, and an aggressive creeping habit. Every runner roots wherever a node touches soil, so a single plant becomes a network of dozens of rooted crowns sharing resources. Spray one section and the surviving crowns refill it. Rip a mat out by hand and every fragment you miss re-roots. Its waxy leaves shed casual herbicide applications too, which is why generic weed-and-feed rarely dents it.

It also plays a different climate game than most lawn weeds: it prefers the moist shade where grass is already weakest, blooming purple in spring and expanding steadily in conditions where turf can barely photosynthesize. In deep shade, the competition is simply unfair.

Chemically there is one right answer: a triclopyr-based selective herbicide in fall, ideally after the first light frost when the plant is moving reserves to its roots. Coverage matters more than concentration, and a repeat the following fall is normal for established mats. Skip the borax home remedy; the effective dose is nearly the grass-damaging dose, and extensions stopped recommending it years ago.

Then change the habitat, or it returns. Limb up trees to add light, dial back irrigation in shady zones, and raise the mowing height so grass can hold ground. Where a corner will always be damp shade, plant it to a shade groundcover or mulch it deliberately. That is not surrender, it is refusing to referee an unwinnable match every single year.