I have a path with flagstone, with the gap between the stones being around an inch or so. I've had creeping thyme growing between the stones, but it's been a huge battle keeping other plants, specifically clover (which I think may have already been living in the thyme plants when I brought them home from the nursery). I've spent quite a bit of time pulling up the invaders and as much of their roots as possible, but it's been a very time-consuming process. I'm worried that the clover might crowd out the thyme, which hasn't always been as hardy as I'd like.
Anyone have any pointers on maintaining healthy, mostly weed free ground covers, especially gap-filling plants? Any hints on blocking or retarding the growth of invaders? Or should I give up on this plant and try to find something that's going to grow more aggressively in this space (clover seems to like this location)?
Also, I'd prefer to stick to an organic solution and not use any harsh chemicals.