IME a layer of perennial snippets works as mulch and keeps the worms happy.

It does not look very neat ( if that's an issue) and slugs can hide in it,

But I personally mulch with all the perennial stalk stuff and think it is great for the soil.

Do you have any trick to avoid cutting too low and damaging the base of the plants?

Happy mulching, bye, Lin

Thanks Lin! I appreciate your response. I thought probably it would be okay to leave it. And that is just what I will do. less work! :) I actually cut it to ground and I don't baby this catmint at all. It always comes back beautifully. I do this mid summer also. It always look like I destroyed the stuff but then its all back for the second show. I would not do this with other perennials but this catmint doesn't seem to be bothered by the harsh treatment. I love it!