don't have the space to plant between my NE flagstone terrace. Would love to have Thymus serpyllum 'Elfin', but can't find seeds. Any suggestions? If not for Elfin, then of other very low-growing (1"high) hardys? Thanks, Dan.

I agree, you can divide the plant into very small (like half inch long and skinny) pieces and just stuff them in. Even a piece with no roots will root if you get some of the lower stem into some ground. It is so easy to propagate this way no one bothers with seeds. Be sure to weed well the first couple of years till it fills in. I do think Elfin thyme is a very good choice.