These are the most forgiving
Woolly thyme likes to stretch its flat branches out over sidewalks and stairs. It is useful in softening the lines described by hardscaping materials like brick and concrete.
Ornamental thymes (Thymus spp. and cvs.) are probably one of the most forgiving groups of plants when it comes to foot traffic. Woolly thyme (T. pseudolanuginosus, USDA Hardiness Zones 5–9), a 1-inch to 3-inch-tall ground cover, is good for use in a walkway since it grows flat. Its minute gray leaves really are woolly, or pubescent, and give the plant an all-over soft and fuzzy appearance. In mid- to late June, pale mauve flowers top woolly thyme like frosting smeared casually on a cupcake. However, the blossoms do attract bees. Gardeners who are wary of those nectar-loving insects may want to site these plants with caution.
Like other thymes, woolly thyme is fairly easy to care for. It requires very little water once it has become established, and as for cutting it back, just an annual haircut tidies it up and promotes fuller growth. Give it full sun and welldrained soil and it won’t disappoint you. Another top-notch plant that stands up to regular foot traffic is an unusual evergreen called brass buttons (Leptinella squalida, syn. Cotula squalida, Zones 4–7). A native of New Zealand, this plant grows to 2 inches high and forms a creeping weed-proof mat. Its foliage looks like tiny, delicate fern fronds.The hybrid ‘Platt’s Black’ (L. squalida ‘Platt’s Black’, Zones 4–7) has bronze leaves with a decidedly dark midrib. Both plants like part shade and prefer regular water during dry periods.