Quick Guide: summer, hardy, full sun, height: 15-20cm/6-8in, width: 30cm/12in

There are several species of thyme suitable for the rock garden. The leaves of all of them are highly aromatic and two, Thymus vulgaris and T. x citriodorus, are used as culinary herbs (thyme is an essential ingredient in bouquets garnis). A perennial and very easy to grow, thyme spreads quickly and makes effective ground cover. The tiny flowers may be pink, red, lilac or white.

GROWING Plant from autumn to spring in well-drained garden soil. Full sun is important. After flowering snip off the faded flowerheads to encourage sturdy growth.

PROPAGATION Divide the plants in spring or late summer and replant at once directly in the flowering site.

SPECIES T. vulgaris, narrow, dark green, highly aromatic leaves, lilac flowers; T. serpyllurn (correctly known as T. drucei), grey-green, very spreading leaves, purple flowers; `Album' is a white form; `Pink Chintz' bears salmon-pink flowers; T. x citriodorus, lemon-scented leaves, short-lived lilac flowers; the leaves of `Aureus' are bright golden, those of `Silver Posy' silver.

POSSIBLE PROBLEMS Generally trouble-free.