Thyme

Sow in a seed tray or directly in the bed in spring, in light well-drained soil at about pH 6.3, and thin the seedlings to 12 inches apart. Seed-grown plants take several years to reach a size worth harvesting, so if you want thyme this year, start from a division or a cutting rather than seed. Thyme germinates slowly and builds its woody frame over several seasons, so a seedling spends its first years making structure rather than the leafy stems you actually cut.

In spring, lift the entire root ball of an established plant and pull or cut it into smaller pieces, making sure every piece keeps rootlets attached, then replant them at the depth they were growing. Do this every few years as the clump ages, rather than waiting for the old plant to die out. Division is far more reliable than seed for thyme and it resets a clump that has gone woody in the middle, giving you young rooted plants from wood that would otherwise be spent.

Trim the plant back in early spring to limit woody growth and force new shoots, and trim again through summer whenever it goes leggy. Every few years, when the base has gone bare and twiggy, cut the whole plant back severely in spring to renew it. Thyme is a subshrub - the oldest wood at the base stops producing leaves and will not resprout well once it is bare, so the plant slowly hollows out unless you keep forcing young tender stems from lower down.

Take the main drying harvest as the flower buds swell and show color but before they open - this is when leaf essential oil content peaks. Cut five to six inches off the top growth, leaving the woody stems below. Gather on a dry morning after the dew has burned off. Strip the bottom two inches of leaves, bundle the stems, and hang them upside down somewhere shady, dry, and airy until crisp, then store the leaves in an airtight jar. The essential oil in the leaves peaks just before the plant flowers and falls off once it blooms, so the same cut made after the blossoms open carries noticeably less flavor. Dew left on the stems invites mold in the drying bundle.

Let the soil dry out between waterings, then water deeply rather than sprinkling often. Thyme wants fast-draining sandy or rocky ground and full sun; if yours sits in heavy soil, raise the bed or work in grit rather than watering less on bad drainage. Thyme is drought-tolerant and intolerant of wet feet - constant moisture around the roots brings on root rot, and poorly drained ground, especially over winter, is what shortens most plantings' lives rather than cold.