Thyme (Thymus) is a compact evergreen shrub with small aromatic leaves. It’s easy to grow in a warm, sunny spot, in free-draining soil or containers. It’s also drought tolerant and needs little maintenance once settled in.
Thyme is an attractive essential for any herb garden, where it teams well with Mediterranean herbs such as lavender, sage and hyssop, which like similar growing conditions. It also makes an attractive, fragrant edging for sunny veg beds, Mediterranean-style borders and gravel garden.
As thyme is evergreen, you can pick sprigs all year round, although the new growth in spring and summer has the best flavour. You can use the leaves fresh or dried in many dishes, and they’re a key ingredient in traditional bouquet garni and herbes de Provence. The flowers are also edible.
Month by Month
There is a wide choice of thyme varieties, with delicious scents and flavours, often with hints of lemon or orange. The leaves also come in various shades of green and yellow, or variegated with silver or gold. The clusters of tiny flowers may be pink, red, purple, mauve or white, depending on the variety, and are always much loved by bees. Thymes can vary in hardiness and size, reaching no more than 30cm (1ft) tall and often much less, forming aromatic groundcover in sun-baked spots.
When choosing varieties, look for those with an RHS Award of Garden Merit (AGM), which shows they performed well in trials. You can also see many culinary herbs, including thyme, growing in the herb collections in the RHS gardens, so do visit to compare the varieties and scents, and pick up useful tips.
What and where to buy
However, the quickest and easiest option is to buy young plants or established plants, which are available throughout the year from most plant retailers. Herb nurseries offer the widest choice of varieties.
But you don’t have to buy thyme plants of course – you can grow your own from cuttings. Use a thyme plant you already have, or ask gardening friends if you can take cuttings from theirs. See our guide to propagating herbs.
Thyme can be grown from seed sown indoors, as well as from cuttings, or can be bought as young plants and more established plants. This herb likes a warm sunny spot and light free-draining soil.
Once the seedlings are large enough to handle, move them into individual pots or modules, keep in a warm, bright spot and water regularly. They can be planted outside once they’re well rooted and growing strongly. See Planting, below.
Thyme grown from seed may take a year or so to get established enough for you to start harvesting the leaves.
Home-grown and bought thyme plants are best planted in late spring and early summer. Thyme can also be planted at other times, but avoid extremes of hot or cold weather.
Indoor-grown plants should be gently acclimatised to outdoor conditions by hardening off before you plant them outdoors.
Choose a warm, sunny planting site with light, well-drained soil. If your soil is heavy or stays quite damp, especially in winter, then plant thyme in containers or raised beds instead, where drainage will be better. Space plants 20-30cm (8-12in) apart, depending on the variety.
As thyme quickly becomes woody, it’s best to replace plants every three years or so, once they start to look straggly. Luckily it’s easy to take cuttings or to root low-growing stems to grow replacement plants for free.
Water newly planted thyme regularly for the first few months, until well settled in.
Also water plants in containers during hot summer weather, as their potting compost will dry out very quickly.
Established thyme plants in the ground are drought tolerant and rarely need watering. In fact, too much water is more of a problem – thyme hates damp conditions, especially in winter, as it can cause the roots to rot. So be sure to choose a planting spot with free-draining soil or grow it in a raised bed or container.
Plants in containers should be protected from excessive winter wet by moving them into a sheltered spot, where they won’t get soaked by heavy rain.
Spread a layer of grit or gravel around thyme plants, especially trailing types. This not only looks attractive, but also lifts low branches and foliage off damp soil, which could otherwise cause rotting.
Thyme grows best in poor soil and doesn’t need any additional feeding.
Keep the soil weed-free, as these low-growing plants are easily swamped or shaded out by vigorous weeds.
Thyme thrives in warmth and sunshine. Most widely sold varieties can withstand frost and British winters, but do check before buying. The less hardy varieties are best either grown in containers and moved indoors over winter, or covered with cloches in frosty weather.
All thymes dislike damp conditions, especially in winter, which can cause the roots to rot. So avoid planting in soil that stays damp over winter – instead plant in a raised bed or container. Move containers to a more sheltered spot over winter, out of heavy rain.
To make new thyme plants that will be exactly the same as the parent plant, take cuttings in late spring or summer. Use thyme plants you already have, or ask friends if you can take cuttings from theirs.
Another easy option is to pin low-lying stems into the ground to root, known as layering. This often happens naturally with ground-hugging varieties, so look around the edge of the clump in spring and if you find any well-rooted stems, these can be detached and potted up as new plants.
Thyme can also be grown from seed collected from your own plants, if you leave the flowers to form seeds. Just bear in mind that plants grown from the seeds of a named variety may not turn out exactly the same as the parent – if you want identical plants, take cutting or root low-lying stems (see above).
Pruning and Training
Thyme should be clipped back after flowering with shears or secateurs to keep it compact and bushy with lots of fresh new leaves. Just trim the leafy stems to encourage fresh growth – avoid cutting back into the older part of the stems.
Left untrimmed, thyme will soon become straggly, sprawly and woody at the base. And even when clipped annually, thyme is best replaced every few years with younger, better-looking plants full of fresh leafy growth. Luckily, it’s easy to grow new plants for free, using your existing ones – see Propagating, above.
Use scissors to snip off young shoots whenever needed, taking care not to spoil the shape of the plant. Regular harvesting helps to keep thyme compact and bushy, and encourages lots of new growth.
The leaves can be used fresh or can be dried for later use.
To dry, hang up sprigs in a warm, dark, well-ventilated place. When fully dried, store the leaves in an air-tight jar.
Thyme leaves bring delicious Mediterranean flavour to many dishes, including pasta sauces, stews, roast meats, vegetables and herb breads. Lemon-flavoured varieties go particularly well with fish and chicken. Fresh leaves can also be sprinkled into salads.
You can also use the tiny flowers to add colour to leafy salads and sauces, as they have a similar flavour to the leaves.
Once established, thyme is usually trouble-free, if grown in a suitably warm, sunny location. It also needs free-draining soil or potting compost that doesn’t get waterlogged. So ensure plants are not exposed to cold, damp soil conditions over winter, as they may not survive.
Thyme doesn’t usually age gracefully – plants tend to become straggly and woody after a while, so it’s usually best to replace them with new ones after a few years. This will ensure you get continued harvests of fresh leaves on attractive, compact plants. See Propagating, above.
Few pests and diseases affect thyme, but its leaves can be damaged by rosemary beetles and sage leafhoppers. These don’t generally cause severe problems though, so control isn’t necessary. Simply pick off any affected leaves if you prefer.
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