Overview
What thyme needs, how hardy it is, and whether it suits your garden.
Thyme grows wild on dry, stony Mediterranean hillsides, and it does best when you copy that: full sun, poor, free-draining soil and very little water. Sun brings the oils to the leaves and gives the flavour, and bees crowd the summer flowers. Treat plants as short-lived: after a few years they turn woody, and cuttings give you fresh ones.
Quick facts
- Botanical name
- Thymus vulgaris
- Soil pH
- 6.3 – 8.0
- Feeding
- Light feeder
- Hardiness
- USDA zone 5a and warmer
- Height
- Up to 30 cm (12 in)
- Propagation
- Cutting, Layering, Division, Seed
Survives −28 °C
Growing details
- Frost sensitivity
- Frost hardy
Growing calendar
- Start indoors: March, April
- Plant out: April, May, June, September
- Flowering: May, June, July
- Prune: April, May, July, August
- Harvest: January, February, March, April, May, June, July, August, September, October, November, December
In spring, in a temperate climate (RHS). In a temperate climate: mid-spring to early summer (RHS), or autumn (Gardeners’ World). June and July (Penn State); NC State gives May to July. Mid- to late spring and after flowering (RHS). All year (Gardeners’ World).
Is this plant right for you?
- Evergreen
- Drought tolerant
- Needs drainage
- Pick all year
- Good in pots
- Loved by bees
- Safe for pets
Good to know
It does well in a pot indoors or out, so you do not need a bed for it. It stands frost, so it can go out earlier than tender crops.
Before You Grow
Choose upright or creeping, culinary or ornamental, and the sunniest, driest spot you have.
Thyme is non-toxic to cats, dogs and horses (ASPCA).
What you need
Young plants
Faster than seed. See when to plant.
Full sun
The sunniest spot you have. See where thyme grows best.
Grit or gravel
For drainage and mulch. See soil.
A pot with holes
If your soil is heavy. See containers.
Scissors or shears
For picking and trimming. See trimming.
Choose your thyme
For cooking, choose a shrubby thyme; for paving and ground cover, a creeping one. Leaves come green, golden, silver or variegated, and flowers white, pink or mauve (Gardeners’ World, RHS).
Shrubby thymes form mounds up to 30 cm (1 ft) tall and are more practical to harvest (RHS). Common thyme (Thymus vulgaris) is the classic cooking thyme; ‘Narrow Leaf French’ is lighter and sweeter; ‘German Winter’ is very hardy (Penn State).
Lemon thymes have lemon-scented leaves: ‘Lemon Curd’, ‘Golden King’, ‘Silver Queen’ (RHS, Gardeners’ World, Penn State).
Caraway thyme has an earthy, caraway flavour; broad-leaved thyme has rounded, well-flavoured leaves (RHS).
Creeping thymes grow just 5 to 8 cm (2 to 3 in) tall: ground cover, paving cracks, rock gardens and thyme lawns. ‘Snowdrift’ has white flowers; woolly thyme has grey, furry leaves (RHS, Penn State, Illinois).
Hardiness. Most sold in the UK survive frost, but check the label: less reliably hardy types such as T. cilicicus are best in pots moved under cover for winter (RHS).
Thyme types compared
-
Common thyme
- Habit
- Mound, 15 to 30 cm (6 to 12 in)
- Flavour
- Sweet, earthy, peppery
- Best for
- Cooking, bouquet garni
-
Lemon thyme
- Habit
- Low mound
- Flavour
- Lemon
- Best for
- Fish, poultry
-
Caraway thyme
- Habit
- Low, spreading
- Flavour
- Caraway
- Best for
- Cooking, ground cover
-
Broad-leaved thyme
- Habit
- Bushy
- Flavour
- Well flavoured
- Best for
- Cooking
-
Creeping thyme
- Habit
- Mat, 5 to 8 cm (2 to 3 in)
- Flavour
- Varies
- Best for
- Paving, lawns, rock gardens
-
Woolly thyme
- Habit
- Grey, furry mat
- Flavour
- Ornamental
- Best for
- Rock gardens
From the RHS, Penn State and Illinois. For the kitchen, a shrubby common or lemon thyme.
Where thyme grows best
Thyme is a Mediterranean plant that thrives in warmth, sun and dry conditions (RHS, Gardeners’ World).
Sun. Full sun brings the essential oils to the leaves and gives the best flavour (Gardeners’ World). Penn State accepts partial shade.
Hardiness. Common thyme is hardy to about USDA zone 5, around −29 °C (−20 °F) (NC State, Penn State). Wet is the real threat: shelter plants from cold winds and wet winters (Gardeners’ World).
Neighbours. Don’t let thyme get smothered by vigorous plants or fallen leaves (RHS). It won’t thrive in mixed pots with thirstier herbs (Gardeners’ World).
Where. Herb gardens, gravel gardens, cracks in paving, path edges and rock gardens (Gardeners’ World, RHS).
- Sun
- Full sun
- Hardy to
- About USDA zone 5
- Height
- 5 to 30 cm (2 to 12 in)
Soil
Light, free-draining soil that’s low in nutrients (RHS, Gardeners’ World). NC State finds it best in dry, sandy or rocky soil; Illinois differs, preferring soil well amended with organic matter, as long as it drains.
Heavy or damp soil. Roots rot, especially in winter. Grow thyme in a raised bed or a container instead (RHS).
pH. Neutral to alkaline; Penn State gives 6.3 (NC State, Penn State).
Mulch with grit or gravel: it suppresses weeds and lifts the stems off damp soil (RHS).
Planting
When to plant, raising thyme from seed, and planting it out.
Harden off indoor-raised plants before planting them out (RHS).
When to plant thyme
Plants settle in best from mid-spring to early summer (RHS); Gardeners’ World also plants in autumn on free-draining soil.
Young plants are widely sold and establish more reliably than seed (Gardeners’ World).
From seed, sow indoors in spring. The RHS expects about a year before you can harvest; Penn State says it may take several years.
- Mid-spring to early summer.
- Young plants over seed.
- Harden off first.
Growing thyme from seed
Seed is cheap for lots of plants, such as edging or ground cover, but germination is uneven and plants are slow (RHS, NC State).
-
Sow on the surface
In spring, thinly on moist seed compost. Don’t cover the tiny seed (RHS).
-
Keep warm
At 15 to 20 °C (59 to 68 °F), somewhere bright. Seedlings appear within a couple of weeks. Water regularly but not too much: seedlings are prone to damping off (RHS).
-
Pot on
When seedlings have several leaves, move each to a 7.5 cm (3 in) pot of loam-based compost (RHS).
-
Plant out
Once well rooted. First harden off: stand pots outside by day and bring them in at night for a week or two (RHS).
How to plant thyme
Drainage decides how long thyme lives.
-
Pick the spot
Warm, sunny and sheltered, in light, well-drained soil (RHS).
-
Heavy or damp soil?
Plant in a raised bed or a container instead (RHS).
-
Space the plants
20 to 30 cm (8 to 12 in) apart, depending on the variety (RHS, UMD).
-
Plant at the same depth
As in the pot, in the lightest, best-drained soil you have, then water in (RHS, Gardeners’ World).
-
Mulch with grit
Especially under creeping types (RHS).
Care
Watering, feeding, trimming, and growing thyme in pots or indoors.
Too much water is a bigger risk than too little: roots rot in damp, especially in winter (RHS).
Care by season
Spring
Cuttings: new growth
Trim lightly and plant new thyme. See trimming.
Early summer
Pots: water in dry spells
Best harvest, just before flowering. See harvesting.
After flowering
Bees: flowers feed them
Trim off faded flowers. See trimming.
Autumn
Layering: peg low stems
Clear fallen leaves off plants. See growing conditions.
Winter
Wet: cloche or move pots
Keep the roots dry. See containers.
Watering thyme
Thyme is drought tolerant and rarely needs watering once established (RHS, Gardeners’ World).
New plants. Keep them moist while young and settling in (RHS, Penn State).
Pots. Water in hot, dry weather, when the compost has dried out, and keep it on the dry side (RHS, Illinois).
Too much is the bigger danger: roots rot in damp soil, especially in winter (RHS).
Feeding thyme
Thyme grows best in soil low in nutrients and needs no fertiliser once established (Gardeners’ World, Penn State).
Pots. Gardeners’ World gives potted thyme a weekly liquid seaweed feed from March to May.
Trimming thyme
Regular light trimming keeps thyme compact and bushy and gives more fresh leaves (RHS, Gardeners’ World).
Shrubby thymes. Trim lightly in mid- to late spring and soon after flowering (RHS).
Creeping thymes. A very light trim after flowering to remove the spent flowers (RHS).
Old wood. Stems cut back hard into old wood may not regrow, so the RHS usually replaces old plants; Illinois instead cuts old plants back hard in spring to force new stems.
Lifespan. Unpruned plants turn woody and need replacing after about three years (Gardeners’ World). See propagation.
- Light trims only.
- Spring and after flowering.
- Replace woody plants.
Thyme in containers
Thyme grows well in pots, which give it the drainage it likes (RHS).
Pot. At least 15 cm (6 in) wide and 10 cm (4 in) deep per plant, with plenty of drainage holes (RHS).
Compost. Soil-based compost with up to a quarter grit by volume (RHS, Gardeners’ World). Raise the pot on feet (Gardeners’ World).
Winter. In wet winters, move pots to a rain shadow near a building; less hardy types go into a greenhouse or porch (RHS).
Thyme indoors
Thyme is an outdoor plant; indoors is for winter.
For picking. Pot thyme up in autumn and grow it on a bright, sunny windowsill through winter, watering sparingly (Illinois).
For shelter only. Gardeners’ World brings outdoor pots in for winter to escape the wet and doesn’t water them at all until they go back outside in spring.
Light. As bright as possible; thyme wants full sun.
Problems
Winter wet, old woody plants, and a few pests.
Common thyme problems
Thyme rarely suffers from pests or diseases (Gardeners’ World).
Dying over winter
- Wet
- Root rot
Cold, wet soil rots the roots. Improve drainage, use a cloche in wet areas, or grow it in a pot (RHS, Gardeners’ World).
Woody, straggly plants
- Age
- No trimming
Trim yearly and replace plants every few years (RHS, Illinois). See propagation.
Weak flavour
- Shade
- Rich soil
Grow it in full sun in lean soil (Gardeners’ World).
Foliage rotting at the base
- Damp
- Smothered
Leaves lying on damp soil can rot. Lift them off it with a grit mulch and clear fallen leaves (RHS).
Plants not true to type
- Self-sown seed
Seedlings of named varieties vary (RHS). Propagate vegetatively.
More problems with thyme
Diseases and pests
Rosemary beetle
Metallic green and purple beetles and grey larvae eat the leaves. Damage is rarely severe; pick them off (RHS, Gardeners’ World).
Sage leafhoppers
Coarse, pale mottling on the leaves in spring and summer. Rarely serious (RHS).
Slugs, snails and spider mites
Slugs and snails eat young shoots (RHS). Spider mites and fungal diseases also occur (Penn State). For root rot, see dying over winter.
Harvest & Use
Picking, drying and cooking with thyme.
Harvesting thyme
Thyme is evergreen, so you can pick it all year, but soft new growth in late spring and summer tastes best (RHS). Regular picking keeps plants bushy.
Best time. Just before flowering, in early summer, when the oils peak (Gardeners’ World, NC State). Pick on a dry day after the dew has dried and before midday (Penn State).
How much. Cut the leafy tops, 12 to 15 cm (5 to 6 in), and leave the woody stems with at least 12 cm (5 in) of growth (NC State).
Flowers taste like the leaves and add colour to salads (RHS).
- All year, a little at a time.
- Best just before flowering.
- Leave the woody base.
Drying, storing and using thyme
Drying. Hang small bundles upside down somewhere warm, dark and airy for a few weeks. When the leaves are crisp, strip them into an airtight jar (RHS, Penn State). Dried thyme keeps a strong flavour.
Butter and vinegar. Gardeners’ World preserves thyme in flavoured butter or vinegar.
Cooking. Thyme holds its flavour through long, slow cooking: stews, soups, stuffings, poultry and bouquet garni. Lemon thymes suit fish (Illinois, Gardeners’ World).
Propagation
Three ways to make new plants from the ones you have.
Propagating thyme
New plants from cuttings, layers or division match the parent (RHS); seed from named varieties doesn’t come true.
Cuttings. In spring or early summer, take 10 cm (4 in) tips of new growth and insert them into pots of sand (Penn State). Keep them moist and bright but out of direct sun, and pot them on once new growth shows they have rooted.
Layering. In spring or autumn, peg low stems into the soil to root; check round the edge of old plants, where it often happens naturally (RHS). Once rooted, cut the new plant from its parent and replant it.
Division. In spring, lift an established plant and split it into pieces with roots, and replant them at once and water in. Best for creeping, mat-forming thymes (RHS, Penn State).
More to Explore
Short answers, guides that pair well with thyme, and the sources behind this one.
Frequently asked questions
How often should I water thyme?
Rarely once established; only new plants and pots in hot weather. See watering.
Why is my thyme turning woody?
Age and no trimming. See trimming.
Can thyme survive winter?
Most thymes survive frost; wet soil is what kills them. See growing conditions.
Can I grow thyme from seed?
Yes, but it’s slow and uneven; young plants are faster. See growing from seed.
Can I grow thyme indoors?
Through winter, on a bright, sunny windowsill, watered sparingly; it does best back outside. See thyme indoors.
When is the best time to harvest thyme?
Any time; the flavour peaks just before flowering. See harvesting.
Is thyme safe for cats and dogs?
Yes, the ASPCA lists it as non-toxic to cats, dogs and horses.
Can I grow thyme between paving?
Yes, creeping thymes suit paving cracks and path edges.
Related guides
Sources
- How to grow thyme (opens in a new tab) Royal Horticultural Society
- Thyme (opens in a new tab) ASPCA Animal Poison Control
- Herb garden plants: thyme (opens in a new tab) Penn State Extension
- Thyme (opens in a new tab) University of Illinois Extension
- Thyme (opens in a new tab) University of Maryland Extension
- Thymus vulgaris (opens in a new tab) NC State Extension Gardener Plant Toolbox
- How to grow thyme (opens in a new tab) BBC Gardeners’ World