Mediterranean shrub
How to grow rosemary
Salvia rosmarinus (syn. Rosmarinus officinalis)
Rosemary is an evergreen shrub that needs full sun and sharply drained soil, and very little else. Plant pot-grown rosemary in April or May, or in September on light soil, forking grit into heavy ground first. It is hardy to about minus 10°C when its roots are dry, and it is wet soil in winter, not cold, that kills most plants. Trim it lightly after flowering each year, never into bare wood, and do not feed plants growing in the ground.
- Hardiness
- Frost-hardy to about −10°C in free-draining soil
- Position
- Full sun, sheltered
- Soil
- Sharp-draining, gritty, lean
- Ideal pH
- 6.0 to 7.5
- Water
- Low, drought-tolerant once established
- Feeding
- Light feeder
Sowing and planting rosemary
WhenPlant Apr to May or Sep; harvest year-round; trim after flowering in late spring
Starting off
Plant pot-grown stock Apr to May, or Sep on light soil. Semi-ripe cuttings 8 to 10 cm long taken Jul to Sep, lower leaves stripped, root in gritty compost in 4 to 8 weeks and are the easiest route. Seed germinates in 14 to 28 days at 20°C but takes two years to make a useful plant. Low stems can be layered in spring.
Spacing and planting
Plant specimens 60 to 90 cm apart (eventual spread 1 to 1.5 m) or 45 cm apart for a hedge, in a hole no deeper than the pot with a third of grit forked into the backfill. Fine in a 30 to 40 cm pot of loam-based compost with 25 per cent grit.
Varieties worth growing
- Miss Jessopp's Upright
- Tall, straight and among the hardiest. The usual choice for a rosemary hedge and for long skewer stems.
- Tuscan Blue
- Upright, with broad, juicy leaves and deep blue flowers. Fine flavour, but give it a warm wall in colder gardens.
- Sissinghurst Blue
- A bushy, free-flowering plant to about 1.2 m, covered in rich blue flowers in spring. Good as a single specimen.
- Prostratus Group
- Trailing rosemary for the top of a wall or the edge of a large pot. Less hardy than upright types, so it needs shelter and perfect drainage.
Rosemary month by month
Timings are for central England. Allow two weeks later in the north and on cold, heavy soil.
- January
Pick as needed. Knock heavy snow off the branches so they do not splay.
- February
Pick as needed. Check pots are raised on feet and draining.
- March
First flowers open in mild gardens. Leave the plant alone until flowering is over.
- April
Plant. Cut out any winter-killed shoots once you can see new growth. Light feed for pot plants only.
- May
Main flowering, busy with bees. Plant. Layer low stems by pegging them into gritty soil.
- June
Trim after flowering, taking a few centimetres off the green shoots and leaving leaves below every cut. Clip hedges.
- July
Take semi-ripe cuttings 8 to 10 cm long. Water plants set out this spring in dry spells.
- August
More cuttings. No trimming from now on, so new growth hardens before winter.
- September
Plant on light soil. Start checking for rosemary beetle. Pot up rooted cuttings.
- October
Move pots to the foot of a sunny wall, out of the rain if possible. Remove saucers.
- November
Pick as needed. Shake off beetles on mild days.
- December
Pick sprigs for the kitchen. Fleece trailing varieties in a hard frost.
Feeding rosemary
A very light feeder. In the ground it needs no fertiliser at all; rich soil makes soft growth with less scent that is more likely to die in winter. Only a plant kept for years in the same pot needs help.
Very low, rich or wet soil rots it and dilutes the aroma. Mimic a dry hillside.
Feeding plan
In the ground, at any time
No fertiliser
Nothing. Spend the effort on drainage: fork a third by volume of grit into the planting area on heavy soil.
Pots, April, from the second year in the same compost
1 ml per litre of compost, the low end of the label's monthly top-dress, applied once: 20 ml, four level teaspoons, for a 35 cm pot holding 20 litres.
Pots, May and June, only if growth is pale and sparse
1 g per litre of water as a drench, two or three times, three weeks apart. Stop by the end of June.
Signs to watch
Pale, sparse growth after three years in one pot
Nitrogen short
Repot or a light balanced feed in Apr
Young leaves yellow between green veins under hard tap water
Iron locked by high pH
Rainwater
Pests, diseases and problems
Shoot tips eaten and browned from late summer through to spring, with small metallic beetles striped green and purple, or grey grubs, on the stems
Rosemary beetle, which also feeds on lavender, sage and thyme
Spread a sheet under the bush and tap the branches so the beetles and grubs fall onto it, then dispose of them. Do this every week or two from September. Hand-pick on small plants.
Whole branches turn brown and brittle in late winter or spring, starting low down, and the plant rocks loose in the soil
Root rot after the roots have sat in wet soil over winter
There is no cure once most of the plant has browned. Take cuttings from any healthy shoots and replant in a raised or gritty spot. In pots, use feet and take the saucer away from October to April.
Leaf tips and young shoots scorched brown on the windward side after a hard winter
Frost and cold, drying wind
Wait until new growth shows in late April, then trim back to live green shoots. Plant in the shelter of a wall in exposed gardens.
Blobs of white froth on the stems in May and June
Froghopper nymphs, known as cuckoo spit
Harmless to the plant. Leave it, or wash it off with a jet of water.
Leaves finely mottled with pale dots
Sage leafhopper sucking sap
Tolerate it. The damage is cosmetic and the leaves are fine to cook with.
Harvest and rotation
Harvest and storage
Snip 10 to 15 cm shoot tips year-round, taking no more than a third of the plant at once and never cutting into bare wood; oils peak just before the May flowering. A three-year bush gives several hundred grams of sprigs a year. Dry whole sprigs in a warm spot for 1 to 2 weeks and strip into jars, or freeze in bags.
Rotation and companions
No rotation needed. Keep it clear of mint, basil and anything needing rich, moist soil, and out of the drip line of trees.
Good to knowDrainage is everything; trim lightly after flowering and never cut back into bare old wood.
Growing rosemary in pots
Rosemary is a good long-term pot plant if the compost drains fast. Use a 30 to 40 cm terracotta pot with loam-based compost and a quarter by volume of grit, and stand it on feet in full sun. Water when the top few centimetres are dry in summer and hardly at all in winter. Hard tap water gradually raises the pH and yellows the young leaves, so use rainwater where you can. After three years or so the plant will have filled the pot: move it up a size in April, or tease out the roots and replant in fresh gritty compost.
Rosemary: common questions
Why is my rosemary going brown?
Wet roots are the most likely cause. Rosemary in heavy soil or a waterlogged pot loses its roots over winter and whole branches then brown from the base in spring. Browning only at the tips on one side is wind or frost scorch and will grow out. Eaten, grey-brown tips with small striped beetles point to rosemary beetle.
When should I cut back rosemary?
Trim rosemary straight after it finishes flowering, usually in June. Take a few centimetres off the green growth to keep it bushy, and always leave leaves below the cut, because bare old wood rarely reshoots. Do not trim after August. A leggy old plant is better replaced from cuttings than cut back hard.
Does rosemary survive winter outside in the UK?
Yes, upright rosemary is hardy to about minus 10°C across most of the UK, provided the soil is well drained. It is the combination of cold and wet roots that kills it. Trailing varieties are more tender and need a sheltered wall. In pots, raise the container on feet and keep it out of the worst of the rain.
Sources
Growing information on this page was checked against these references in November 2026. Feeding rates are Dr Forest label rates.