How to Grow Rosemary UK
On this page
In the UK, rosemary goes in the ground early March to early April.
Timing is the decision that matters most in the UK: sowing early March, and that same window applies across all 4 regions covered here.
The short answer
- Plant
- Early March to early April
- Site
- soil pH 6–7.5
- Biggest risk
- Powdery mildew
Core growing advice on this page is checked against named horticultural sources — see References.
Rosemary (Salvia rosmarinus)
11 sources cited · Verified
When to Plant Rosemary in the UK
When to plant rosemary in the UK: in Southern England, sow early March to early April. Find your area in the table below.
Quick Facts
At a Glance
Soil & Growing Conditions
Growth Stages
Harvest & Storage
Diseases
Pests
Rosemary, an Evergreen Mediterranean Herb
Plan your Rosemary planting
When to sow and plant Rosemary depends on your own frost dates. Check the UK vegetable planting calendar. To work out where it fits in your beds, sketch your plot in the free Garden Layout Planner.
Growing Rosemary in another region
Sowing dates, frost timing and local advice differ by country. Use the guide for where you garden.
References
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Woody evergreen perennial shrub, hardy USDA zones 8a-10b, typically 4-5ft tall and 3-4ft wide though cultivars vary widely; space 3-6ft apart according to the cultivar. Full sun (6+ hours). Wants light, slightly acidic, dry to medium, WELL-DRAINED soil; tolerates most soils except clay and has a low tolerance for wet, humid conditions. Highly drought tolerant. Propagate by stem cuttings, layering or division -- seed germinates slowly, so vegetative propagation is usually more practical. Once flowering is over it can be pruned hard to thicken the foliage. Leaves are picked through the season for cooking, teas and potpourri. Pests and diseases: aphids, mealybugs, whiteflies, spider mites, powdery mildew, root rot and botrytis -- but OVERWATERING is the common cause of decline or death.
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RHS explicitly does not recommend pesticide use against aphids; recommends tolerance, manual squashing, and encouraging/purchasing natural predators (ladybirds, hoverflies, lacewings, parasitoid wasps, earwigs) as biological control, especially under glass.
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RHS factsheet on glasshouse red spider mite (two-spotted spider mite), naming tomato and strawberry among the host plants affected under glass or in a polytunnel.
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RHS explicitly distinguishes yellow sticky traps as a monitoring tool rather than a standalone control method, and notes traps also catch non-target parasitoid wasps -- a genuine trade-off between two control methods, preserved rather than simplified. No specific pesticide/insecticidal soap product is named on this page (RHS links out to a general pesticides statement instead), so none is recorded here.
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An easy to grow, aromatic, evergreen shrub with attractive foliage and flowers, bushy habit ranging from prostrate to upright, used as hedging or ground cover depending on variety. Native to the Mediterranean, not native to GB/Ireland. Hardiness H4 (hardy through most of the UK, -10 to -5°C), needing protection from excess winter wet and hard frosts in colder locations. Full sun, south- or west-facing, sheltered. Soil: chalk, loam or sand; well-drained; neutral, acidic or alkaline pH, not too acidic. Height and spread 1.5-2.5m. Time to maturity 5-10 years. Propagated by seed in a cold frame in spring or semi-ripe cuttings in summer. Pests: rosemary beetle, cuckoo spit, sage leafhopper, tortrix moth caterpillars, scale insects. Diseases: honey fungus (rarely), powdery mildews, verticillium wilt, foot and root rots. Aromatic foliage used for culinary purposes. Skin allergen -- wear gloves when handling.
11 independent sources are cited for this crop. Where they disagree - soil pH is the clearest case - every figure is preserved rather than averaged into false precision.
Frequently Asked Questions
When should I sow rosemary in the UK?
In Southern England, from early March. In Scotland, wait until early March. Treat these as a guide rather than a fixed date — the governing rule is to sow only once frost risk has passed and temperatures are reliably warm enough.
When do I sow rosemary?
Sow early March to early April, at around 21°C for germination.
What soil pH does rosemary need?
A pH of about 6–7.5. That span reflects genuine variation between the authorities we cite rather than a single agreed figure — the References section lists each source's exact range.
What problems affect rosemary?
Our data links 4 diseases and 8 pests to this crop. See the sections above for each one and how to manage it.
Plan next season before the problems start
Most of the advice on this page comes down to timing and spacing — sowing at the right moment, rotating beds, and giving plants enough airflow. The UK Garden Planner lays your plot out month by month so those decisions are already made before the season starts.
Get the UK Garden Planner →Instant PDF download · Written for UK growing conditions
How this guide is put together
The growing data on this page — sowing windows, pests, diseases, soil and site requirements — comes from named horticultural sources, listed in References below, checked against RHS and Met Office guidance. An automated pipeline assembles that verified data into the page you're reading: it selects which facts to lead with and builds the surrounding prose and layout. It does not invent a date, a source or a number — where a verified value for a field isn't available, the page leaves it out rather than guessing. A person reviews and publishes each page; nothing goes live unverified.
Related Problem Guides
Last verified 2026-09-02
Plan Rosemaries by month
The months this guide gives for sowing or planting, each with the full list of jobs for that month in the UK:
More from the same group (herbs & aromatics):
Growing advice for your part of the UK
Timing and conditions change a lot inside one country. These guides cover frost dates and growing seasons region by region.
Where To Go From Here
Take this crop from reading into a written plan for your own beds.
Keep going
Plan the next step
Use the printable SoilCommander planner for your region to turn this guide into sowing dates, bed layouts and weekly garden tasks.