Rosemary (Salvia rosmarinus)
10 sources cited · Verified
The short answer
- Site
- soil pH 6–7.5
- Biggest risk
- Powdery mildew
Rosemaries (Salvia rosmarinus) — perennial.
This crop carries an unusually heavy problem load: 4 diseases, 8 pests and 0 nutrient issues are documented for it, so most of the effort in growing it well goes into prevention.
Core growing advice on this page is checked against named horticultural and university-extension sources — see References.
Diseases
Pests
Quick Facts
At a Glance
Soil & Growing Conditions
Growth Stages
Harvest & Storage
Rosemary, an Evergreen Mediterranean Herb
References
-
country=INTL
-
country=INTL
-
country=USA
-
country=UK
-
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 -5C), 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.
-
Tier 1. 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.
-
country=UK
-
country=UK
-
Directly fetched and verified. 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.
-
Directly fetched and verified. 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.
10 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
What soil pH do rosemaries 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 rosemaries?
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
Almost everything on this page resolves to your own frost dates rather than the calendar — the last spring frost moves by roughly two months between zone 3 and zone 10. The USA Garden Planner works from your zone so the timing is already decided before the season starts.
Get the USA Garden Planner →Instant PDF download · Written for US growing conditions
Last verified 2026-08-29
Where To Go From Here
Take this crop from reading into a written plan for your own beds.
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.