Rosemary
A sun-loving shrub whose scent evokes the Mediterranean, rosemary has needle-like leaves that can be picked all year round. Fresh or dried leaves can be used to flavour meat, soups and many other dishes, while sprigs steeped in olive oil give it a distinctive flavour. Tea made by infusing chopped leaves in boiling water is said to help digestion.
Jobs to do now
- Protect plants in pots and young plants in the ground
Month by month
Sow
Rosemary is best started in the spring from ready-grown plants. Plant in a sunny, sheltered position in well-drained soil – plants hate wet roots in winter. Alternatively grow in 30-60cm containers filled with soil-based or multi-purpose compost.
Grow
Plants are fairly drought-tolerant, but water regularly during dry summers, especially if plants are grown in containers. Feed plants in containers with a balanced fertiliser after they have finished flowering.
It can be a good idea to give your plants some protection in hard winters and in particularly cold areas. Protect container-grown plants by raising onto pot feet. Apply a thick mulch around plants in the ground and cover the branches with sheets of horticultural fleece.
To keep plants compact, cut back stems after the blooms start to fade or plants will become leggy.
Common problems
Frost damage
Late frosts can damage growth, leading to it dying or being distorted.
Remedy
Remove any damaged growth and protect the bed with a double layer of horticultural fleece if frost is forecast.
Scale insects
Small yellow hemispherical scales appear on the leaf underside and along the midrib. They suck sap and secrete honeydew which encourages sooty mould.
Remedy
Use biological controls in the greenhouse.
Rosemary beetle
Both the small oval beetle with metallic green and purple stripes, and its greyish white larvae are a problem. The pest can be found in great numbers on plants, where it will quickly strip stems of leaves.
Remedy
Check plants regularly and pick beetles off by hand.
Harvesting
Rosemary is evergreen, so can be harvested all year round, but the soft new growth in summer has the best flavour. Snip off shoots as required, aiming to keep an attractive shape to the plant.
The leaves can be used fresh or dried for later use.
To dry rosemary, hang up sprigs in a warm, dark, well-ventilated place. When fully dried, strip off the leaves and store in an air-tight jar.
Recommended Varieties
Common
Salvia rosmarinus
The excellent basic garden and culinary rosemary with a vigorous upright habit, dense green foliage & full flavour. It can grow to 120cm but given a regular monthly topping in summer it will remain full of upright spires ideal for cutting. Flowering times are irregular with light blue flowers.
McConnell's Blue AGM
One of the many prostrate forms, ‘McConnels’ has a regular mounding & flowing habit with arching branches carrying full foliage & a starry scattering of speckled dark blue flowers.
Miss Jessop's Upright AGM
Salvia rosmarinus 'Miss Jessopp's Upright'
A very upright, strong growing variety with thick stems and a dense covering of needle- like leaves. Flowers are light blue. An architectural and tall rosemary with very good flavour.
Pink
Rosemary flower colours range over all shades of blue, or even white or pink depending on variety. ‘Roseus’ is the original dark pink Rosemary with deep green leaves. Height 90cm.
Trailing
Ideally grown over walls, down steep slopes, from tall containers or chimney pots, or in hanging baskets. It has multi- branching downward stems, mid-blue flowers and good flavour.
Get involved
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