Rosemary is very easy to grow. Just give your rosemary plants the three things below and they should thrive.
1 - Decent drainage
Rosemaries need a very well-drained site.
To test this dig a hole 25cm square by about 25cm deep. Pour in about 2 litres of water.
If the water has gone after 15 minutes the drainage is OK.
2 - Proper pH
Rosemary prefers a slightly chalky soil with a pH of 6.0 to 7.5.
Use a soil test kit to determine your soil's pH.
You can add lime to raise the soil pH but if very acidic grow your rosemary in pots.
3 - Sun, sun, sun
Coming from the Mediterranean rosemary is a real sun-worshipper!
It can tolerate a little shade but will flower less.
Rosemary can be grown in pots, preferably unglazed terracotta, on a sunny terrace or patio.
Ways of growing rosemary
Rosemary is often just thought of as a herb for cooking. However, rosemary is also a useful garden shrub.
To discover more about the conventional, and some unusual, ways to grow rosemary just click on the images below or scroll down the page.
Growing
in the ground
Growing
in pots
Hedges
and topiary
Rosemary
bonsai
Growing rosemary in the ground
Rosemary is an excellent coastal plant, great for gravel gardens, drought-resistant plantings and low-maintenance gardens. Rosemary can be used formally as clipped hedges or topiary and informally in cottage and herb gardens. Prostrate and creeping forms will drape over walls.
Rosemary is a signature plant for Californian- or Mediterranean-styled gardens and is an essential member of any herb garden.
Pros
- Plant will grow larger
- Better flavour
- Easy to care for
Cons
- Plant may grow too large
- More risk from wet and frost
Cultivation
Rosemary is an easy-to-grow shrub. The best time to plant rosemaries in the ground is from about mid-April until the end of September. It responds well to regular pruning. To maintain vigour prune the flowering shoots back after flowering. Rosemaries can flower in late winter and again in late summer.
If you harvest a lot of rosemary then do give the bush a feed every so often. Once established feed at the start of the growing season. At the end of the summer a feed of high-potash (rose or tomato) fertiliser will help harden-off tender new growth, which can really help the plant through the winter.
Renovation
When planted in the ground rosemary can live for many years. We are often asked how to restore an old rosemary that has grown leggy. Unfortunately, it is virtually impossible to renovate an old gnarled rosemary as it rarely regenerates from old wood.
Propagation
Rosemary is easily propagated from semi-ripe cuttings, layering or from seed.
If you have a named variety it must be vegetatively propagated to ensure it "comes true".
Growing rosemary in pots
When grown in pots, rosemary can be easily placed anywhere sunny. Formally-clipped rosemaries in pots either side of steps or a bushy rosemary by the gate. The choice is yours.
Pros
- Can control growing conditions
- Can move plants indoors in winter
- Pots make a feature
Cons
- More feeding and re-potting needed
- Plant may be water stressed and
- Pests can be more of a problem
Potting Mix
We recommend a mix of four parts of high-quality potting compost with one part of coarse limestone grit thoroughly mixed. For all our rosemaries we use the excellent Fertile Fibre peat-free and certified organic composts. Whatever compost you use the resulting mix should fall apart if squeezed rather than form a ball. It is vital that the container's drainage holes are not blocked. It is a fallacy that putting crocks in the bottom of a pot will improve the drainage of the soil above.
Pruning
To keep your rosemary nice and bushy prune it after flowering and every so often during the growing season. Regular pinching out of sprigs for cooking will have the same effect!
Feeding
After about eight weeks your rosemary will use up all the nutrients in the compost. To keep it growing well it will need a regular feed of a balanced fertiliser.
Repotting
Eventually, all pot-grown plants need repotting. You only need to go up to a slightly bigger size with each repotting - big enough to add a little more potting mix to the bottom and sides.
Alternatively, start over again. We find that rosemary will look good for about five years in pots.
Hedges and topiary
Rosemary can be used for formal and informal hedges. Rosemary clips well and can be shaped into topiary forms such ball on stem (standard) or domes or pyramids... ...whatever takes your fancy!
Rosemary hedges
Topiary at Marqueyssac
Choice of rosemary
Rosemary hedges are usually between 60cm and 120cm in height. This permits a wide choice of rosemary cultivars and most of the flower colours. The most commonly offered hedging rosemary is the Common Rosemary (Rosmarinus officinalis). We like 'Miss Jessopp's Upright', which makes a dense hedge and tastes good, too!
We do not regard rosemary as being suitable for replacing very dwarf box hedges (30cm or less)
Clipping
To keep your rosemary hedge or topiary nice and bushy it should be clipped after flowering in spring and again towards the end of the summer. Odd straggly bits can be trimmed throughout the year.
Feeding
As with all regularly-clipped shrubs feeding is vital to ensure the plant has enough nutrients to remain healthy. A general fertiliser in spring and a high potash fertiliser in the autumn should keep your rosemary in prime condition. Feed too much and it will need trimming more frequently!
Buying from us
We are increasing the production of our best hedging rosemaries. If you have a project that might need a rosemary hedge please contact us to discuss your requirements.
Update: Hedging, supplied at 5 plants to the metre, is often available from our online shop.
Bonsai
With its rough and often twisted stems and needle-like leaves it's hardly surprising that rosemary is used in bonsai.
Rosemary for Bonsai
Although any cultivar of rosemary could form the basis for a bonsai perhaps the most promising varieties may be those that are of a naturally dwarf, or low growing, habit. In addition, we usually have some older plants with restricted root growth that would make an excellent starter for your bonsai project.
We do not sell finished bonsai rosemary yet but if you are interested in using any of our rosemary cultivars for your own bonsai please do contact us.