How to grow Rosemary in Australia

Where to plant

Rosemary loves a hot, dry, sunny spot and well-drained, slightly alkaline soil. It tolerates poor soil and dry spells once established, but it will not survive wet feet: warm, soggy soil brings on Phytophthora root rot, the most common way rosemary dies. In heavy clay, plant on a mound or in a raised bed.

Feed little or not at all. Lean conditions give the strongest flavour.

• Melbourne, Adelaide, Perth, Canberra and Hobart: rosemary thrives. Plant in spring or autumn, and make sure the drainage is good in wet winters.
• Sydney: grows well in a sunny, well-drained spot.
• South East Queensland and the Northern Rivers: the hot, humid summers are hard on rosemary. Give it the sunniest, airiest spot, perfect drainage and a spring prune to open it up. Gardening Australia suggests a dusting of dolomite to sweeten the soil.
• North Queensland and Darwin: plant in the dry season, from May to November, in a raised bed or pot that drains fast.

Choosing a variety

• Upright types such as Salem grow to about 2 m and make a good hedge.
• Prostrate types such as Huntingdon Carpet stay low, about 25 cm, and spill over walls and pot edges.
• There are pink-flowered forms such as Pink Remembrance, and culinary selections such as Gorza with broad leaves and sturdy stems that can be used as skewers.
• Smaller-leaved types tend to cope better with drought.

How to plant

1. Most gardeners start with a potted plant or a cutting, as seed is slow and patchy and takes years to make a decent bush.
2. Choose a sunny, well-drained spot. In heavy soil, mound it up or mix in coarse sand or grit.
3. Plant at the same depth as the pot, about 60 cm apart, and water in.
4. Water during dry spells in the first year until it is established, then only in long dry periods.

Watering and feeding

Established rosemary in the ground rarely needs watering except in long hot, dry spells. Water deeply and let the soil dry out well before watering again. Overwatering kills far more rosemary than drought does.

No regular feeding is needed. On acid soils, a light dressing of lime or dolomite once or twice a year suits it.

Pruning and care through the year

• Trim lightly after flowering and again in late spring to keep the bush compact and open. In humid areas, thinning the plant before summer improves air flow and cuts disease.
• Do not cut back into old, bare wood. Rosemary rarely reshoots from it, and hard-pruned plants often fail to recover. Replace old, straggly plants with new ones from cuttings instead.
• Keep mulch, especially wet organic mulch, away from the base. Gravel mulch suits it well.

Harvesting

Cut sprigs at any time of year once the plant is growing well. Snip soft tips with secateurs rather than pulling, and spread your picking around the bush to keep it in shape.

Sprigs keep up to two weeks in the fridge, loosely wrapped. To dry them, hang small bunches in a warm, dark, airy place, then strip the leaves and store them in an airtight jar.

Growing in pots

Rosemary grows well in a pot at least 25 to 30 cm wide with drainage holes. Use a free-draining mix, or add coarse grit to a quality potting mix. Water when the top few centimetres are dry and never leave the pot standing in a saucer of water.

Using it

Rosemary is a classic with roast lamb, potatoes and vegetables, in focaccia and bread, and with beans and tomato sauces. Woody stems can be stripped and used as skewers. The flowers are also edible.

Propagation

Rosemary strikes easily from cuttings. Take 10 to 15 cm lengths of soft or half-hardened tip growth in late spring or summer, strip the lower leaves, and push them into a gritty potting mix. Keep them lightly moist in a bright spot out of hot sun and most will root within several weeks. Low stems can also be pegged to the soil to layer them.