Erect, sprawling or prostrate shrub to 2 m tall, bark brown. Leaves crowded, stalkless, leathery, linear, 1-3 cm long, 1-7 mm wide; margins rolled under, only the midrib visible beneath; lower surface with a dense covering of hair. Flower clusters 2-7 cm long, terminating axillary shoots and occasionally the main shoot. Flowers 10-20, the bracts 1-2 mm long, ovate, green; stalks 2-5 mm long. Calyx bell-shaped, green or yellow-green, 5 mm long, covered with short, branched hairs; upper lip entire, lower lip 2-lobed. Flower tube 4 mm long, upper lip 7 mm long, deeply 2-lobed, lower lip 3-lobed, the central lobe to 6 mm long, 10 mm wide, concave, marked with dots and 2 parallel nectar guides in a deeper colour, the lobes sometimes slightly rolled at the edges, reducing their apparent size, grey, blue, pink or white, and sometimes changing slightly as the flower ages; summer to autumn. Stamens 2, curving forward with the style and protruding about 11mm.

Mediterranean (near coastal)

Naturalised locally in WA and SA.

Extensively cultivated.

Rosemary has been in cultivation for centuries and several wild forms have been brought into cultivation. It is easy to grow and tolerant of drought. Plants sold as Rosemary, without further qualification, are erect, branched shrubs to 2 m tall with leaves about 2-3 mm wide and greyish (slate blue) flowers. Other growth habits, largely genetically controlled, develop because young plants send up several vertical shoots which may stay erect and form a fastigiate shrub useful for hedging, or bend under their own weight after they reach a height of up to 1 m, in which case they form a sprawling shrub which self-layers. This type of growth is rather misleadingly termed 'semi-prostrate'. Some plants produce shoots so weak that they ascend for only a few centimetres and the result is a prostrate shrub. These plants are particularly suited to growing over rocks or walls. In the truly fastigiate shrubs, the axillary shoots are slow to develop beyond the 4-leaf stage and flowering is consequently delayed.

This widespread, variable species has been divided by botanists into several varieties which correspond to geographic distribution, leaf width and growth habit, and several forms based on flower colour and growth habit. Some of these botanical names have persisted as cultivar names. The variations in growth habit and flower colour have been given simple descriptive names in Australia, e.g. 'prostrate', 'semiprostrate', 'white', 'pink', 'blue'. Particular selections have been sold under promotional names, e.g. Blue Lagoon. A number of plants are available as named cultivars which originated in Britain or the USA. Some of these are correctly named; there is doubt about others. There are dozens of English and American cultivars and it is expected that more of these will be imported either as ornamentals or for oil production.

The fragrant shoots have been used as a culinary herb, air freshener and medicinal herb. Once considered a cure for poor memory, thus becoming a symbol of remembrance; it was once distributed at weddings and funerals and is now worn on ANZAC Day.

Calyx covered with star-shaped hairs but lacking the simple unbranched hairs that are characteristic of the other species, which are probably not grown in Australia. Plants labelled R. lavandulaceus seem always to be prostrate selections of R. officinalis.

Rosemaries now available in Victoria are listed under the Cultivars tab. The confusion over the names of the semi-prostrate, blue-flowered Corsican plants cannot be sorted out until a good collection of rosemaries is available. In addition to the cultivars are the following promotional names in the trade.

Beneden Blue A promotional name for a plant apparently int. as 'Frimley Blue', an English cultivar of unknown origin with narrow, olive-green leaves and deep (China) blue flowers. Beneden Blue has particularly narrow leaves (1 mm) and differs from 'Benenden Blue'. ['Primley Blue' is probably the correct name for the plant sold as 'Frimley Blue']

Blue Lagoon A long-standing promotional name for a semi-prostrate Rosemary with narrow leaves (1-2 mm) and deep (China) blue flowers. It is the most commonly grown ornamental Rosemary in Vic. Its origins lie in the blueflowered Corsican rosemaries grouped under var. angustifolius. It may be the same as 'Collingwood Ingram'.

Gallipoli is a promotional name for a selection of Rosemary growing wild at Gallipoli in Turkey. It has the growth habit and slate blue flowers of wild plants.

Grey Lady A promotional name for an erect, grey-flowered plant, perhaps 'Miss Jessupp's Upright'.

A similar species to Rosmarinus officinalis is R. eriocalyx, which occurs in Spain and neighbouring North Africa; it has calyces with both simple and star-shaped hairs.

Source: Lumley, P. (2002). Rosmarinus. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 4. Flowering plants. Dicotyledons. Part 3. The identification of garden and cultivated plants. University of New South Wales Press.