The hundreds of plant species growing in Saudi Arabia are hardy survivors of their inhospitable environment. Perennials are found all year round, although they can become insignificant during the hot, dry summer, with fewer leaves. Some plants even withdraw underground.

Desert plants are mostly pollinated by the wind or by night-flying moths and as a consequence, the flowers are small with muted colours, at times with a strong scent. In the cooler months, desert flowers are especially spectacular, and later in the season they produce seeds and fruits in interesting colours too.

Most desert plants have been used in the past as food supplements or for medicinal purposes to treat both humans and domestic animals.

There are 54 plants of particular importance to the region; those mentioned in the Quran, the holy book of Islam, and the sayings and traditions of the Prophet Muhammad (PBUH).

ARTA

Calligonum comosum

Most of the year, the straggly calligonum bushes look barely alive. After rains, however, fresh green shoots appear on the branches. These are edible and were a much-liked vegetable green for the desert Bedouin. The arta’s tiny white flowers with their bright red stamens develop into lantern-like hairy seedpods, making the bush resemble a red flame. The plant occurs in areas of loose sand and helps to stabilise sand dunes. The thick wooden branches used to be a major source of firewood.

BARBARY FIG

Opuntia ficus-indica

Also known as the prickly pear, this species of cactus has long been a domesticated crop plant. Its yellow flowers and fleshy pink fruits are edible.

CARALLUMA

Caralluma arabica

This succulent plant can be found in extremely rocky and dry areas. It has adapted to withstand prolonged periods of drought with waxy stems preventing evaporation and spikes to reduce its attractiveness as food. Made into a tea, it was used by the Bedouin to alleviate liver ailments and treat high blood pressure.

DESERT SQUASH

Citrullus colocynthis

Any recently disturbed sandy soil makes the perfect habitat for this ground-covering vine. The long stems have beautifully shaped leaves and carry tennis ball-sized fruits, which start off green and striped and turn a brilliant yellow once ripe. Despite their marrow-like appearance, the desert squash (or 'handal' in Arabic) are unfortunately unpalatable, although the seeds are eaten by desert rodents. On the sandy plains of the Tuwayq escarpment, desert squash can produce hundreds of fruits, often strewn around a temporary water source.

DESERT THUMB

Cynomorium coccineum

This parasitic plant grows in saline soils in coastal habitats. Not having chlorophyll itself, this deep red flower has to use the roots of a neighbouring plant to get its food. Known as 'tartouth' in Arabic, it's considered a delicacy in Arab countries.

EYELASH PLANT

Blepharis edulis

This spiny plant owes its name to its flower which has one blue petal upturned like an eyelash. It grows in rocky habitats with sand. If the plant – called 'neqeil' in Arabic – is immersed in water for 10 minutes or more, a two-valve capsule opens very suddenly, throwing its seeds up to 1m away from the mother plant. This ensures its seeds are only dispersed if conditions are right, like during long spells of rain.

FIREMAKER BUSH

Leptadenia pyrotechnica

Extended areas of sand dunes are a habitat of this broom-like bush. It is seldom eaten by animals and provides shade and protection for gazelles and hares during the hottest hours of the day. When in bloom, it has clusters of tiny star-shaped flowers. It also has very long pods containing seeds attached to long silken hairs which float away on the wind. The Bedouin once used wads of these hairs as tinder, hence the name ‘firemaker’ (pyrotechnica). Called 'markh' in Arabic, it's found throughout Saudi Arabia.

GLOSSONEMA

Glossonema varians

Known as 'al'itr', 'attar' or 'kabash' in Arabic, this perennial plant grows in rocky areas, gravel plains and wadis around the Tuwayq escarpment and in the Arabian Shield. It's an attractive, leafy plant when bearing its spiky oval fruit that's edible when young.

RA

Aerva javanica

This soft, fingery-looking plant is commonly found in rocky and sandy areas across Saudi Arabia. It has tiny white flowers that appear in plume-like clusters at the ends of its stems. The ra, also known as ‘desert cotton’, grows fluffy hairs around its seeds. In days gone by, these hairs were valued as a useful fibre, used to stuff items such as saddles and cushions.

REEDS

Of the various types of reeds that can be found along wet wadis, the common reed (Phragmites australis) is one of the smallest. Reeds can be distinguished by their seed heads. A taller relation, the giant reed, also known as 'elephant grass' (Arundo donax), is found in wadis around the country and has majestic plumes which wave high against the blue skies. Although its stems can grow up to 4m, it has never been used by the local people as extensively as, for instance, bamboo has been in the Far East.

RHAZYA STRICTA

Common in sandy areas, this bush has white flowers and bean-like pods of seeds. It is toxic and not eaten by animals, but it has medicinal value. Juice from its leaves was used to treat eye infections and crushed dried seeds ingested to treat worm infestations. Smoke cleansing is believed to protect travellers.

SAND OLIVE

Dodonaea angustifolia

The entire sand olive plant has medicinal uses. Its bark extract is used to treat wounds and abdominal pain, and smoke from burning its roots is inhaled to treat headaches, bronchitis and colds. Its roots, leaves and twigs soaked in water are also used to treat colds, flu, fever, stomach trouble, measles and arthritis. A tincture from boiled roots is often drunk by women after child birth to stimulate lactation, while pounded leaves soaked in water is used against diarrhoea.

SENNA PLANT

Cassia italica

With long trailing stems and large yellow flowers, this bushy plant grows on sandy plains and thrives in recently disturbed soil. Senna, or 'ishriq' in Arabic, is used all around the world as a herbal remedy as its black curved seeds are a natural laxative.

THISTLE

Echinops mandavillei

This thistle thrives in the mountains and rocky outcrops, its flowers loved by butterflies. Its an endemic species in Saudi Arabia.