Common Name:

General Information

Retama sphaerocarpa is an upright, deciduous shrub with flexible stems and a deep root system; it usually grows around 1 - 3 metres tall but can reach around 4 metres. The leaves are very small and quickly drop from the plant. The plant remains leafless for most of the year, photosynthesis being carried out by the green stems[, ].
A multi-purpose plant, it has been widely used for a variety of purposes as a medicine and source of various materials. It is sometimes grown as an ornamental, especially in Mediterranean climates[].

Known Hazards

The plant can be toxic to grazing animals, though goats seem to be immune[].
The plant is strongly bitter and, although it is used medicinally, a strong decoction is said to produce vomiting and headaches[].

Botanical References

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Range

Mediterranean region - Portugal, Spain, Morocco, Algeria, Tunisia

Habitat

Open places, often disturbed sites, where it can form a stage in the restoration of Holm oak woodland; at elevations up to 1,400 metres[]. Sandy soils and arid areas[].

Properties

Medicinal Rating
Other Uses Rating
Habit	Shrub
Height	2.50 m
Pollinators	Bees, Insects
Cultivation Status	Ornamental, Wild

Cultivation Details

Retama sphaerocarpa is a plant of Mediterranean regions with their hot, dry summers and cool, moist winters; it can be found at elevations up to 1,400 metres. It grows mainly in areas where the average annual temperature is between 13.5 - 17.5°c and that of the coldest month can fall as low as -0.6 to 7.8°c[]. The mean annual rainfall is around 320 - 750mm, falling almost entirely in the cooler months[]. Possibly the hardiest member of the genus, it can be grown outdoors in temperate regions that are free from prolonged frosts. So long as the preceding summer has been hot enough to ripe the current season's growth, the plant is able to tolerate short periods where temperatures fall to around -10°c.[].
Requires a warm, sunny position in a very well-drained, light-textured soil and some protection from rain in the winter[]. Grows best in drier soils of low fertility[]. Established plants are very drought tolerant.
An aromatic plant[].
This species has a symbiotic relationship with certain soil bacteria; these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby[].

Edible Uses

None known

Medicinal

Whilst Retama raetam is the most commonly used medicinal species[], various studies have shown that all the species in the genus have very similar medicinal properties. They have a range of biological activities, including antibacterial, antiinflammatory, antioxidant, anti-proliferative, antiulcer, antiviral, and hepatoprotective activities[].

An infusion of the flowering stems has been used to fight liver diseases and is said to be useful in the treatment of diabetes[]. Infusions of the branches have been used to treat heart conditions and haemorrhoids[]. The leaves, stems and tender buds are used to treat colds and respiratory problems, stomach aches, to promote menstruation (and sometimes abortions), and treat conditions of the urinary tract[].
The aerial parts of the plant are a highly valued remedy in the treatment a range of bone and muscular conditions, being used in the form of poultices, ointments and plasters to treat wounds and injuries (including broken bones), sprains, dislocations, muscle aches, rheumatism, arthrosis, bursitis and tendinitis[]. They are also used to treat skin problems and as a remedy for insect and snake bites[].
The bitter-tasting stem can be chewed, or the juice of the stem applied to the tooth as a treatment for toothache and a protection against decay. A decoction of the stem, or sometimes the roots, can be used as a mouthwash[].
A decoction of the flowering stems has been used to rid the hair of lice[].

The seedpods are used as a treatment for diarrhoea[]. The seedpods and seeds have been used to treat malaria[].

The chemical composition of this plant has not been very studied, although there is a recent revision of it []. It possesses alkaloids derived from Quinolizidina (Norlupinano), which are characteristic of the Fabaceae family and of the genus Broom. The branches contain mainly sparteine and retamin, while the flowers are rich in lupanine, Retamia and Cytisina; and seeds in Cytisina []. Also present are the Esferocarpina and Anagitina []. It also contains fatty acids Ω-3 and ω-6, sterols and aliphatic alcohols, mainly in seeds, and flavonoids []. This species has been consigned as diuretic, tonic, and laxative []. The alkaloids it contains have uterotónicas activities, stimulant/depressants of the respiratory system, antipyretic and hallucinogenic, and also has flavonoids antimicrobial and others with cytotoxic activity against cervical cancer cell lines[]

Agroforestry Uses:

The plant is used in Spain as a pioneer species when reforesting native woodlands. It is usually planted in association with native trees, especially Quercus ilex and Pinus pinea. Because of its high drought resistance, and ability to fix atmospheric nitrogen, it is considered to be especially valuable in restoring semi-arid environments[].
The flowers are a good source of nectar for bees[]..

Other Uses

The branches and tender buds were thrown inside wells, cisterns and even puddles, with the intention of purifying the water. This practice was carried out only in certain months of the year and was also reinforced by adding bolus lime (quicklime) and maintaining the process for between 30 - 40 days. The observation that larvae and insects were eliminated with this custom, led it to be held as highly recommended. The branches have also been added to water that had a bad taste - the flavour is greatly improved[]

The fresh, aerial parts of the plant are said to be an effective insect repellent, especially against flies, wasps and fleas. The branches can be hung in the room, or the ground can be covered with the flowering plant. Walking on the plant increases the effect, but the effect wears off as the plant dries[].

The branches are used to make baskets, with a technique similar to that used for willows (Salix species). They are worked fresh, while they are flexible, without any previous treatment, except to clean them of all secondary stems[].

The flexible branches have been used as a tying material[].
Harvested towards the end spring, the branches are used to make brooms[].
The stems are also used as pointing implements and as divining rods for locating underground water[].

The seeds, used when freshly harvested, are strung to make necklaces[].
The dried seedpods are used as rattles[].

The plant ashes are said to make an excellent laundry whitener - the clothes are soaked in the filtered water obtained from the boiled ashes and then left in the sun for a few hours[].

A yellow dye is obtained from the stems[].

The branches have been used for making thatched roofs[].

The wood, especially the branches but also the trunk and roots, is often used for fuel, burning well and giving off a good heat. It is said to be especially useful for traditional bread ovens[]. It is a fuel of choice for traditional potters, who would often burn it whilst still green so that it produced abundant smoke - this smoke produced a gilded film upon the ceramics[]. It is sometimes used to make charcoal, but this is not considered to be of very high quality[].

Propagation

Seed - it has a hard seedcoat and benefits from scarification before sowing in order to speed up and improve germination. This can usually be done by pouring a small amount of nearly boiling water on the seeds (being careful not to cook them!) and then soaking them for 12 - 24 hours in warm water. By this time they should have imbibed moisture and swollen - if they have not, then carefully make a nick in the seedcoat (being careful not to damage the embryo) and soak for a further 12 hours before sowing.
Cuttings of half-ripe wood in a frame[].