This is a very variable species with a wide geographic range, and has at times been treated as a number of distinct species. Current thinking (2017) is that it is best treated as a single species with a number of subspecies, each with their own varieties. See below for further information[].

Common Name: Caper

General Information

Capparis spinosa is an erect or sprawling, evergreen shrub growing from 50 - 200cm tall with branches up to 4 metres long that can range from very thorny to unarmed. It grows from a deep, extensive root system[, ]. Some forms of the plant die down to the rootstock in the winter[].
The Caper plant has a very long history of human use as a food and a medicine, with evidence that it has been used since at least the Bronze Age[]. It is frequently gathered from the wild for use as a food and medicine and is also often cultivated in tropical,sub-tropical and warm temperate zones[, ]. It is used in soil stabilization projects, as a boundary marker and is also sometimes grown as an ornamental. This record contains all the uses we have recorded for the species, but this is a very variable plant and it is currently (2017) treated as comprising 6 subspecies. Two of these subspecies have a more or less temperate range, and each of these have been given a separate record in this database. See Capparis spinosa spinosa and Capparis spinosa rupestris.

Known Hazards

Caper extracts and pulps have been used in cosmetics, but there have been cases reported of contact dermatitis and sensitivity from their use[].

Botanical References

Range

Southern Europe, northern and eastern Africa, Madagascar, southwestern and central Asia, Philippines, Indonesia, New Guinea, Australia and Oceania

Habitat

On rocks, affecting the hottest localities, at elevations up to 3,600 metres in the Himalayas[]. Old walls, cliffs and rocky hillsides in the Mediterranean[].

Properties

Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Evergreen Shrub
Height	1.00 m
Pollinators	Insects
Cultivation Status	Cultivated, Wild

Cultivation Details

Capparis spinosa is a plant of drier warm temperate areas with hot summers, extending through the subtropics to tropical areas. It is found at elevations up to 3,000 metres. It grows best in areas where annual daytime temperatures are within the range 13 - 27°c, but can tolerate 10 - 31°c[]. Dormant plants can tolerate short-lived temperatures falling to between -5 and -10°c[, ]. The plant prefers a mean annual rainfall in the range 500 - 1,000mm, but tolerates 300 - 2,600mm[].
Requires a hot, well-drained dry position in full sun[, , ]. Plants can tolerate some frost so long as the ground is very well-drained. Dislikes heavy soils[]. Established plants are very tolerant of drought[]. Prefers a pH in the range 6.5 - 7.5, tolerating 6 - 8.3[].
Capers are often cultivated in tropical, sub-tropical and warm temperate zones for their aromatic flower buds, which are used as a condiment[].
Capparis spinosa is a very variable species that has at times been considered to be several distinct species. It is currently (2017) treated as one species with several subspecies. These subspecies are:-
Capparis spinosa spinosa. A very spiny, prostrate-spreading to ascending shrub with branches to 3 metres long. Found in the Mediterranean, Arabian Peninsula, Middle East to China, Nepal and India. It is commonly harvested from the wild for food and medicine and very occasionally cultivated[]. See separate entry for more information.
Capparis spinosa rupestris (Sm.) Nyman. An unarmed or sparsely armed shrub with pendulous branches 3 - 4 metres long. It is found in southern Europe, northern Africa and Anatolia. Extensively harvested from the wild for food and sometimes used as a medicine, it is often cultivated for food, especially in Spain and Italy, and is also grown as an ornamental[]. See separate entry for more information.
Capparis spinosa cartilaginea (Decne.) Maire & Weiller. A thorny, usually erect shrub growing 60 - 400cm tall. Found in northeastern and eastern Africa, through Arabia and the Levant to Pakistan and India. Often harvested from the wild as a medicine, it is also sometimes eaten[].
Capparis spinosa cordifolia (Lam.) Fici. A thorny, erect or prostrate shrub with branches usually 1 - 2 metres long. Native to tropical regions from Indonesia and the Phillipines westwards through the Pacific. It is harvested from the wild for use as a medicine and a food[].
Capparis spinosa nummularia (DC.) Fici. A thorny, prostrate-spreading shrub with branches up to 2 metres long. Native to northern Australia. The fruit is a traditional Aboriginal food[].
Capparis spinosa himalayensis (Jafri) Fici. A thorny, prostrate-spreading shrub. Native to the Himalayas of Pakistan, India and Nepal[]. See separate entry for more information.
Young caper plants can sometimes commence flowering in their first year after planting out, with full yields being achieved in 3 - 4 years[]. The plants flower on one-year old wood[].
Three year old plants can yield 1 - 3 kilos of capers a year[].
Plants can be harvested commercially for about 20 - 30 years[].
Heavy annual pruning is crucial to high production since the flower buds are produced on the current year's growth[].
The flowers open in the early morning and fade by midday[].
There are some named varieties[, ], the most commonly cultivated form tends to be the spineless Capparis spinosa inermis[].

Edible Uses

The immature flower buds are pickled and used as a flavouring in sauces, salads etc[, , , ]. A sharp, piquant flavour, they add pungency, a peculiar aroma and saltiness to foods such as pasta sauces, pizza, fish, meats and salads. The flavour may be described as being similar to that of mustard and black pepper, coming as it does mainly from mustard oil in the plant tissues[].
The young fruits and tender branch tips can also be pickled and used as a condiment[, , ]. The flower buds are harvested in the early morning and wilted before pickling them in white vinegar[].

Tender young shoots and immature small leaves - cooked as a vegetable[]. They are used like asparagus[, ].

Mature and semi-mature fruits are occasionally eaten as a cooked vegetable[].

Ash from the burned roots has been used as a source of salt[].

Medicinal

Capers have a long history of medicinal use[]. They are said to reduce flatulence and to be antirheumatic[].
In Ayurvedic medicine they are said to be hepatic stimulants and protectors, improving liver function - and these uses have been confirmed by modern research[].
Capers have reported uses for arteriosclerosis, as diuretics, kidney disinfectants, vermifuges and tonics. Infusions and decoctions from caper root bark have been traditionally used for dropsy, anaemia, arthritis and gout[].
Capers contain considerable amounts of the anti-oxidant bioflavonoid rutin[].

The root-bark is analgesic, anthelmintic, antihaemorrhoidal, aperient, deobstruent, depurative, diuretic, emmenagogue, expectorant, tonic and vasoconstrictor[]. It is used internally in the treatment of gastrointestinal infections, diarrhoea, gout and rheumatism[, ].
Externally, it is used to treat skin conditions, capillary weakness and easy bruising[].
The bark is harvested in the autumn and dried for later use[].

The stem bark is bitter and diuretic[]. If taken before meals it will increase the appetite[].

The unopened flower buds are laxative[]. They are used internally in the treatment of coughs, and externally to treat eye infections[]. The buds are a rich source of compounds known as aldose-reductose inhibitors - it has been shown that these compounds are effective in preventing the formation of cataracts[].
The buds are harvested before the flowers open and can be pickled for later use - when prepared correctly they are said to ease stomach pain[].

A decoction of the plant is used to treat vaginal thrush[, ].

The leaves are bruised and applied as a poultice in the treatment of gout[].

Aqueous, ethanol and butanol crude extracts of the aerial parts of the plant were tested for antimicrobial activity. The butanol extract was the most effective, followed by the ethanol extract. The aqueous extract had low activity. The butanol extract at 2000 μg/disc had a very good antibacterial activity against both gram‐positive and gram‐negative bacteria as well as moderate to good antifungal activity against Candida albicans and Aspergillus flavus[].

Agroforestry Uses:

The plant has a far-ranging root system and, especially the prostrate forms, can be used as a soil stabilizer in dry regions[].

Other Uses

An extract of the root is used as a cosmetic and is particularly useful in treating rose-coloured rashes and capillary weaknesses[]. See notes above regarding known hazards.
An extract of the buds and berries is used as an ingredient in commercial cosmetic preparations for skin conditioners[].

Propagation

Caper seeds are miniscule and seedlings are very slow growing. The fresh seed germinates quickly, although germination rates are usually quite low[]. Dried seed becomes dormant and notably difficult to germinate - pre-soak for 24 hours in warm water at around 40°c which is then allowed to cool. Then wrap them in a moist cloth, place them in a sealed glass jar and kept in the refrigerator for 2 - 3 months. After refrigeration, soak the seeds again in warm water overnight. Sow the seeds about 1cm deep in a loose well drained soil medium in a sunny position in a greenhouse[]. Prick out the seedlings into individual pots of well-drained soil when they are large enough to handle. Grow on the young plants for at least their first winter in a greenhouse and plant out in late spring or early summer.
Cuttings of half-ripe wood, mid-summer in a sandy medium in a cold frame[]. Use stems from the basal portions, greater than 1cm diameter and 8cm long with 6 - 10 buds. Use a loose, well drained media with bottom heat. A 70% rooting percentage would be considered good[]