Wild asparagus (Asparagus prostratus)
|Size||Stems: up to 70 cm (exceptionally 130 cm) (1)|
Classified as Vulnerable in Great Britain (2).
This plant is our native asparagus species (3) and is endemic to Western Europe (1). Recent evidence indicates that wild asparagus is a separate species to garden asparagus (Asparagus officinalis spp. officinalis) and not a subspecies (Asparagus officinalis ssp. prostratus) as previously thought (1). The stems grow prostrately (4) and have needle-like leaves, which reach 16 (exceptionally 24) mm long. The flowers are small and green (5), and produce bright red berries (2).
Once recorded from 34 sites on the coasts of southern and south-west England and Wales; it is now known from 28 sites. In England it occurs in Cornwall and in a single site in Dorset. In Wales it is known from Pembrokeshire and the Gower coast (5). It has also been recorded in Sussex and Anglesey (5). Elsewhere, the species occurs on the coasts of Spain, France, the Channel Islands, the Netherlands, Belgium, Ireland and Germany (1). It is rare and threatened in Belgium and Ireland, and may be extinct in Germany, but is locally abundant in Spain and parts of France (1).
This plant mainly occurs within a few hundred metres of the sea in open, grassy vegetation, more rarely in gorse scrub (1). It occurs on sea cliffs, occasionally on sand dunes and is rarely found on shingle (1).
A long-lived perennial, the stems are produced from ‘rhizomes’ that allow the plant to slowly spread by vegetative reproduction (2). New stems are produced each year in April and May, and flower from May and June. The plants are ‘dioecious’, with male and female flowers occuring on different plants (1). Insects pollinate the flowers, and the berries, which are dispersed by birds and small mammals, begin to turn red from July to October (2).
Reported threats to this species include the trampling of cliff-top areas, soil erosion, and a widespread decline in grazing and management, leading to a decline in habitat suitability (2) resulting from the subsequent growth of grasses (6). Furthermore, a decrease in the genetic viability of some populations is likely (2). Feeding by the asparagus beetle (Crioceris asparagi) has a significant effect at some sites, and cross-pollination is an important factor in limiting fruit-set in some populations with only a few scattered plants (7).
Wild asparagus is a UK Biodiversity Action Plan priority species; the Species Action Plan includes targets to enhance the population size at all known sites, with the aims of doubling the wild population at sites with less than 10 plants (around 9 sites) by 2008 and creating an additional two populations at former sites. Surveys in 1999-2001 showed that of the 28 populations, single plants occur in 4 sites, 5 sites have fewer than 10 plants, and only three sites have more than 100 plants (5). Most of the areas where wild asparagus occurs are sites of Special Scientific Interest (SSSIs) (6). Furthermore, seeds have been collected and plants that have been raised
Visit the website of the National Trust:
For more on this species see the UK BAP Species Action Plan available at:
Information authenticated by The National Trust:
http://www.nationaltrust.org.uk/main/ and by Tim Rich of the National Museums and Galleries of Wales.
- Endemic: a species or taxonomic group that is only found in one particular country or geographic area.
- Perennial: plants that live for at least three seasons; after an initial period they produce flowers once a year.
- Rhizome: rhizomes are thickened, branching, creeping storage stems. Although most rhizomes grow laterally just along or slightly below the soil's surface, some grow several inches deep. Roots grow from the underside of the rhizome, and during the growing season new growth sprouts from buds along the top. A familiar rhizome is the ginger used in cooking.
- Subspecies: a different race of a species, which is geographically separated from other populations of that species.
- Vegetative reproduction: type of asexual reproduction (reproduction without recombination of genetic material) that results in the propagation of plants using only the vegetative tissues such as leaves or stems. The resulting plant is genetically identical to the original plant. A well-known example of this is the reproduction of strawberry plants from 'runners'.
- Kay, Q.O.N., Davies, E.W. and Rich, T.C.G. (2001) Taxonomy of the western European endemic Asparagus prostratus (A. officinalis subsp. prostratus) (Asparagaceae). Botanical Journal of the Linnean Society, 137: 127 - 137.
- Wigginton, M.J. (1999) British Red Data Books 1; Vascular Plants. 3rd Edition. JNCC, Peterborough.
- Grigson, G. (1996) The Englishman’s Flora. Helicon Publishing Ltd., Oxford.
- Mabey, R. (1996) Flora Britannica. Sinclair-Stevenson, London.
- Rich, T.C.G., Bennallick, I.J., Cordrey, L., Kay, Q.O.N., Lockton, A.J. and Rich, L.K. (2002) Distribution and populations sizes of Asparagus prostatus Durhort, wild asparagus, in Britain. Watsonia, 24: 183 - 192.
UK BAP Species Action Plan (March, 2002)
- Rich, T. (2002) Pers. comm.