Rock sea-lavenders (Limonium spp)

KingdomPlantae
PhylumAnthophyta
ClassMagnoliopsida
OrderPlumbaginales
FamilyPlumbaginaceae
GenusLimonium (8)
SizeHeight: 4-70 cm (7)
Top facts

In Britain and Ireland Limonium britannicum, and L. procerum are classified as Lower Risk- Nationally Scarce, endemic; L. dodartiforme, L. loganicum, L. paradoxum, L. Parvum, and L. transwallianum are classified as Vulnerable, endemic, and L. recurvum is Vulnerable, endemic to Britain and Ireland (L. recurvum recurvum is endemic to Britain only). L. binervosum is not endemic to Britain and Ireland, but four subspecies are: L. b. saxonicum, L. b. anglicum, L. b. cantianum and L. b. mutatum. Furthermore, L. b. sarniense is endemic to the Channel Islands (7).

The rock sea-lavenders comprise a group of closely related, beautiful (1) and delicate (2) plants that have cushions of leaves close to the ground, from which arise branched flowering stems that may be delicate or robust, short or tall, but in all cases support numerous spikes of attractive bluish-lilac coloured flowers (1) (2). In high summer, when flowering en masse, these plants can give a striking purplish 'haze' to the places in which they grow. Almost all of the species that occur in Britain and Ireland are endemics; they are found no-where else in the world (1).

Current knowledge of the distribution of our endemic rock sea-lavenders is patchy (3). L. paradoxum, L. parvum, and L. transwallianum are all restricted to Pembrokeshire. L. britannicum and L. procerum are fairly widespread along the western coast of Britain, and L. procerum also occurs on the east coast of Ireland (7). L. dodartiforme is confined to Dorset, L. loganicum is known only from Cornwall, and populations of L. recurvum occur in Dorset, Cumberland and Wigtownshire (4). L. binervosum is not endemic to the UK; it is also known from parts of Europe (5), but four subspecies of binervosum are endemic to Britain and Ireland (7).

Rock sea-lavenders are exclusively coastal, inhabiting rocky cliffs and ledges, stabilised shingle, dune-slacks, the upper edges of saltmarshes and even sea walls (1).

In 1986 the taxonomy of the rock sea-lavenders was revised (6), nine species are now recognised, along with a large number of subspecies(2). However, the species are notoriously difficult to tell apart (2). Although there is some geographical separation of the various species and subspecies, this is by no means an accurate or reliable method of distinguishing between them (2). Indeed, there are a number of 'hot spot' areas where one can find several species or sub-species growing together (e.g. on the Carboniferous limestone of south Pembrokeshire, the cliffs of Quaternary head deposits of south Devon, and the chalk and limestone cliffs of Dorset). Rock-sea lavenders are perennial, and reproduce asexually through a process known as 'apomixis'. Flowers are produced from June to September (5).

Many populations of rock sea-lavender in the UK are not under any immediate threat. However, some may be vulnerable to trampling (4), while several dune-slack, sea-wall and cliff populations are known to have been lost, at least temporarily, as a result of dune movements, the construction of new sea defences and coastal landslips (7). Many colonies are small (which increases their vulnerability), and collecting is thought to have posed a threat to a few species (particularly L. recurvum) in the past (4).

Many populations occur within Sites of Special Scientific Interest (SSSIs), and two populations of L. parvum occur within National Nature Reserves (NNRs) (2). Together, the Botanical Society of the British Isles (BSBI) and the National Trust coordinate the conservation actions outlined in the UK Biodiversity Action Plan for Britain's endemic rock sea-lavenders (2). The BSBI have carried out an extensive mapping scheme, which will be of enormous help as it will allow areas needing further research to be prioritised and will also aid in the initiation of a monitoring programme (2).

The UK BAP Species Action Plan for rock sea-lavenders is available on-line at:
http://www.ukbap.org.uk/
See also the National Trust website:
http://www.nationaltrust.org.uk/main/ and the website of the Botanical Society of the British Isles:
http://www.bsbi.org.uk

Information authenticated by Simon Leach, English Nature. English Nature's website is available at:
http://www.english-nature.org.uk/

  1. National Biodiversity Network Species Dictionary ( 2002)
    http://www.nhm.ac.uk/nbn/
  2. Simon Leach, (2002) Pers. comm.
  3. Leach, S. (2001) Rock-sea lavender Limonium binervosum agg. Plantlife Magazine, Spring 2001.
  4. Leach, S., Pearman, D., Cordrey, L. & Jones, A. (2001) Putting rock sea-lavenders on the map. BSBI News. September. No 88.
  5. Leach, S. (2001) Rock sea-lavenders Limonium binervosum agg. Flora English Nature Newsletter. English Nature, Peterborough. Winter 2001.
  6. Wigginton, M. J. (ed) (1999) British Red Data Books. 1. Vascular Plants. 3rd Edition. JNCC, Peterborough.
  7. Stewart, A., Pearman, D. A. & Preston, C. D. (Eds). (1994) Scarce Plants in Britain. JNCC, Peterborough.
  8. Ingrouille, M. J. & Stace, C. A. (1986) The Limonium binervosum aggregate (Plumbaginaceae) in the British Isles. Botanical Journal of the Linnaean Society. 92: 177-217.