A perennial herb of coastal habitats, growing on the banks of ditches containing brackish water, in brackish pastures, and in the transition zone between the upper saltmarsh and freshwater habitats. It is intolerant of grazing and cutting. It also occurs as a garden escape. Lowland.
A. officinalis has declined throughout most of its British range, due to drainage and development in the coastal zone. Much of the loss occurred before 1930, but it has continued since then, particularly in East Anglia.
Eurosiberian Temperate element; widely naturalised outside its native range.
Light (Ellenberg): 7
Moisture (Ellenberg): 7
Reaction (Ellenberg): 8
Nitrogen (Ellenberg): 4
Salt Tolerance (Ellenberg): 2
January Mean Temperature (Celsius): 4.4
July Mean Temperature (Celsius): 16.4
Annual Precipitation (mm): 774
Height (cm): 120
Perennation - primary
Life Form - primary
Clonality - primary
Count of 10km squares in Great Britain: 125
Count of 10km squares in Ireland: 0
Count of 10km squares in the Channel Isles: 2
Atlas Change Index: -0.29
Scarce Atlas Account
Althaea officinalis L.
A. officinalis is locally frequent in the coastal zone, growing on the banks of ditches with brackish water or where the upper parts of saltmarsh give way to freshwater habitats. It is particularly common by ditches in grazing marshes which have been converted to arable land, as it is notably intolerant of grazing and cutting. It can form a dominant sward in brackish pastures from which stock have been removed. It is a shade-tolerant species, found under Quercus robur by the Solent estuary where ancient woodland borders saltmarsh. The distribution of A. officinalis is strictly lowland, and at coastal sites it grows mainly on alluvial soils. It is also recorded as an escape from cultivation away from the coast.
A. officinalis is a perennial, flowering in the late summer and reproducing by seeds.
This species has declined through most of its British range, partly due to drainage and partly due to the development of the coastal zone for industry and housing. The decline was first noted in the last century (Hanbury & Marshall 1899) and still continues except where sites survive on waterlogged soils, near the sea, but protected from stock.
A. officinalis reaches its northern limit in Europe in Britain, Denmark and central Russia, also occurring in north Africa and west Asia, and as a rare introduction in North America.
The past use of A. officinalis for the production of sweetmeat and its ornamental appearance are responsible for its introduction well outside its native range.
J. O. Mountford