Distinguishing Feature : A small plant with a drooping pink bell-shaped flower growing in a very wet bog, wetter than Bog Myrtle likes.
Resemblance to: Cranberry, in that Cranberry is also very short and has the same pink coloured petals (if not the shape) and your feet will be getting wet when you examine it closely for it occupies much the same kind of terrain; wet boggy ground!
Bog Rosemary flowers twice in the season, the first flowering late April to June; the second flowering September to October.
Being a member of the Heather and Crowberry Family, it has bell-shaped flowers very similar in shape, if not colour, to
This plant is smaller that what I expected, only slightly higher than the star mosses with which it was growing. Any slight disturbance to the flower invariably resulted in the petals falling off immediately, as many had already done without my assistance.
The leaves are dark-green, narrow lanceolate, out-rolled at the edges and pointed at the tips, with prominent translucent veins showing through in the sunlight.
The distribution of Bog Rosemary is confined to the middle latitudes of North-West UK and is the County Flower of Cardiganshire, Kircudbrightshire and Tyrone.
Bog Rosemary is a short woody undershrub of very wet places usually growing amidst
Bog Rosemary contains glycosides called
Grayanotoxins, which are the toxic compounds present also in other members of the Heather Family including Rhododendrons and American Laurels (Kalmia), especially the leaves. They are also present in the Genera Chamaedaphne, Gaultheria, Ledum, Leucotho, Lyonia, Pernettya and Pieris, some of which are non-native to the UK.
Grayanotoxins bind to the sodium channels in nerve cell membranes, blocking the passage of sodium ions and thus preventing the cells from returning to normality, leaving them permanently excited. When ingested, it lowers the blood pressure which can lead to dizziness, vomiting, diarrhoea, tremors, heart disturbances and may cause breathing problems. Convulsions coma and death may result if sufficient quantities are consumed. Cattle and sheep are more at risk, for they are more likely to eat the leaves or flowers of Rhododendrons or
Azaleas such as Yellow Azalea. Just a few leaves are enough to kill a human.
Honey gathered by bees from these plants is also toxic, so bee colonies should not be placed near Rhododendrons or Azaleas, especially since they themselves can also be poisoned by Grayanotoxins. The Turkish people produce a bitter and potentially toxic honey called 'Pontic Honey', containing nectar and pollen from Rhododendron Ponticum. This results in an alarming intoxicated state and total incapacitation, lasting up to a day, but is rarely fatal.
Grayanotoxins were previously known by the names
Sphagnum Moss in shallow water on acid soils. Thus habitat includes bogs and wet peaty heathland.