Marsh rosemary ~ Wild rosemary
(Rhododendron tomentosum)
(aka. Ledum palustre)
BREWING DETAILS

  • Parts used: Leaves and flowering tops.
  • Aroma & taste: Spicy aroma and bitter-sweet taste.
  • Brewing method: Wild rosemary is used in beer for
    it's pleasantly fresh and spicy aroma, its bitter taste and also
    its enjoyable narcotic properties. It should not be used in excess
    as it is somewhat toxic and can cause headaches. The flowering tops
    have Ledum oil, which has the strongest inebriating effects. Traditional
    beer recipes specifically call for fresh flowering tops, which indicates
    that ancient brewers knew of this increased potency and were
    specifically attempting to enhance their beers.

  • Availability: unavailable, but it's North American counterpart
    Labrador Tea is a satisfactory alternative. Available at the Gruit House.

ABOUT THE LEDUMS

Marsh rosemary has long been referred to as Ledum Palustre L.. As it has recently been discovered that Ledum Palustre L. belongs to the Rhododendron family, it's latin nomenclature has also changed to Rhododendron tomentosum Harmaja. This species actually does not occur in North America (though extends to the easternmost fringes of Asia).

Three species of the Ledum group of Rhododendron occur in North America and of these Labrador Tea (Rhododendron groenlandicum), which used to be known as Ledum groenlandicum. Labrador tea has a long history of use amongst First Nations and is now used in gruit recipes as an alternative to Marsh rosemary.

BOTANICAL DESCRIPTION

Wild rosemary, also known as Marsh rosemary, is a low shrub growing to 50 cm / 2ft tall with evergreen leaves 20-60mm / ¾-2in long and 3-15mm / ¼-½in broad. The leaves are wrinkled on top, densely hairy white to red-brown underneath, and have a leathery texture, curling at the edges. The tiny white flowers grow in hemispherical clusters and are very fragrant and sticky.

This evergreen shrub grows with irregular, woolly branches. The leaves are alternate, entire, elliptical or oblong, the upper side smooth and woolly underneath, with the edges rolled back. The large, white, five-petalled flowers grow in flattened terminal clusters.

It is in leaf all year and flowers from April to August, depending on the area. The flowers are hermaphrodite. Wild rosemary prefers acidic soils and can grow in very acid soil conditions. It can grow with various sun exposure, in full shade (deep woodland), semi-shade (light woodland) or in full sun. As one of its name suggest, it is most happy to grow in marshy, swampy areas.