Bugle weed is the common name given to at least two low-growing flowering ground cover plants which are members of the Ajuga family, Lycopus europaens and Lycopus virginicus. Ajugas are part of the Lamiaceae, the same grouping to which plants of the mint family belong. Other names by which bugle weed is known include water bugle, sweet bugle, Virginian water horehound, and gypsy weed. Bugle weeds usually have shining, ovalshaped leaves that are reminiscent of spinach leaves in appearance and have glandular dots on their underside. This foliage grows thickly along the surface of a spreading transverse root. Bugle weed blooms in spring, typically producing flowers of a startling cobalt blue. Some species, however, have pink or white flowers. Bugle weed flowers are tubular and lipped in appearance, growing in whorls along the erect spikes that rise from the dense foliage.
There are different varieties of bugle weed with varying characteristics:
- Ajuga genevensis, or Geneva bugle weed, is one of the taller varieties. It has very dense, dark green leaves, which can grow to 4–5 in (10–12 cm) in length, and produce spikes 6–12 in (15–30 cm) high with either pink or blue flowers in clusters along the spike.
- Ajuga pyramidalis, or upright bugle weed, is a bushy, slower-growing plant with very shiny leaves that are slightly puckered. This variety also has bright blue flowers.
- Ajuga Reptans is the most common type of bugle weed. It is smaller, with 4–10 in (10–20 cm) spikes, and leaves 2–3 in (5–7.5 cm) in length. Its flowers are the same cobalt blue, and leaves may be either dark green or bronze-colored. There are several highly attractive sub-types in the A. reptans grouping. A. reptans alba has white flowers; Atropurpurea has bronze leaves; burgundy glow bugle weed has three-toned white, green and pink foliage; and several others are combinations of these.
Bugle weed grows in either sun or shade, in well-drained, fairly rich soil. It establishes itself rather quickly and spreads via underground roots. It can become very invasive, and generally provides a mat of dense ground cover that does not permit the growth of weeds or other plants. It can be propagated by dividing the plants.
It is believed that bugle weed is native to the Northern Hemisphere, worldwide. Species of bugle weed are found in Europe, Asia, and North America. Like other members of the Laminaceae or mint family, bugle weed has a mild, pleasant, mint-like aroma when it is freshly picked. It contains flavone glycosides, volatile oils, and tannins.
Beside its horticultural use as an attractive spreading ground cover in rock gardens and other types of gardens, bugle weed is useful medicinally for several different purposes. It is an astringent, and is considered to have sedative qualities as well. It can calm anxiety symptoms, including heart palpitations. It is a valued cough suppressant. In old herbal remedy books such as Thayer's Fluid and Solid Extracts, and even in the more recent A Modern Herbal, the authors state that in addition to cough suppression, bugle weed is also useful for healing tuberculosis and stopping bleeding from the lungs. It has long been recognized in Western herbal medicine as a cardiac tonic and can actually slow a rapid heart rate and improve the functioning of a weak heart by increasing the strength of the heartbeat. Because of its diuretic properties, bugle weed is useful in removing excess fluid from the body and thus improving circulation. It has been shown to inhibit the body's metabolism of iodine, and is helpful for this reason in treating hyperthyroidism. Poultices containing bugle weed leaves in combination with other herbs have been found to speed the healing of bruised areas. Lastly, bugle weed is useful in weaning babies as it helps to suppress the production of breast milk.
All parts of the bugle weed that grow above ground are used in herbal medicine. It is collected in early spring before the flower buds open. The entire plant is dried and pulverized, and used as a decoction or tea. The tea is made by pouring a cup of boiling water over one teaspoonful of dried bugle weed, and allowing this mixture to steep for 10–15 minutes. This tea may be taken three times a day. A bugle weed tincture is also available. Poultices are made from the leaves, stems and flower buds, steeped in boiling hot water. Clean white cloth is soaked
Bugle weed should not be used internally if a person has a thyroid condition unless they have consulted a physician or health care practitioner. Because of bugle weed's influence on thyroid function and its ability to reduce secretions (including breast milk), it should be used only for short periods and prescribed by a trained practitioner.
In addition, plants in the mint family, which includes bugle weed, are high in methyl salicylate. This compound causes allergies in some people.
The Complete German Commission E Monographs includes reports of uncommon cases of long-term high-dosage therapy with bugle weed preparations resulting in enlargement of the thyroid gland. When this herb is used in the treatment of hyperthyroidism, its sudden stoppage can result in an increase in the symptoms.
Bugle weed preparations may interfere with the use of radioactive isotopes used in some diagnostic procedures.
Blumenthal, Mark. The Complete German E Monographs, Therapeutic Guide to Herbal Medicine, 1998.
Grieve, M., and C. F. Leyel. A Modern Herbal: The Medical, Culinary, Cosmetic and Economic Properties, Cultivation and Folklore of Herbs, Grasses, Fungi, Shrubs and Trees With All of Their Modern Scientific Uses. New York: Barnes and Noble Publishing, 1992.
Hoffman, David, and Linda Quayle. The Complete Illustrated Herbal: A Safe and Practical Guide to Making and Using Herbal Remedies. New York: Barnes and Noble Publishing, 1999.