Lemna minor
L.
Duckweed, Common duckweed
no rights reserved, uploaded by Philipp
(c) Patrick Hacker, some rights reserved (CC BY), uploaded by Patrick Hacker
(c) Attila Oláh, some rights reserved (CC BY), uploaded by Attila Oláh
What to Eat
Edible parts: Leaves
Occasionally used as a vegetable. No further details are given but we have found the flavour to be less than desirable.
Known Hazards
Where to Find It
A cosmopolitan plant, found in most regions of the world, including Britain, absent from Tropics.
TEMPERATE ASIA: Yemen, Afghanistan, Iran, Iraq, Israel, Jordan, Lebanon, Syria, Turkey, Azerbaijan, Georgia, Kazakhstan, Kyrgyzstan, Tajikistan, Uzbekistan, Russian Federation (Primorye, Kamcatskij kraj, Sakhalin), China (Xizang Zizhiqu) TROPICAL ASIA: India (north), Nepal, Pakistan (Punjab) NORTHERN AMERICA: Canada (Québec, Ontario, Newfoundland and Labrador, Saskatchewan, British Columbia), United States (Connecticut, Indiana, Maine, Massachusetts, Michigan, New Hampshire, New Jersey, New York, Ohio, Pennsylvania, Rhode Island, Vermont, West Virginia, Illinois, Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, Oklahoma, South Dakota, Wisconsin, Idaho, Montana, Oregon, Washington, Alabama, Arkansas, Delaware, Florida, Kentucky, Louisiana, Maryland, North Carolina, Tennessee, Virginia, District of Columbia, New Mexico, Arizona, California, Utah) EUROPE: Denmark, Finland, United Kingdom, Ireland, Norway, Sweden, Austria, Belgium, Switzerland, Czech Republic, Germany, Hungary, Liechtenstein, Luxembourg, Poland, Slovakia, Russian Federation (European part), Belarus, Estonia, Lithuania, Latvia, Moldova, Russian Federation (Kalmykija, Respublika, Astrakhan, Saratov, Volgogradskaja oblast), Ukraine (incl. Krym), Albania, Bulgaria, Bosnia and Herzegovina, Greece, Croatia, Italy (incl. Sardinia, Sicily), Montenegro, Romania, Serbia, Slovenia, Spain (incl. Baleares), France (incl. Corsica), Portugal AFRICA: Spain (Canarias), Portugal (Madeira Islands), Algeria, Egypt, Libya, Morocco, Tunisia, Ethiopia, Sudan, Kenya, Uganda, Democratic Republic of the Congo, Rwanda, Mozambique, South Africa (Cape Province, Kwa. Zulu-Natal, Transvaal)
How to Identify
Lemna minor is a PERENNIAL. See above for USDA hardiness. It is hardy to UK zone 4 and is not frost tender. It is in flower from June to July. The species is monoecious (individual flowers are either male or female, but both sexes can be found on the same plant). It is noted for attracting wildlife. Suitable pH: neutral and basic (mildly alkaline) soils. It cannot grow in the shade. It can grow in water.
How to Grow
Requires a sunny position in still water that is rich in nitrates and lime. Duckweed can be a troublesome pond weed though it is easily controlled by simply scooping it out. This scooped out material makes an excellent addition to the compost heap. The growing plant is a good food source for fish and birds, as well as providing cover for creatures in the pond. Although it is towards the limit of its climatic range in Britain, it often flowers here if growing in a sheltered sunny position. It over-winters in temperate areas by means of resting buds which sink to the bottom of the pond in the late autumn and rise again in the spring.
Propagation: Seed - we have no information on this species but, since it spreads so rapidly by division, it really needs no extra help once it is in a pond.
Medicinal Uses
Alterative Antirheumatic Antiscorbutic Astringent Depurative Diuretic Febrifuge Homeopathy Ophthalmic Sedative Skin. The whole plant is alterative, antipruritic, antiscorbutic, astringent, depurative, diuretic, febrifuge and soporific. It is used in the treatment of colds, measles, oedema and difficulty in urination. It is applied externally in the treatment of skin diseases and is used as a wash for ophthalmia. The plant is used in homeopathy, but the report gives no more details.
Other Uses
Repellent. The dried plant repels mosquitoes.
