Common Name: Red Leg

General Information

Persicaria maculosa is an erect to procumbent, annual plant with stems that can be branched or simple[ it can grow from 20 - 120cm tall[, ].
The plant is harvested from the wild for local use as a food, medicine and source of materials.
Persicaria maculosa is an annual plant that can be very competitive with crop plants, particularly in moist areas, and has an ability to spread rapidly once introduced to an area. The economic impact of the plant in agricultural production is sufficient for various governments to declare this weed as a noxious pest, and it is also listed as invasive in many areas, especially the Ameriicas[].

Known Hazards

Although no specific mention has been made for this species, there have been reports that some members of this genus can cause photosensitivity in susceptible people.
Many species also contain oxalic acid (the distinctive lemony flavour of sorrel) - whilst not toxic this substance can bind up other minerals making them unavailable to the body and leading to mineral deficiency. Having said that, a number of common foods such as sorrel and rhubarb contain oxalic acid and the leaves of most members of this genus are nutritious and beneficial to eat in moderate quantities. Cooking the leaves will reduce their content of oxalic acid. People with a tendency to rheumatism, arthritis, gout, kidney stones or hyperacidity should take especial caution if including this plant in their diet since it can aggravate their condition[].

Botanical References

, ,

Range

Widespread in the Temperate regions of the northern hemisphere, including Britain.

Habitat

Damp shady places[]. A common weed of cultivated land, avoiding shade[]. Weedy, moist semiwaste to cultivated area[]. Streamsides, wet areas, field margins; at elevations from 100 - 1,800 metres[].

Properties

Weed Potential	Yes
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Annual
Height	0.60 m
Pollinators	Self
Self-fertile	Yes
Cultivation Status	Wild

Cultivation Details

Persicaria maculosa is a very cold-hardy plant, being able to tolerate temperatures down to around -25°c when fully dormant. It is also a very adaptable plant and can be found through much of the temperate zone, extending into the subtropics and also at moderate to high elevations in the tropics[].
Succeeds in an ordinary garden soil[] but prefers a moisture retentive not too fertile soil in sun or part shade[]. Repays generous treatment[]. Plants are often found in wet moist soils in the wild, but they also tolerate periods of dryness. They do not tolerate highly acidic soils[].
Plants seem to be immune to the predations of rabbits[].

Edible Uses

Leaves and young shoots - raw or cooked[, , , ]. They contain about 1.9% fat, 5.4% pectin, 3.2% sugars, 27.6% cellulose, 1% tannin[].

We have no specific information for this species, but the seed of most, if not all, members of the genus is edible both raw and cooked, and is potentially a good source of amino acids. Unfortunately the seed is also usually rather small and fiddly to utilize[].

Medicinal

The leaves are astringent, diuretic, rubefacient and vermifuge[, , , , ]. An infusion has been used as a treatment for gravel and stomach pains[].
The crushed leaves have been used as a rub to alleviate poison ivy rash[].

A decoction of the plant, mixed with flour, has been used as a poultice to help relieve pain[]. A decoction of the plant has been used as a foot and leg soak in the treatment of rheumatism[].

Other Uses

A yellow dye is obtained from the plant when alum is used as a mordant[].

Propagation

Seed - sow spring in situ. Seeds are dormant when they are shed from the plant, and require a cold, moist period in order to break that dormancy[]. Length of initial seed dormancy varies widely on individual plants and between populations. Seeds normally germinate in the springtime, and those that do not germinate the first season enter secondary dormancy[]