There has been much confusion in the naming of this plant - it has often been seen as no more than a synonym of Lathyrus nervosus[]. However, according to a number of reports, Lathyrus magellanicus is a distinct species with minor botanical differences and is somewhat more cold tolerant than Lathyrus nervosus[]. It is therefore being treated as a distinct species here[].

Common Name: Lord Anson's Pea

General Information

Lathyrus magellanicus is a short-lived, herbaceous perennial, climbing plant, producing annual stems from a longer-lived rootstock; it can grow up to 50cm tall. The stems scramble over the ground and through other plants, supporting themselves by means of tendrils[, , ].
The plant is harvested from the wild for local use as a food. A very ornamental plant, it is often grown in gardens[].

Known Hazards

Although no specific records of toxicity have been found for this species, the seed and other parts of many Lathyrus species contain a toxic amino acid. It is produced in the plant at about the same time that the seed starts to develop. In small quantities the amino acid is innocuous, and the seeds of several Lathyrus species are eaten as a nutritious part of the diet. However, in larger quantities (the seed should form less than 30% of a balanced diet), it can cause a very serious disease of the nervous system known as 'lathyrism'. Symptoms appear as a paralysis of the muscles below the knees, pains in the back, followed by weakness and stiffness of the legs and progressive locomotive incoordination[, , ].

Botanical References

,

Range

S. America - southern and central Chile, southern Argentina, Bolivian Andes, Peruvian Andes

Habitat

Coastal sands, gravel and open grassland[, ].

Properties

Edibility Rating
Habit	Perennial Climber
Height	0.45 m
Pollinators	Insects
Cultivation Status	Ornamental, Wild

Cultivation Details

Lathyrus magellanicus is found at lower elevations in southern and central Chile, ascending to higher elevations of 2,400 metres or more in the tropical Andes of Peru and Bolivia. It is known to tolerate temperatures falling occasionally as low as -8°c and can also experience occasional snow cover for up to a couple of weeks per year[].
An easily grown plant, succeeding in any moderately good garden soil but preferring a position in full sun[]. Prefers a rich soil in a cool position in sun or semi-shade with plenty of moisture in the growing season[].
A very ornamental plant[]
Young plants are extremely attractive to rabbits[].
This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby[].

Edible Uses

Seed - cooked[, , ]. Some caution is advised, see the notes above on toxicity.

Medicinal

None known

Other Uses

None known

Propagation

Pre-soak the seed for 24 hours in warm water and then sow in early spring in a cold frame[]. When they are large enough to handle, prick the seedlings out into individual pots and plant them out in the summer.
If you have sufficient seed, then it can also be sown in situ in mid spring[].