Lathyrus japonicus
Willd.
Beach Pea, Smallflower beach pea
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(c) Meghan Pierce, some rights reserved (CC BY-NC), uploaded by Meghan Pierce
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(c) Gabe, some rights reserved (CC BY-NC), uploaded by Gabe
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(c) Travis Cameron, some rights reserved (CC BY-NC), uploaded by Travis Cameron
Description
Lathyrus japonicus is a PERENNIAL growing to 0.6 m (2ft). See above for USDA hardiness. It is hardy to UK zone 3. It is in flower from May to August, and the seeds ripen from August to October. The species is hermaphrodite (has both male and female organs) and is pollinated by Bees, Lepidoptera (Moths & Butterflies). It can fix Nitrogen. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It cannot grow in the shade. It prefers dry or moist soil. The plant can tolerate maritime exposure.
Edible Uses
Young plant - raw or cooked. An excellent sustenance.
Known Hazards
The seed contains a toxic amino-acid which, in large quantities, can cause a very serious disease of the nervous system known as 'lathyrism'. The seed is said to be perfectly safe and very nutritious in small quantities, but should not comprise more than 30% of the diet.
Distribution
W. and N. Europe, E. Asia - China. N. America.
Where It Grows
TEMPERATE ASIA: Russian Federation-Western Siberia (Western Siberia (north)), Russian Federation-Eastern Siberia (Eastern Siberia (north)), Russian Federation-Far East (Far East), China (Hebei Sheng, Liaoning Sheng, Shandong Sheng, Zhejiang Sheng), Korea, Japan NORTHERN AMERICA: Canada (Northwest Territories, Nova Scotia, Ontario, Prince Edward Island, New Brunswick, Newfoundland and Labrador, Manitoba, British Columbia), Greenland (south), United States (Alaska, Connecticut (south), Indiana (northwest), Maine, Massachusetts (east), Michigan, New Hampshire (south), New Jersey, New York, Ohio (north), Pennsylvania (northwest), Rhode Island, Vermont (north), Illinois (north), Minnesota (north), Wisconsin (east & north), Oregon, Washington, California (northwest)) SOUTHERN AMERICA: Argentina (w. Patagonia) EUROPE: Denmark, Finland, United Kingdom, Ireland, Iceland, Norway, Sweden, Germany (north), Poland (north), Russian Federation-European part (European part (north)), Spain (north-central), France (north)
Cultivation
An easily grown plant, succeeding in any moderately good garden soil. It prefers a deep moist well-drained soil in a cool position. Prefers a position in full sun, growing well on hot sunny banks. The seed remains viable for 4 - 5 years in sea water. 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.
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. Division in spring. It may not transplant well so care should be taken.
