Lathyrus japonicus aka Beach Pea

Lathyrus japonicus has the common names beach pea and sea pea. Other names for it are circumpolar pea and ytbysen arfor. It belongs to Fabaceae, the pea family. The RHS accepts Lathyrus japonicus as its correct scientific name. These common names and the scientific name refer to the species here. The name matters when checking which facts apply to this plant. The draft also names a taxon that must stay distinct.

Kew lists this species as a climbing perennial. Its stems climb, and it lives for more than one year. That is what the term perennial means here. The sources for this species give no height at full growth. They give no spread at full growth, either. So they do not show how much space it may take. Beyond the fact that its stems climb, they give no stem details. They give no details of its leaves, flowers or fruit.

Its native range spans cold and temperate parts of the north. Kew gives its range as the Subarctic to China and Japan. The range also runs from the Aleutian Islands into the United States. There, it reaches parts of the west and north. The RHS confirms that it is native to Britain and Ireland. These places form the native range given in the draft. The draft gives no further detail on its range within them.

The sources for this species do not set out its garden care needs. Nor do they state the limits of its hardiness. Its native range does not fill those gaps in the evidence. The draft gives no species-level account of pests or diseases. It also gives no such account of food uses or toxicity. These gaps leave its care needs and safety unconfirmed here. A lack of food-use or toxicity notes does not establish safety.

The detailed notes on growing and food use concern another named taxon. That name is Lathyrus japonicus maritimus, not the species name used here. Those notes cannot establish how to care for this species. They cannot establish its safety or its food uses, either. Keep that limit in mind when reading the names. The draft does not support moving those details from one taxon to the other.