🌿 Understory GuidePlant FinderGuild Builder

beach pea

Lathyrus japonicus · Fabaceae

beach pea (Lathyrus japonicus)
Photo: (c) Dmitry Kulakov, some rights reserved (CC BY) · CC BY · via iNaturalist

beach pea (Lathyrus japonicus) is a perennial vine in the Fabaceae family. It is native to North America. USDA records it as hardy in zone 3 and warmer, down to about -33°F.

At a glance

Typevine Derived
Lifecycleperennial USDA
Native statusnative USDA
Mature height1.5 ft USDA
Lightpart-shade USDA
Water needmedium USDA
Growth ratemoderate USDA
Soil pH6–7.5 USDA
BloomMarch–April USDA
Flower colorPurple USDA
Hardiness zones3 and warmer USDA
Guild layerclimber Derived
Nursery availabilityContracting Only USDA

USDA quoted from the USDA PLANTS database · Derived computed by a fixed rule from those columns. No value on this page is estimated.

Growing conditions

It grows in partial shade. USDA rates it as having moderate water needs. Its drought tolerance is rated medium. It will not tolerate waterlogged soil — USDA rates its anaerobic tolerance as none. It is recorded on soils from pH 6 to 7.5 — a broad range that spans acidic through mildly alkaline ground. Its cold limit is zone 3.

Size and growth

At maturity it reaches about 1.5 ft, making it about knee height. It grows at a moderate rate.

Bloom period

USDA records a bloom period of March through April. Flowers are purple.

A flowering date, not a pollinator rating.

Foliage, flower and season

Summer foliage is dark green, medium in texture. Its flowers are conspicuous. Its fruit or seed heads are conspicuous, extending interest past flowering. Its active growth period is spring and summer. USDA rates its lifespan as short, so plan on replacing or resowing it rather than treating it as permanent structure.

What the site needs to provide

USDA records it across sites receiving 30 to 60 inches of annual precipitation. It needs at least 190 frost-free days to finish its season. It roots to at least 16 inches. Fertility requirement: low — no feeding needed on ordinary garden soil.

Propagating it

Propagate it from seed and sprigs. USDA records no cold-stratification requirement, so seed should germinate without a chilling period. Its seed spreads at a slow rate. It spreads vegetatively at a moderate rate.

Resilience and wildlife

Browsing animals rate it barely palatable — the sourced basis for calling it deer-resistant. Its fire tolerance is rated high. Its growth form is recorded as single crown.

Role in a guild

Climber. In a layered planting this is it uses other plants or structures for vertical support rather than standing on its own. The layer is derived by a fixed rule from growth habit and mature height.

Build a guild around beach pea →

Tags

deciduousdrought-tolerantsalt-tolerantsandy-soildeer-resistantspreadingnativenitrogen-fixerclimber

Related plants

Others in Lathyrus

Similar role and hardiness

Where this data comes from

Every value on this page comes from the USDA PLANTS database record for symbol LAJA, or is computed from those values by a fixed rule. Nothing here is estimated or model-generated. Where USDA publishes no value, this page omits the claim rather than filling the gap.

Read our full data sources and methodology.

Find more plants for your zone with the Plant Finder.