Sword bean (tua phra) Canavalia gladiata
Sword bean (tua phra) (Canavalia gladiata) is an evergreen perennial vegetable in the Fabaceae family, native to Tropical Asia (known only in cultivation; probably derived from wild C. lineata or C. virosa). It grows 3–10 m (10–33 ft) tall and 1–2 m (3.3–6.6 ft) wide, wants full sun and moderate water, and is hardy to about 5 °C (41 °F). Space plants about 1 m (3.3 ft) apart.
Plan Sword bean (tua phra) in your garden →
Free. Draw your beds, then watch it grow through the year in 2D and 3D.
Sword bean (tua phra) at a glance
| Type | Perennial vegetable, evergreen |
|---|---|
| Family | Fabaceae |
| Mature height | 3–10 m (10–33 ft) |
| Mature spread | 1–2 m (3.3–6.6 ft) |
| Spacing | 1 m (3.3 ft) centre to centre |
| Sun | Full sun, at least 6 h of direct sun a day |
| Water | Moderate; drought tolerance moderate, waterlogging tolerance none |
| Soil pH | 5–7 |
| Cold hardiness | About 5 °C (41 °F) once established (roughly USDA zone 11) |
| Heat stress | Likely above about 38 °C (100 °F) |
| Flowering | about 11–17 weeks after planting, for 9–17 weeks |
| Wind tolerance | Low |
| Pollinator value | Moderate |
| Edible | Yes: young pods (cooked), young seeds (cooked) |
| Native to | Tropical Asia (known only in cultivation; probably derived from wild C. lineata or C. virosa) |
| Common in gardens of | 🇹🇭 Thailand, 🇮🇳 India, 🇯🇵 Japan, 🇨🇳 China, 🇮🇩 Indonesia |
Is Sword bean (tua phra) toxic?
- People: moderately toxic
- Cats: mildly toxic
- Dogs: mildly toxic
- Parts: mature seeds, raw pods
Mature seeds contain canavanine and lectins and must be soaked and boiled thoroughly; eat young pods cooked.
If a child or pet may have eaten part of a plant, call a poison centre or vet straight away.
Companion planting: what to grow with Sword bean (tua phra)
Good neighbours
- good With Sweet corn: "Three sisters": climbing beans use corn as a support and fix nitrogen; the benefit to the corn is modest but real in low-input soils. Evidence C
Keep apart or take care
- caution With Alliums (onion family): Onions, garlic and leeks are said to stunt beans and peas (allium root exudates may reduce nodulation). Traditional companion-planting advice; controlled trials are few, so treat it as a soft preference. Evidence D
- caution With Alliums (onion family): Beans and peas are traditionally kept away from onions, garlic and leeks. Traditional companion-planting advice; controlled trials are few, so treat it as a soft preference. Evidence D
- caution With Fennel: Fennel is reported to suppress beans and peas growing next to it. Evidence C
Questions about Sword bean (tua phra)
- How far apart should I plant Sword bean (tua phra)?
- About 1 m (3.3 ft) apart, centre to centre. A mature plant spreads 1–2 m (3.3–6.6 ft).
- Does Sword bean (tua phra) need full sun?
- Full sun: at least 6 hours of direct sun a day.
- How much water does Sword bean (tua phra) need?
- Moderate water. Drought tolerance is moderate and waterlogging tolerance none.
- How cold-hardy is Sword bean (tua phra)?
- It tolerates about 5 °C (41 °F) once established, roughly USDA zone 11.
- When does Sword bean (tua phra) flower?
- About 11–17 weeks after planting, for 9–17 weeks.
- Is Sword bean (tua phra) poisonous to cats and dogs?
- For cats it is mildly toxic; for dogs mildly toxic; for people moderately toxic. Mature seeds contain canavanine and lectins and must be soaked and boiled thoroughly; eat young pods cooked.
- What grows well with Sword bean (tua phra)?
- "Three sisters": climbing beans use corn as a support and fix nitrogen; the benefit to the corn is modest but real in low-input soils.
Sources and evidence
Evidence grade B (B: extension service or peer-reviewed).
- Plants of the World Online (taxonomy, native range), Royal Botanic Gardens, Kew
- PROSEA: Plant Resources of South-East Asia, PROSEA Foundation, Bogor
- EcoCrop crop environmental requirements, FAO
Notes and assumptions
- Tropical: needs warm nights all year; in a frosty climate grow it under glass or as a summer container plant.
- A vigorous twining bean with huge sword-shaped pods; in Japan young pods are pickled for fukujinzuke.
Reference values for planning, not horticultural, veterinary or medical advice. Varieties, soils and local climates differ: check with a local nursery or extension service.
Related plants
- Bush bean Phaseolus vulgaris
- Garden pea Pisum sativum
- Sweet pea Lathyrus odoratus
- Runner bean Phaseolus coccineus
- Broad bean (fava) Vicia faba
- Lima bean Phaseolus lunatus
- Cowpea (black-eyed pea) Vigna unguiculata
- Yardlong bean Vigna unguiculata subsp. sesquipedalis