Yard Long Bean

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Yard Long Bean Links

• Purdue University, Indiana
• International Legume Database and Information Service
• Thailand 

Species: Vigna unguiculata (L.) Walp. cv. group Sesquipedalis

Family: Cucurbitaceae

Crop status: Established

Varieties

Javanese prefer a cultivar called 'Javan Kacang panjang' which grows to 25 cm (Vinning 1995). There are dwarf (bush) and climbing types. Climbing types take longer to reach production, but then produce for longer (Poffley 1997). A hybrid between yard long bean and cowpea has become popular in the Philippines (Grubben 1994). See Seedquest for a list of seed companies.

Figure 1: Production volume and value of yard long bean in the Northern Territory 1995/96 (from Lim 1998).

Agronomic trials

Observation work has been done at NT DPIF and at Murwillumbah.

Production

Grown commercially in NSW, NT, Qld and Vic (Lee 1995).

Climate: Suited to regions with warm summers, even if not very long (Larkcom 1991).

Temperature: The plant prefers 25-35ºC, remaining above 15ºC at night (Lim 1998). It grows in cooler climates but yields are lower, and requires a sunny position that is sheltered from wind (Larkcom 1991).

Photoperiod: Most varieties are short-day plants that do not flower until after the summer solstice (Larkcom 1991). It performs best under full sunlight (Grubben 1994).

pH: The plant tolerates acid soils (Larkcom 1991) and prefers a range of 5.5 - 7.5 (Lim 1998).

Soil type: Yard long bean grows in poor soil but yields are affected (Larkcom 1991).

Soil preparation: It is preferable to grow on raised beds or ridges. Two rows can be planted on beds 1.2-1.5 m wide (Lim 1998). Soil should be worked to a fine even seedbed (Poffley 1997).

Sowing: Sow at 2 cm deep directly into rows. Plant into damp soil and withhold water for 3-4 days to prevent seed rot (Poffley 1997). Germination will take 3-5 days in moist soil above 22ºC (Grubben 1994). A legume root inoculant is recommended (Larkcom 1991) though should not be necessary on land previously used for legumes (Grubben 1994).

Plant density: Growers in the Northern Territory plant at 40 cm between plants and 60-90 cm between rows (Lim 1998). Dwarf beans can be planted much more densely (Poffley 1997). Seed weight varies from 150-250 g/1000 seeds (Grubben 1994).

Trellising: Grown on 2 m high fence trellises. Climbers must be trained up the vertical supports (Lim 1998).

Nutrition: The crop benefits from a monthly side dressing of 50:50 urea and muriate of potash mix at 5 g/m (Poffley 1997).

Water: Yard long bean requires plenty of water (Lim 1998) at regular intervals, generally 2-3 times / week (Poffley 1997). It can be grown with very low rainfall but yields are affected (Larkcom 1991). The plant can adapt to waterlogging that is brief (4 days) or extends through to harvest with only a small reduction in yield. However, plants that have had time to adapt to waterlogging conditions (eg; 2 weeks) will be severely stressed if those conditions are discontinued (Nawata et al. 1991).

Pollination: Flowering commences 5 weeks after sowing. Cross pollination by insects is generally low, but higher in humid climates. Pollination should be restricted on highly fertile soils to prevent low pod set and disease (Grubben 1994).

Harvest: First harvest 8-10 weeks after sowing (Poffley 1997), then 2-3 harvests / week during the 6-8 week season (Lim 1998). Beans are ready when they reach full length (30-50 cm) but before the seeds begin to swell. Cut pods with a sharp knife to minimise plant damage, thus maximising harvest (Poffley 1997). Picking should be meticulous as leftover pods become hard and the seeds swell, exhausting the plant (Grubben 1994). Seed that was harvested at 16 days after pollination gave maximum quality in Thailand (Chuntarachurd et al. 1984).

Yield: 15 t/ha is considered satisfactory but 30 t/ha is possible. Average 1988 yields in Thailand and Indonesia were 7.2 and 2.9 t/ha respectively. Greenhouses in the Netherlands have produced marketable yields of 8 kg/m2 (80 t/ha) (Grubben 1994) though 3 kg/m2 is more common (Heij 1989, Mol 1984).

Postharvest

Temperature: Temperatures below 4ºC cause pitting and browning (Poffley 1997). When transferred back to 15ºC, this chilling injury results in complete deterioration of the affected tissue (Zong et al. 1992).

Shelf life: Storage at 10ºC gives a minimum shelf life of two weeks (Melinda Gosbee 1999, pers. comm.). Observed quality defects include rapid dehydration, yellowing and seed development (Zong et al. 1992).

Relative humidity: The plant is less susceptible to loss of weight by transpiration than most other vegetables (Grubben 1994).

Pests and diseases

Bean fly is the main pest around Darwin, causing small yellow spots on the leaves. Seedlings are especially vulnerable. Spray plants at emergence, 3 days after and 7 days thereafter with dimethoate (Rogor®), also used against aphids. Red spider mite is a problem in hot, dry weather, producing a speckled silvery appearance on leaves. Spray with dicofol (Kelthane®) (Poffley 1997). The plant is quite resistant to fungal attack (Grubben 1994). Potential viruses are listed at Plant viruses online (Brunt et al. 1996). See Hawaiian pests & diseases.

Figure 2: High and low prices of yard long bean at Flemington Markets during 1997 (blue) and the first half of 1998 (red) (no data for 1996), recorded on a half monthly basis (Flemington Market Reporting Service, NSW Agriculture).

Domestic market

Northern Territory producers receive between $2.00 and $3.50/kg (Lim 1998).

Export markets

(click here for exchange rates).

Development potential was rated as high for fresh exports to Malaysia and Indonesia (Vinning 1995).

Indonesia produced 368 410 tons in 1989 from 251 905 ha (Lim 1998). The country imported 46 322 tons in 1992. Imports were mainly dried bean, which has a much lower tariff (10% compared to 30% for fresh). Import prices were AUS$1.90 in 1994 (Vinning 1995).

Malaysian production rose steeply in the 1980's, reaching 79 000 tons in 1990, and imports are minimal (Vinning 1995). If yields have remained at 1986 levels of 30 t/ha (Lim 1998), then Malaysia will have produced 150 000 t in 1994.

Thailand production was around 90 000 t/year in the 1980's (Vinning 1995) and rose to 132 000 t in 1994 (Lim 1998).

References

Brunt, A.A., Crabtree, K., Dallwitz, M.J., Gibbs, A.J., Watson, L. and Zurcher, E.J. (eds.) (1996 onwards). `Plant Viruses Online: Descriptions and Lists from the VIDE Database. Version: 16th January 1997.'

Chuntarachurd, T., Sagwansupyakorn, C., Subhadrabandhu, S. and Sripleng, A. (1984). Seed yield and seed quality of yard long bean (Vigna unguiculata (L.) Walp. sub sp. sesquipedalis (L.) Verdc.) at different harvesting stages. [Thai]. The Kasetsart Journal 18(3): 123-127.

Grubben, G. J. H. (1994). Vigna unguiculata (L.) Walp. cv. group Sesquipedalis. In: Plant Resources of South-East Asia: Vegetables. (Ed.: Siemonsma, J. S. and K. Piluek). Wageningen, The Netherlands, Pudoc Scientific Publishers 274-278.

Heij, G. (1989). Yard-long bean. A yield of three kilogrammes of yard-long beans per m2 is possible in the autumn culture. [Dutch]. Groenten en Fruit 44(52): 35.

Larkcom, J. (1991). Oriental vegetables: the complete guide for garden and kitchen. London, John Murray 232 pp.

Lee, B. (1995). Audit of the Australian Asian vegetables industry. RIRDC Research Paper No. 95/13. Canberra, Rural Industries Research and Development Corporation 97 pp.

Lim, T. K. (1998). Loofahs, gourds, melons and snake beans. The New Rural Industries. Ed.: K. W. Hyde. Canberra, Rural Industries Research and Development Corporation: 212-218.

Mol, C. (1984). Temperature and plant relationship with yard-long bean. [Dutch]. Groenten en Fruit 39(47): 32-34.

Nawata, E., Yoshinaga, S. and Shigenaga, S. (1991). Effects of waterlogging duration on the growth and yield of yard long bean (Vigna sinensis var. sesquipedalis). Scientia Horticulturae 48: 3-4.

Poffley, M. (1997). Growing snake beans in the top end. Darwin, Primary Industry and Fisheries, Northern Territory of Australia 2 pp.

Vinning, G. (1995). Market Compendium of Asian Vegetables. RIRDC Research Paper No. 95/12. Canberra, Rural Industries Research and Development Corporation 386 pp.

Zong, R. J., Cantwell, M., Morris, L. and Rubatzky, V. (1992). Postharvest studies on four fruit-type Chinese vegetables. Acta Horticulturae 318: 345-354.