How to Grow Cluster Beans UK

Quick Facts

Factor	Value
Soil pH	7 - 8
Germination temp	30°C
Time to harvest	45-100 days
Soil texture	Well-drained alluvial and sandy-loam soils; tolerates salinity; waterlogging not tolerated
Drainage	Free-draining
Lifecycle	Frost-tender annual of hot, dry climates.

Soil & Growing Conditions

Water: Low; 500-800 mm, best seed production below 800 mm

Soil pH range

7 8

Span reflects genuine variation between the cited authorities, not a single agreed figure.

Harvest & Storage

When to pick: TNAU: harvesting starts at 45 days in early varieties and at 100 days in late varieties. Pods are picked young for eating, while they snap cleanly.

Cluster bean through the season

The vegetable

Young pods picked while they still snap. This is how guar is eaten across India, long before the seed matures.

Establishing

TNAU gives spacing of 45 x 15 cm at 10 kg of seed per hectare. Germination is best near 30°C.

In flower

Flowers are carried on an upright spike and pass through pink to light purple.

The flower spike

Pods form in the tight clusters that give the crop its English name.

The seed

Hard, flinty, about 5 mm. Milled for guar gum, a thickener PROSEA rates 5-8 times stronger than starch.

Picking

TNAU: harvesting starts at 45 days in early varieties and at 100 days in late ones.

In leaf

Bushy and erect, 20-100 cm in improved cultivars and up to 3 m in landraces.

Its own conditions

Well-drained alluvial and sandy-loam soils at pH 7.0-8.0. Waterlogging is not tolerated.

Left to mature

Pods darken as seed fills. Seed maturity comes 110-160 days after sowing.

Always cooked

Green pods carry 40-70 mg hydrocyanic acid per 100 g, removed by thorough boiling. Never eat them raw.

What the research guides add

Cluster bean is the same plant as guar, a heat-loving summer legume, so the question for most gardens is whether the soil gets warm enough.

• A coarse, upright, bushy, drought-resistant summer annual, 2 to 9 feet tall, native to India, where it is grown for green fodder and for pods used as food. (UF/IFAS Extension)
• It is sensitive to cold, so grow it in the warm season; a soil temperature of 70°F is necessary for germination. (UF/IFAS Extension)
• It is a short-day plant, setting denser clusters in winter than in summer in Puerto Rico, and it grows better when irrigated even though it is fairly drought resistant. (UF/IFAS Extension)
• Where killing frosts are a danger, Florida advises a spring or a fall crop. Its culture (spacing and method of seeding) is similar to soybean. (UF/IFAS Extension)
• Arizona describes guar as very well adapted to arid and semiarid climates with high temperature and plenty of sunshine, and growing best in well-drained soil of coarse to medium texture. (University of Arizona SBAR)
• Guar is susceptible to waterlogging, so heavy clay soils are not recommended; where drainage is poor, raised beds protect the roots from root pathogens. (University of Arizona SBAR)

Sources for this section

• University of Florida IFAS Extension: HS608 Guar, Cyamopsis tetragonoloba
• University of Arizona, Sustainable Bioeconomy for Arid Regions: Guar

Section researched and checked on 25 October 2026 by the SoilCommander Editorial Team. How we check facts: editorial policy.

References

1. Plant Resources of South-East Asia (PROSEA) - Cyamopsis tetragonoloba (PROSEA)
2. Tamil Nadu Agricultural University (TNAU Agritech Portal) - Horticulture :: Vegetables :: Clusterbeans

2 independent sources are cited for this crop. Where they disagree - soil pH is the clearest case - every figure is preserved rather than averaged into false precision.