Germination temperature
Germinates well across about 12-36 °C (54-97 °F) in tests; growth is best at 18-30 °C (64-86 °F).
Legume growing guide
Lablab, known in India as vaal, val, avarai or dolichos bean, is a vigorous tropical legume grown for its pods and dry beans. The key decision is the type: climbing types need a pandal and usually crop only in the cool season, while bush types are less fussy about day length.
Germinates well across about 12-36 °C (54-97 °F) in tests; growth is best at 18-30 °C (64-86 °F).
3-10 cm (1.2-4 in), deeper in light or drying soil.
No species-specific figure in our sources; quick in warm, moist soil.
Not needed for germination; day length controls flowering in many types.
Rhizobium seed treatment; no scarification needed.
Direct sow, in pits at the foot of a pandal for climbing types.
Treat the seed with Rhizobium culture: TNAU uses 600 g (three packets) per hectare, mixed with rice gruel as a sticker and dried in shade for 15-30 minutes before sowing. Inoculation matters because native soil bacteria often nodulate lablab poorly.
Not needed. Lablab has a very low proportion of hard seed.
Not needed. Lablab is a tropical crop and is damaged by frost.
Not needed, and we found no sourced benefit for it. Sow the treated seed into moist soil and irrigate.
In constant-temperature tests on tropical pasture legumes, lablab was one of the few species that germinated well at 12 °C (54 °F), and most species germinated well from 16 to 36 °C (61-97 °F). No species germinated at 8 °C (46 °F) or 44 °C (111 °F).
3-10 cm (1.2-4 in). Use the shallower end in moist, heavy soil and the deeper end in sandy or drying soil.
Tolerates soil pH 4.5-7.5 but has low salt tolerance. For climbing types, TNAU fills pits of 30 x 30 x 30 cm (12 in cube) with farmyard manure and soil.
TNAU irrigates immediately after sowing, again on the third day and then weekly. Established plants are drought tolerant but drop leaves in long dry spells.
Not required for germination.
We found no sourced germination time specific to lablab; expect seedlings within days in warm, moist soil and slower emergence in cool soil.
TNAU sows bush types on ridges 60 cm (24 in) apart with single seeds 30 cm (12 in) apart, at about 25 kg of seed per hectare.
Sow 2-3 seeds per pit with pits 2 x 3 m (6.5 x 10 ft) apart, about 5 kg of seed per hectare, and train the vines onto a pandal (overhead trellis) or strong stakes. Climbing lablab twines and needs support from the start.
Keep the young plants weeded and watered. For pandal types TNAU adds a nitrogen top dressing about 30 days after sowing.
Cause: many lablab types have a short-day flowering response. Pole types of vegetable dolichos are photosensitive and fruit in the cool rabi season. Fix: sow pole types in July-August so they crop as days shorten, or grow a photo-insensitive bush variety in other seasons.
Cause: pod borers such as Adisura atkinsoni, Helicoverpa armigera and Maruca, and bruchid beetles in storage. Fix: inspect pods regularly from flowering, remove infested pods and store only fully dried seed in airtight containers.
Cause: aphids and other sucking pests. Fix: check shoot tips weekly and act early before colonies spread to pods.
Cause: powdery mildew. Fix: improve air movement on the pandal and treat early, for example with wettable sulphur as recommended by TNAU.
Bush types are photo-insensitive and are grown in both kharif and rabi; TNAU grows bush types year round. Climbing pandal types give the higher yield but are sown in July-August for a cool-season crop.
For vegetable use, pick fully grown but still tender pods. Regular picking keeps climbing types producing over a long season.
Lablab grain contains tannins, phytate and trypsin inhibitors. Soaking and cooking reduce them, so do not eat raw beans or raw pods.
Sow white desi vaal beans for fresh pods and dry beans from one hardy plant.
Most climbing lablab types are photosensitive and flower when days shorten in the cool season. A vine sown in spring or early monsoon may grow leaves for months and then flower in autumn. For year-round cropping choose a photo-insensitive bush variety.
Climbing types do: they are twining vines, so give them a pandal or strong stakes. Bush types stand on their own.
It is recommended. Native soil bacteria often nodulate lablab poorly, and TNAU treats the seed with Rhizobium culture before sowing.