Germination temperature
Warm soil: sow at the start of the rains or after the last frost.
Grain growing guide
Job's tears is a tall tropical grass grown for its bead-like hard-shelled seeds or, in the soft-shelled adlay form, as a grain. It needs heat and plenty of water, and its thick shell makes germination slow; this guide covers soaking, sowing and the diseases to watch for.
Warm soil: sow at the start of the rains or after the last frost.
About 5 cm (2 in).
About 1-2 weeks, depending on soil moisture.
Seed is buried; plants want full sun and tolerate light shade.
Soaking helps the hard shell take up water; hot-water treatment controls seed-borne smut.
Usually direct sown; can be raised in pots and transplanted in cool climates.
What you sow is a false fruit: the grain sits inside a hard, glossy shell (in the bead type) or a softer, striped shell (in adlay, var. ma-yuen). Sow it whole, with the shell. Smut (Ustilago coicis) is carried on seed, so field crops are treated with a fungicide or with hot water at 60-70 °C (140-158 °F) for at least 10 minutes before sowing.
Not usually needed. Water uptake through the shell is slow, but a soak is the normal way to speed it up; filing or cracking the shell risks damaging the grain.
Not needed. Job's tears is a tropical grass with no cold requirement.
Helpful, but do not overdo it. In Korean trials with adlay sown in cool spring conditions, seed given 3 days of fungicide treatment followed by a 3-day soak gave the best emergence (84-88% in pot and field tests); longer soaking increased seed rot and seedling blight. Soak in clean water and sow as soon as the shells are swollen.
No reliable cardinal temperatures are published for sowing seed. Job's tears needs high temperatures and abundant rain for growth; sow into warm soil at the start of the rainy season, or outdoors only after frost risk has passed in cooler climates. It is perennial only in frost-free climates (about USDA zones 9-11) and is grown as an annual elsewhere.
Dibble the seed about 5 cm (2 in) deep.
Reasonably fertile, moist soil; it responds well to manure. NC State lists slightly acid loam (below pH 6.0) that stays moist and occasionally wet but not soggy.
Keep the soil steadily moist. Wild plants grow along watercourses and in swampy places, and young plants need plenty of water.
Cover the seed. Full sun (6 hours or more) for strong growth.
About 1-2 weeks; drier soil makes it slower.
In the tropics sow directly: hills about 30 cm (12 in) apart in rows 40-80 cm (16-32 in) apart, at 7-15 kg seed per hectare. In short-season climates, start seed in deep pots indoors and plant out after the last frost.
Keep the crop weeded for the first 60 days or until plants are about 40 cm (16 in) tall; after that the clumps shade out weeds. Plants reach about 0.9-1.8 m (3-6 ft) in gardens.
Manure gives a good response; in traditional cropping, chemical fertilisers are rarely used.
Cause: long soaking, cold soil or seed-borne fungi. Fix: limit soaking to a few days, treat the seed, and sow into warm soil.
Cause: smut (Ustilago coicis), the most serious disease, which destroys the ovaries. Fix: hot-water or fungicide seed treatment, and do not save seed from infected plants.
Cause: leaf blight (Bipolaris coicis); rust and tar leaf spot also occur. Fix: burn or remove crop residues, rotate fields and grow resistant cultivars where available.
Cause: rats and birds, which can cause considerable losses. Fix: harvest promptly when the grain is ripe and protect small plots with netting.
Job's tears is native to the Indian subcontinent and is traditionally sown at the start of the rains. It grows from sea level to about 2000 m in the tropics. It is a short-day plant, so in India it fits the monsoon season rather than a summer sowing in long-day temperate latitudes.
A crop takes about 4-6 months (up to 8) from sowing to harvest. Cut whole plants at the base when the grain is ripe and the stalks begin to dry.
Hard-shelled beads are used for necklaces, rosaries and rattles. The soft-shelled adlay is easy to husk and is eaten as a grain; it yields 30-50% husked grain by weight.
Sun-dry after threshing. Whole (unhusked) grain keeps better than husked grain in humid weather.
Sow Job's tears with the rains for bead-like seeds or a home-grown adlay crop.
A soak helps water get through the hard shell. Korean trials found a 3-day soak after seed treatment gave the best emergence, while longer soaking increased rot. Sow once the shells swell.
About 1-2 weeks in warm soil, depending on how moist it is.
Yes, as an annual. It is perennial only in frost-free regions, so start seed indoors and plant out after the last frost.