Soil: adapts to a wide range, including acidic soil, provided they are well drained
and aerated, and not saline. Optimum pH is 6–7; Lima beans (and cowpeas) often
will grow well in soils that are too acid for other beans. Mulching often improves the
growth and yield of Lima beans.
Seed rate: from 10 kg/ha for pole types in India to 130–170 kg/ha for large-seeded
bush types.
Seed spacing: Bush types: 5–20 cm between plants; 10–15 cm between rows for
large seed, 7–12 cm for small seed. Climbing types: 15–30 cm between plants, 75
cm between rows—or on hills, 120 × 120 cm, with 3–4 plants per hill. Seed size
varies from 500–1100 seeds per kg.
Depth: 2.5–5 cm in moist, heavy soil, up to 10 cm in lighter, drier soil.
GROWTH CONDITIONS
Day length: the wild types and some of the varieties from the tropics are short-day
plants, while most other types are day-neutral.
Growth period: the fastest is about 65 days, up to about 100 days, for the earliest
(ie fastest growing) bush varieties. Large-seeded white types can take 200–270 days,
producing pods for several months ie indeterminate growth habit. In the tropics lima
beans can be grown as a perennial.
Temperature: Limas need more heat than Haricots to germinate and grow well, and
growth is slow below 13C. Frost sensitive. Optimum is 16–27 C.
For planting, soil should be at least 18 C.
Rainfall: tolerates higher rainfall than Haricots, and does best in humid and sub-
humid tropics with 900–1500 mm annual rainfall or more. Can grow with only 500
mm during the growth period, but then needs some top-up irrigation and also at least
about 70% relative humidity at flowering and pod set.
Rotation: ideally Lima Beans should follow a well-manured crop such as potatoes,
though they are often grown on the same land for many years.
Altitude: the optimum is 900–1800 m in the tropics and 900–1200 m in temperate
zones.
Pests: insect attacks can be serious, though it is a tough plant and more resistant
than other legumes of the humid tropics. The plant is attacked by the same insects
that damage other Phaseolus species, and the Lima Bean Pod Borer is also a
widespread problem. The Cowpea Weevil attacks both in the field and in storage,
and the Bean Bruchid can be a serious problem in stored grain.
Diseases: like most beans, the Lima is susceptible to a number of diseases,
including:
- Root Rots—controlled with seed dressing.
- Pod Blight—seed-borne, so can be controlled by only using clean seed.
- Downy Mildew—worse in warm and humid conditions.
Spot. All can be controlled with clean seed and rotation.
- Yeast Spot—the seeds are damaged, “pitted”, without visible damage to the pod.
- Anthracnose—controlled with clean seed and crop rotation.
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- Bacterial Blights—there are three types: Common, Halo Blight and Bacterial
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PLANTING
Propagation: by seed. Mainly self-pollinated, with up to about 18% cross-
pollination.