Growing Food: A Guide to Food Production

• Virus Diseases—there are several, such as Bean Golden Yellow Mosaic, which
  prevents the plant from producing seed.

YIELD
In unmechanized agriculture yields of lima beans can be up to about 1.5 MT/ha, but
about 300–600 kg/ha is more common. In good conditions lima beans can produce
more than 3 MT/ha, and in North America yields of 4.5 MT/ha are common.
These high yields indicate the strong potential of this crop, though it is not
always easy to find good seed of varieties that are adapted to marginal conditions.

UTILISATION

• Dry beans—Lima beans are normally grown to produce the dry, mature bean,
  often called “butterbeans”. They are normally boiled, fried in oil or baked. Care
  should be taken as some older varieties, mainly the ones with dark seed colour,
  contain dangerous levels of poisonous cyanogenetic glucosides such as
  phaseolunatin and linamarin which can produce toxic HCN, hydrocyanic
  (prussic) acid. The dry beans contain adequate but not exceptional levels of
  protein (20%), fat (1.5%) and carbohydrate (60%). They are also used to
  produce protein-rich bean flour.


• Green pods—these are normally “picked and picked again”. In the tropics, and
  elsewhere, they are sometimes cooked and eaten as a green vegetable. In North
  America they are canned and also sometimes frozen, and the immature seed is
  canned or frozen.


• Leaves and stems—can be fed to animals direct, or made into hay or silage.


• Cover crop (page 63) and green manure crop (page 69).

LIMITATIONS

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• cooking time can be long for dark seed colour types, to destroy the poisons (see
  “Utilisation”, above). The beans should be either roasted or well boiled in two


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  this is often more of a benefit than a limitation for subsistence farmers).

  
  

176 TONY WINCH

The yield and cooking quality of lima beans can be disappointing.

Modern, improved varieties are in short supply.

changes of water.

are also frost sensitive.

Temperature requirements for growing a crop are quite specific, and the plants

Indeterminate growth habit of the climbing types and older varieties (though