Castor

Soils And Climate

Soils

  • Castor crop can be grown on a wide range of soils, provided they are fairly deep and well drained.
  • Heavy clays, with poor drainage, and marshy soils are unsuitable.
  • The highly suitable soils for castor are deep, moderately fertile, with slightly acidic conditions (pH 5.0 to 6.5), well drained , sandy loams.
  • Excessively fertile soils are not desirable, as they favour excessive vegetative growth at the expense of seed yield.
  • Castor does well in the soil which is not fit for valuble commercial and food crops.

  • Though castor can tolerate a pH of 8.0 but at this pH, the soil structure and soil physical properties will become the important limiting factors for castor cultivation.
  • In general all castor genotypes more particularly in seed production the female lines cannot tolerate alkalinity or salinity, hence, avoid such problematic soils.
  • The red chalkas (sandy loams) and shallow light textured black soils of Telangana (Nalgonda, Mahboobnagar, Rangareddy, Warangal, Karimnagar), Karnataka (Raichur, Mandya, Mysore, Tumkur, Hassan, Bangalore) and deep/medium sandy loams of North Gujarat (Sabarkanta, Mehasana, Banaskanta and Kutch districts) and Rajastan (pali and sirohi districts) are the principal soil types on which castor is currently grown.
  • It is equally successful in light and heavy loams of other states.

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Climate

  • Castor is essentially a warm season crop, cultivated in tropical,subtropical and temperate regions.
  • Its cultivation is largely confined to countries lying between 400N and 400S latitudes, but in Russia, a few varieties are grown even upto 520 North latitude.

  • In India it is being cultivated upto an attitude of 2500m, but in regions where frosts are common during the crop season, its cultivation is restricted upto 500 m.
  • A frost free growing period of 140-190 days depending on variety is highly essential for obtaining satisfactory yields.
  • It grows in tropical and subtropical regions as a perennial plant and in temperate climate as an annual plant.
  • A moderate temperature of 20-260C is highly favourable during crop period for obtaining higher yields.
  • Low temperatures (less than 150C) in the seed bed prolong the emergence of seedlings, and makes the seed more liable to attack by fungal diseases and insects.
  • Castor is sensitive to high temperatures especially at flowering.
  • A temperature of 410C or above even for a relatively short period results in blasting of flowers and poor seed set.
  • The effect is more marked if it coincides with moisture stress.
  • In the country, the kharif crop is often subjected to prolonged cloudy weather with high temperatures during flowering, which adversely affects the seed setting.
  • Generally, temperatures do not influence the oil content or level or composition of fatty acid.
  • Basically castor is a long-day plant and comes up well without marked reduction in yield under fairly wide range in day-length
  • The plant growth and development did not differ significantly when grown under different photoperiods of 12,14,16 and 18 hours.
  • Castor, being a deep rooted crop, is fairly resistant to drought. In our country, castor is widely grown as a rainfed crop in kharif season, with sowings between May and July.
  • A well distributed rainfall of 500-600 mm, during growing period will yield reasonably good yields.
  • However, in the country satisfactory yields are obtained on sandy soils receiving a rainfall of 300-500mm., using the varieties with capacity for extremely quick root growth.
  • In Telangana, a rainfall of 500-600 mm is optimum for producing good yields on red loams.
  • The ideal pattern of rainfall distribution for optimum growth, will be approximately 100 mm in each month evenly distributed during the crop growth period.
  • There should not be heavy and continuous rains during flowering.
  • Continuous rains prior to planting are also not desirable as it will lower the soil temperature effecting the germination and increase the fungal diseases.
  • Castor can with stand long dry spells as well as heavy rains but is highly susceptible to water logged conditions.
  • Hail storms do considerable damage to the crop especially during the seedling stage.
  • Defoliation due to hail prior to flowering will have little effect on final yield, but hail storm during flowering and capsule formation will cause considerable damage to the final yield.
  • In India, the crop is essentially taken up during kharif.
  • The availability of early maturing hybrids/varieties and improved agronomic practices has now made rabi or summer cropping possible under irrigation.
  • In case of seed production of castor climatic conditions prevailing in a season has profound influence on sex expression.
  • High temperatures coupled with humidity provide ideal climate for producing more male flowers and low temperatures is most conducive for production of female flowers and this is one reason why rabi/winter is the most ideal season for taking up hybrid certified seed production.

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Telangana

Castor

Castor Management