How to Grow Castor/Production Technology of Castor
Scientific name: Ricinus communis L.
Importance of Castor
Castor is grown for its seeds. The oil extracted from Castor seed is being used widely for various purposes. It is used as a lubricant in high speed engines and aero planes, in the manufacture of soaps, transparent paper, printinginks, varnishes, linoleum and plasticizers. Castor seeds are also being used for medicinal and lighting purposes. The Castor may be used to make manure and plant stalks as fuel or as thatching material or for preparing paperpulp.
Varieties of Castor
The varieties (cultivars) of castor differ in the branching habits of plant, colour of the stem and branches, the nature of capsules, duration, the size of seed and oil content. Here are some of the high yielding castor varieties available in India; NPH1, GAUCH4, YRCH 1, TMV 5, TMV 6, CO 1 and TMVCH.
Castor crop can be grown from sea level to altitudes of about 1000 meter (m.s.l). Castor crop requires a hot, dry climate with annual rainfall of 500-800 mm of which 500-600 mm is needed during the first 3 months of crop growth. Castor is an ideal crop for marginal lands of the Dry Zone where it can be grown under both rainfed and irrigated conditions. This crop is sensitive to high humidity and high temperatures above 40°C and impacts the crop yield.
Generally, Castor is cultivated in lands which are not suitable for commercial farming. Castor seeds can be grown on a wide range of soils which are fairly deep and well drained. The most suitable soils for castor cultivation are deep, moderately fertile with slightly acidic conditions and well drained sandy loam soils. The ideal soil pH of soils should be around 6.0 for better yield. However, it can be cultivated on soils with pH range of 5.0 to 8.5.
Give 3 or 4 deep ploughings to loosen up the soil as this crop requires well pulverized 40 cm deep loose subsoil for good seed germination. Land or seed bed should be weed free and any weeds from previous crops should be removed. The clods should be crushed by using a country plough or harrow with onset of monsoons.
A seed rate of 10 to 12 kg is more than enough to cover 1 hectare land. Again, seed rate depends on cultivar (Variety) and sowing method.
Seed Treatment of Castor
It is recommended to treat the seeds with Carbendazim @ 2 grams/kg of seed for preventing seed borne diseases like rootrot and Alternaria blight. Soaking the seeds in water for 18 to 20 hours is advised. In rainfed situations, seed priming with 1% Kcl for 3 hours and sowing 7 days before onset of monsoon is recommended.
Propagation of Castor
Propagation of Castor crop is done through seeds.
Sowing of Castor
Castor bean is usually planted just before the rainy season in the month of June. However, it can be cultivated throughout the year in areas where irrigation facility is available.
• Row to Row: 90-120 cm.
• Plant to plant: 4060 cm.
The seed should be sown either by plough furrow or with a seed drill or by hand dibbling.
Intercultural Operation of Castor
Gap Filling: Gap fill should be carried out on the 15th day of sowing and simultaneously thinning should be done leaving one healthy plant.
Weed Management: Weed control is very important in any crop as it impacts the overall yield as weeds compete for nutrients, fertilizers, manures and water. One or two weeding and hoeing with bullockdrawn implements should be given and sometimes, the plants should be earthed up. Chemical weed control like weedicides can also be effective to prevent the weed growth. Apply pre emergence herbicide Pendimethalin @ 3 liter/ha or Fluchloralin @ 2 liter/ha on 3 days after sowing followed by hand weeding twice on 21 st & 40th day after sowing the seed.
Irrigation Rainfed crops don’t need any irrigation. However, in irrigated crop, water should be provided weekly twice. Frequency of irrigation depends on the soil type, climate and crop stage.
Farmers can earn some extra income by going for inter crops. Groundnut/Peanut, black gram, green gram can be cultivated along with Castor crop. For every row of Castor, 6 rows of peanut or black gram can be cultivated. Intercropping of castor with Green gram or Black gram in 1:2 ratio is recommended for rainfed condition. Intercropping of castor with onion in 1:2 ratio by adopting 1.5 x 1.0 m spacing is recommended for irrigated condition.
Manures and Fertilizers
♦ Spread 12 to 13 tons/ha of well decomposed farm yard manure (FYM) or compost evenly on the main field before last ploughing and incorporate in to soil by working a country plough.
♦ Apply 25 kg sulphur/ha through gypsum at the time of last ploughing for higher castor yield. Timely application of manures and fertilizers ensures the good crop growth and yield.
♦ the castor crop requires a fertilizer dose of N: P: K as 40:40:20 kg/ha. As a basal application, apply full dose of ‘P’ and ‘K’ and half dose of ‘N’. The remaining half dose of ‘N’ should be applied 1 month after sowing when the soil moisture is adequate.
Pests and Diseases of Castor
The common and serious pests in Castor cultivation are capsuleborer and semilooper. To control these pests, dusting BHC 10% in early stages or spraying 0.1% Carbaryl on the crop should be carried.
The other soil borne diseases like seedling blight and Alternaria blight are also major concerns in Castor crop. Water logged areas, lowlying areas should be avoided to prevent the seedling blight.
Harvesting of Castor
Time: The maturity of the crop depends on the variety. Most of the improved cultivars mature in about 140 to 175 days.
Maturity symptoms: The easy indication of Castor maturity is when 1 or 2 capsules in bunch show signs of drying. The whole cluster should be removed and stacked. The harvesting of unripe capsules has an adverse effect on the oil content of the seed and these should be avoided. It is recommended to collect the fruits when they ripen.
Threshing: After collecting entire crop, it should be dried in sun for couple of days and threshing should be done by beating the dried capsules with the help of stick. In rural areas, farmers use bullocks for threshing these crops. Winnowing should be done in the usual manner. One can use Castor Sheller as well to separate the seeds.
Yield of Castor
Generally, yield of any crop depends on factors like cultivar (variety), soil type, irrigation, climate and cultural practices. On an average the following yield can be obtained.
• From rainfed crop: 250 to 500 kg/ha.
• From mixed crop: 100 to 200 kg/ha.
• From irrigated crop: 550 to 800 kg/ha.