Climate Information for Turnip Farming.
Turnip trees grow best in cool and moist climatic conditions. It requires short day lengths and long night lengths, a characteristic of the winter season, for better development of the roots. These trees require good sunlight during the critical stages of the growth period. In tropical climates, the trees remain evergreen. The moderate climate with cold temperature and moist conditions is best for the crop. Around 6-8 hours of direct exposure to sunlight is required for optimum growth of the turnip plant.
Tolerable range of temperature – The crop requires a bit less than the average temperature range of India for its optimum growth. The range stays between 10°C to 16°C. However, the Asiatic variety of the plant can still survive in a wider range of temperature than this. Temperatures less than 5°C along with frost and blizzard and more than 25°C can pose harmful impacts on the crop and reduce the yield.
Requirement of rainfall – Turnip trees require a lot of moist and humid climate with an evenly distributed annual rainfall of about 500 mm to 600 mm. However, Turnip trees can easily survive in rainfall lower than that. But, the trees are sensitive to water stagnation, and thus excessive rainfall with the absence of proper drainage leading to waterlogging may damage the root of the plants. So, in the case of high rainfall areas, the construction of an excellent drainage system should be the priority of the farmers.
Physical conditions like very high relative humidity, evenly distributed amount of rainfall and cold temperature conditions free from frost and blizzard are ideal for the voracious growth of the plants.
Suitable soil for Turnip Farming.
Turnip trees can be cultivated in a wide range of soils starting from sandy loam or alluvial soils of north India to deep clay loam or lateritic/acidic soils or black soils in the Deccan plateau and north-eastern hills. But, the best suitable soil conditions are well-drained and highly fertile sandy loam to medium-heavy soils with a high percentage of organic matter content and humus. Soils with poor drainage are not suitable. The optimum range of pH is from 6.5 to 7.5. pH value of 10 and more as well as 4 and less would result in very poor yields and would require appropriate soil treatments. For commercial cultivation of turnip, very light sandy soils or too heavy soils should be avoided at all costs.
Recommended Sowing Times for Turnip Farming.
The sowing times for various varieties of turnips are as follows –
Land Preparation for Turnip Farming.
Like all other commercial cultivations, an important task required for Turnip farming is proper land preparation. At least 2 to 3 thorough ploughings are necessary for making the field weed-free as well as for obtaining fine tilth of the soil. This would also level and clear the previously grown crops vegetation. The remaining soil clods after these ploughings should be crushed manually by country ploughs or other instruments since it favours germination. After opening up the topsoil, the land is left as it is for 15 days in the sun for sun-drying. This will ensure the elimination of the weeds and potential weed seeds. After that, about 25 tonnes of well-rotted farmyard manure (FYM) should be applied and spread evenly on the soil. Then, it should be properly mixed with the soil by means of further ploughing. After that, irrigation ridges, furrows and channels are created for further operations.
Sowing methods and tips for Turnip Farming.
The propagation of Turnip plants takes place only by means of seeds. No vegetative methods of propagation are practised. The seeds are sown by means line sowing method directly in ridges or lines prepared during the land preparation. The seeds should be sown deep into the soil (at least 1.5 cm) for proper nutrient availability and better chances of germination. However, in low lying regions affected by waterlogging, it should be done specifically on ridges.
Seeds of turnips should be sown on the rows 30 cm apart from each other. Row to row distance should be 6 cm to 7 cm. For uniform sowing, the seeds should be first mixed with sand.
No specific seed rate of turnip plants can be calculated.
Irrigation Methods for Turnip Farming.
Light irrigation is provided to the plants just after sowing and the subsequent irrigations are provided 8-10 days after irrigation. Turnip plants require a humid and moist climatic condition. So, depending upon the climate, water holding capacity of the soil and other soil characteristics, the frequency of the irrigation can be altered. Irrigations at a later stage can be provided at intervals of 15-25 days. The sprinkler method of irrigation should be applied for the purposes of saving water. In the case of winter rains, irrigation should be stopped for maintaining appropriate moisture conditions in the soil. But, in case of heavy rains and floods, the stagnated water should be quickly drained out from the soil.
Mulching also retains good moisture conditions in the soil apart from preventing weed growth.
Fertilizer Requirement for Turnip Farming.
25 tonnes of FYM per hectare of land is added as a basal dose during the time of land preparation. Under appropriate soil moisture conditions, the rates of application of various fertilizers should be –
Phosphatic and potassic fertilizers should be applied at a depth of 8 cm before sowing the seeds. Besides those, micronutrients like Zinc, Copper, Manganese, Iron, Boron, etc. are also necessary.
Best Seed varieties for Turnip Farming.
Turnips are mainly classified into two groups namely, Asiatic and European. However, some important commercial cultivars found in India include-
· Punjab Safed 4
· Golden ball
· Pusa sweti
· Pusa swarnima
· Pusa kanchan
Best Practices for Turnip Farming.
Weed control or intercultural operations – For Turnip plants, 3 hoeings at an interval of one or two months is necessary for controlling unwanted weeds since they affect the overall yield of the plants. After every harvest, weeding should be carried out to prepare the field for the upcoming batch. Chemical weedicides like Tok E-25 at the rate of 2 kg per hectare or terbutryn at the rate of 1 kg per hectare can also be used in these limits for better results. Mulching by means of 100-micron recyclable black polythene sheets is also a good alternative for controlling weeds. For organic mulching, 12 to 15 cm thick mulch should be used which will also facilitate penetration of water to the roots of the plants.
Harvesting – Turnips become ready for harvesting when good-sized tender roots can be uprooted without difficulty. The optimum size of roots indicating the harvest time of turnips is 6 to 10 cm in diameter. If the turnip harvest is elongated beyond the stipulated time, the roots get fibrous and tough and thus become unfit for consumption.