Cultivation of Vegetables in River Bed
Author: Kavita sinha
Diara land farming or riverbed cultivation is very old practice (possibly started during Mughal period with various cucurbits) of growing vegetables on the bank or basin of river after when flood level receded. Presently, in South Asian countries, cucurbitaceous vegetables are extensively being grown in riverbeds (called diara land). These diara lands are formed and subjected to alluvion and diluvion action of perennial Himalayan Rivers and due to inundation caused by swollen rivers during South- West monsoon. Fresh silt and clay deposits received every year, during the monsoons months, especially in Himalayan Rivers, makes these lands suitable for growing vegetables crops, literally on sand. Even though upper layers of land seem unsuitable for growing crops, the subterranean moisture seeped from adjacent river streams, makes it possible to grow early crops. This system is unconnected with any other crop rotation and cucurbits are specially adapted to this system of growing due to their long tap root system. It can be treated as a kind of vegetables forcing where in the cucurbits are grown under sub- normal conditions, literally on sand, during winter months from November- February, especially in North and North- Western India. About 65% of total cucurbit cropped area of the country falls under riverbeds.
Importance and Scope
This system is unconnected with any other crop rotations and cucurbits are specially adopted to this system of growing due to their long tap root system. It can be treated as a kind of vegetable forcing wherein the cucurbits are grown under sub-normal conditions practically on sands. In U.P. these are grown on low priced sandy soils along the beds of the rivers. In Rajasthan these are cultivated on bare, active sand-dunes in sandy regions of Bikaner and other tracts of Rajasthan. These gives protection to dunes and no sand blowing takes place with their vines mulching the soil during summer months. Even though upper layers of land seem unsuitable for growing crops, the subterranean moisture seeped from adjacent river, streams, make it possible to grow early crops.
Some of the cucurbits viz. melon, water melon, cucumber, etc. are quite common and usually raised in the river basins during summer which is having a good market for small and marginal farmers.
Advantages of Riverbed cultivation
There are several advantages of river bed cultivation,
1. high net return per unit area,
2. early and high yield,
3. ease in irrigation,
4. low cost,
5. less mineral requirement due to high fertility
A well drained soil of loamy type is preferred for cucurbits. Lighter soils which warm quickly in springs are usually utilized for early yields, and in heavier soils vine growth will be more and fruits late maturing. In sandy river-beds alluvial substrate, and sub-terranean moisture of river streams support the cucurbits. In fact, a long tap root system is adapted to the growth of cucurbits in river-beds. The soils should not crack in summer, and should pot be water-logged in rainy season. It is also necessary that soils should be fertile and provided with adequate organic matter. All the cucurbits are sensitive to acid soils. Below pH of 5.5 no cucurbits can be successfully grown and most of the cucurbits prefer a soil pH between 6.0 to 7.0. Musk melon is slightly tolerant to soil acidity, while other cucurbits 'prefer intermediate or normal pH. Similarly alkaline soils with heavy salt deposition are unsuitable for cucurbits and water melon is the only cucurbit which is slightly tolerant to salts. Soil temperature is also a determining factor for quick germination, early maturity and production. The minimum temperature should not go below 10°C and maximum 25°C. The optimum range is around 18-22°C. In river-beds the sand remains comparatively warmer and does not cool quickly. Further, sandy river-beds have moisture beneath and warm up quickly in spring. That is the reason why cucurbits in river-beds survive low temperature periods of winter months and produce early crops in spring. Soil moisture is important for rapid growth and it should be at least 10% to 15% above the wilting point. Rainy season cucurbits are mostly unirrigated. Depth of the soil is also an important consideration in case of perennial cucurbits.
Growing of cucurbits in river-beds or river-basin constitute a distinct type of farming. The system consists of digging trenches at 2-3 meter spacing or pits at 4 meters apart (if the soil moisture is below 2 meters) after the cessation of south-west monsoon in late October. Most of the cucurbits are sown in November and December. Before sowing, the trenches are manured with FYM or any other organic decomposed waste or oil cakes. In North-Western India, when winter temperature go down very low, the protection is provided by planting grass stubbles (probably Saccharum spontaneous) species. This protection has three fold uses.
1. It checks the sand drifting on the dug up trenches, and covering the hills sown with seeds.
2. It provides partial protection against chilly wind.
3. The grass is also available for spreading over the sand when the vines grow and covers the sand.
It helps to prevent the sand being blown off with the vines, especially in summer due to hot winds. Due to prevalent low temperature, sprouted seeds are sown in trenches or pits in Nov-December and mixed cropping of several cucurbits like musk melon, water melon, pumpkin, bottle gourd, ridge and sponge gourds is practiced. In Bihar, pointed gourd is also grown in river-beds where sprouted and rooted cuttings are also transplanted. Plants are pot watered in the initial stages, until roots touches the water regime down below. In some parts of Andhra Pradesh, germinated seedlings are transplanted. After 25-30 days after sowing, depending on growth and weather conditions, top dressing of chemical fertilizers in two split doses is done, especially of nitrogenous fertilizers like urea or fertilizer mixtures. This top dressing is applied away from the plants in shallow trenches. Cakes like groundnut cake in Maharashtra and A.P. or castor cake in Gujarat are also applied. When the vines grow, they are spread over the sand and before that trenches are leveled up and the stubbles of grass are spread over the sand on the interspaces between the rows of the plants.
Pradeep kumar singh (2012), Cucurbits cultivation under diara- land. Asian Economic and Social Society. vol 2, 243-247.
About Author / Additional Info:
I am Deputy Project Director (ATMA) In Kanker