Cropping Season/ Cropping Pattern in bangladesh

The dominant cropping patterns of Bangladesh are shown in the map below. Most areas allow three crops a year with the exception of the Sylhet hoar basin, the drought-prone areas in the west and the coastal areas. Rice is grown throughout the country with the exception of the Chittagong Hill Tracts. Wheat is predominantly grown in the north-west and in districts along the Padma river.  The main vegetable producing areas are in the west around the town of Jessore. The availability of fresh vegetables here may be an important factor for the low incidence of child malnutrition in this area.

Food supply varies according to the season, with domestic food supplies being scarce during the lean seasons in March–April and October–November, prior to harvesting. The lean seasons are characterized by a lack of agricultural employment opportunities, low agricultural wages and high rice prices. An annual phenomenon is the occurrence of “monga” (hunger), particularly in the north-western region of the country during this time.

Crop combination is a pattern of cultivating two or more crops in a cropping season. This practice provides farmers with opportunities for harvesting diverse crops from the same land, increasing total land productivity, and maintaining or improving soil fertility through use of legumes. The major cereal cropping system of Bangladesh is rice and wheat grown on the same field but in different seasons during the year. Although the rice-wheat cropping pattern is the major cereal production pattern, farmers are sowing continuous cereals year after year. Although the area of rice-wheat may not change within years on a national level, farmers themselves are changing their cropping pattern within their plots. Farmers sow pulses, oilseeds, potatos, vegetables and sugarcanes on the plots previously in rice-wheat. Commonly used 2-crop combinations are aman-boro rice, aman-aus rice and aman-boro rice, 3-crop combinations are aman-boro-aus, aman-boro-jute and aman-boro-pulse. 4-crop combinations are boro-aman-jute-mustard, boro-aman-mustrad-aus, aman-aus-boro-tea, aman-boro-jute-wheat, aman-wheat-boro-aus, aman-boro-wheat-aus, and aman-aus-maskalai-boro.

Because of its tropical location, Bangladesh is able to plant several crops on the same lamd each uear. The crop-growing period is divided into two main seasons, Kharif and Rabi. Crops (such as rice, jute, maize, millets, etc) which are grown during the Kharif season are called Kharif crops and those (such as wheat, mustard, chickpea, lentil etc) grown during the Rabi season are called Rabi crops. The Kharif season extends from May through October, while the Rabi seasons starts from November and continues up to April. In addition to these two main seasons, another transition season called Pre-kharif has been identified. This season starts from March-April and ends in May-June.

The major characteristics of the cropping seasons of Bangladesh are described below:

Pre-Kharif Season is characterized by unreliable rainfall and varies in timing, frequency and intensity from year to year, and provides only an intermittent supply of moisture for such crops as jute, broadcast aman, aus, groundnut, amaranths, teasle gourd, etc. During this transition period, soils intermittently become moist and dry. The relative lengths and frequency of such periods depend on the timing and intensity of pre-monsoon rainfall during this season in individual years.

With the expansion of irrigation facilities, some of the Pre-kharif crops are now grown under irrigated conditions. These include sugarcane, maize, jute, amaranths, groundnut, banana, sesame, lady's finger, teasle gourd, sweet gourd, white gourd, bitter gourd, balsam apple, ribbed gourd, Indian spinach, ginger, turmeric etc.

The Kharif Season starts from May when the moisture supply from rainfall plus soil storage is enough to support rainfed or un-irrigated Kharif crops. The season actually begins on the date from which precipitation continuously exceeds 0.5 Potential Evapotranspiration (PET) and ends on the date when the combination of precipitation plus an assumed 100 mm of soil moisture storage after the rainy season falls below 0.5 PET. During the greater part of this season, precipitation exceeds full PET and water can be held on the surface of impermeable soils by bunds. The period of excess precipitation is called the humid period.

The crops most extensively cultivated during the Kharif season are jute, aus, broadcast aman, transplant aman, sesame, different kinds of summer vegetables, ginger, turmeric, pepper, green chilli, different kinds of aroids, cotton, mungbean, black gram, etc. Most Kharif crops are subject to drought and flood in areas without water control.

The Rabi season starts at the end of the humid period and lasts to the pre-kharif season. The mean length of the Rabi growing period ranges from 100-120 days in the extreme west to 140-150 days in the northeast of the country. The mean starting date of the Rabi season ranges from 1-10 October in the extreme west, to 1-10 November in the Northeast, and in central and eastern coastal areas. The mean end dates range from 1-10 February in the following year in extreme west to 20-31 March in the Northeast. Most common Rabi or winter crops are wheat, maize, mustard, groundnut, sesame, tobacco, potato, sweet potato, sugarcane, lentil, chickpea, grass pea etc. On lowlands, very lowlands and bottomlands where flooding continues even after the end of rainy season, the Rabi season starts from the date when flooding ends.