Determining Length of Growing Period for Crop Planning in East and South Eastern Coastal Plain Agroclimatic Zone of Odisha

The length of the growing period (LGP) refers to a number of days in a year during which the moisture at the root zone of crop plants is adequate to meet the crop water need. Information on LGP provides a basis for the selection of crops, cultivars (short / medium / long duration) and cropping/farming systems of a region.

Aim: The study aims to estimate the length of crop growing season of the East and South Eastern Coastal Plain Agroclimatic Zone of Odisha in order to provide a basis for suitable crop planning for the region.

Methodology: The LGP for four districts (Jagatsinghpur, Kendrapara, Khordha and Puri) under East and South Eastern Coastal Plain Agroclimatic Zone of Odisha was estimated using rainfall data of 30 years (1991 to 2020). The growing season begins when the sum of daily rainfall (forward accumulation) reaches 75 mm (28 May, 29 May…15 Oct) and ends when backward accumulation (15 Oct, 14 Oct,……, 28 May) of 20 mm reach. The LGP was worked out by adding the duration of the rainy season with the sum of post-monsoon rainfall and the average water-holding capacity of soil divided by the post-monsoon PET of the district.

Results: LGPs obtained by the above method varied from 173 to 192 days in this zone with Kendrapara district having the highest LGP (192 days) and Khordha the shortest (173 days). The date of onset and cessation of south west (SW) monsoon was 15-17 June and 13 October, respectively.

Conclusion: Double cropping can be followed in Jagatsinghpur, Kendrapara and Puri districts where the length of the growing period >180 days except Khordha district where paira cropping can be followed as the length of the growing period <180 days.