Maha (October to March) and Yala (April to September) are the main agricultural seasons in the wet areas in Sri Lanka. The driest area (in the east) tends to have only one rain-fed season (Maha) while the south-west enjoys a very long season with bimodal rainfall. Farmers cultivate maize and rice in rotation during both seasons. The monitoring period thus covers sowing and early growth of Maha maize and rice.

Crop condition over Sri Lanka was generally slightly below average.

The agro-climatic indicators showed minor change compared to average. Rainfall and radiation increased by 2% and 3%, while temperature dropped 0.6℃. The cropped arable land fraction (CALF) was 100%, 1% up compared to 5-year average, showing fully utilized cropland. BIOMSS is 2% up compared to 5-year average. According to the national NDVI development graph crop condition was initially low in early October (lower than the 5-year average) but improved, reaching average values by late November and above average and even the 5-year maximum in early January. Values fell again to below average in late January but, at 0.98,  maximum VCI stands for unusually good crop condition.

Spatial variability was significant throughout the country according to spatial NDVI patterns and profiles. In 42.5% of cropland, mostly in the south-east (centered around Uva province) , crops were perfectly average throughout the early Maha season. Negative departures occurred at different times and in different areas: (1) early in the season in 19.2% of cropland, located mostly in the districts from Galle to south Puttalam on the western coast; (2) late November in scattered locations in central Sri Lanka (9% of cropped areas, in Polonnarua and south Anradhapura); (3) late January from north Amapara to south Trincomalee districts. The maximum VCI map, however, indicates favorable values over the whole country with values below 0.8 in few areas only (e.g. central Ratnapura district).

Regional analysis

Based on the cropping system, climatic zones and topographic conditions, three sub-national agro-ecological regions can be distinguished for Sri Lanka. They are the Dry zone, the Wet zone, and the Intermediate zone.

The Dry zone, which is the largest of the three and located in the eastern half of the country (from north to south)  showed agro-climatic conditions akin to those of the whole country. Rainfall and radiation increased by 1% and 3% while temperature decreased by 0.6℃, compared to average. Crop condition was also similar to the nationwide situation. The maximum VCI map displays some isolated low values along the coast. Crop condition is satisfactory.

The Wet zone covers the smallest area (in the south-west) as well as the most favorable agro-climatic condition among three sub-national regions. The rainfall and radiation were above average by 11% and 5%, while temperature was below average by 0.5℃. Crop condition is average.

The Intermediate zone is located between Dry zone and Wet zone. Agro-climatic indicators were the “least favorable” among the three sub-national regions, although the wording hides the fact total rainfall was in the range of 900 mm, i.e. amply sufficient for any type of crop. The rainfall and temperature both were slightly below average while radiation increased by 2%. According to the NDVI development graphs, crop condition was average(VCIx at 0.97)

Mostly on the basis of fully utilized cropland, close to average agro-climate and very high VCI (0.99, 0.93 and 0.97 respectively), crop prospects are assessed as fair to good.

Figure 3.27. Sri Lanka cropcondition, October 2018 - January 2019

(a) Phenology of major crops

(b) Crop condition development graphbased on NDVI

(c) Maximum VCI

(d) Spatial NDVI patterns compared to5YA   (e) NDVI profiles

(f) Crop condition development graph based on NDVI( Dry zone (left) and Wet zone (right))

(g) Crop condition development graph based on NDVI (Intermediate zone)

Table 3.50. Sri Lanka agroclimatic indicators by sub-national regions,current season's values and departure from 15YA, October 2018 - January 2019

Table 3.51. Sri Lanka agronomic indicators by sub-national regions,current season's values and departure from 5YA, October 2018 - January 2019