This report covers the second season (Yala) sowing of rice and maize in June and July. According to the CropWatch indicators, crop conditions were normal for the period from April to July.

This period is dominated by the south-western monsoon, which is active between May and September. At the national level, precipitation significantly increased (RAIN +40%) and radiation also increased (RADPAR +1%), while temperature (TEMP -0.3℃) experienced a slight decrease as compared to the 15-year average (15YA). The increase in rainfall mainly happened in May. As shown on the NDVI development graph, NDVI values were always near average from April to May and slightly above average in early June and below average in July compared to the 5-year average (5YA). The fraction of cropped arable land (CALF) was 1% above the recent five-year average. Potential biomass was 2% above the 15YA. The maximum VCI (VCIx) for the whole country was 0.95.

As shown by the NDVI clusters map at the national level, 40.8% of cropland showed above-average condition from April to July. 7.8% of cropland showed a large decline of NDVI values in late May and early July, as well as 7.2% in late July, which may have been an outlier due to cloud cover. Overall, prospects for crop production are normal.

Regional analysis

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

In the Dry Zone, the recorded rainfall (RAIN 629 mm) was 50% above average, which could meet the water demand of maize growing in this region. The temperature was below average (TEMP -0.4°C) with increased radiation (RADPAR +2%) and above-average potential biomass (BIOMSS +3%)  compared with the 15-year average. CALF was 2% up compared to the 5YA level and cropland was near fully utilized. NDVI followed a similar trend as the whole country. The VCIx for the zone was 0.94. Overall, crop conditions were close to the average for this zone.

The Intermediate zone went through the rainy season during this monitoring period. Rainfall (RAIN 1358 mm) was up by 46% when compared to the 15YA. Temperature, radiation and potential biomass were below average (TEMP -0.4°C, RADPAR -1% and BIOMSS -1%).  NDVI followed a similar trend as the whole country. The VCIx value for the zone was 0.96. Overall, crop conditions were average for this zone.

The Wet zone also experienced an abundant precipitation (RAIN 2534 mm), 34% above the 15YA. This is more than sufficient for rice and maize. The temperature was down by 0.1°C compared to the 15YA with radiation close to the 15YA. With full use of cropland, potential biomass was close to the average for this zone. NDVI values were below average except for near average in early May and above average in late June. The VCIx value for the zone was 0.96. Crop conditions were assessed as close to the average for this zone.

Figure 3.27. Sri Lanka crop condition, April 2021 - July 2021

(a) Phenology of major crops

(b) Crop condition development graph based on NDVI

(c) Rainfall profile

(d) Temperature profile

(e) Maximum VCI

(f) Spatial NDVI patterns compared to 5YA  (g) NDVI profiles

(h) Dry zone crop condition development graph based on NDVI (left), time series rainfall profiles (middle) and temperature (right)

(i) Wet zone crop condition development graph based on NDVI (left), time series rainfall profiles (middle) and temperature (right)

(j) Intermediate zone crop condition development graph based on NDVI (left), time series rainfall profiles (middle) and temperature (right)

Table 3.45. Sri Lanka agroclimatic indicators by sub-national regions, current season's values and departure from 15YA, April 2021 - July 2021

Table 3.46. Sri Lanka agronomic indicators by sub-national regions, current season's values and departure from 15YA/5YA, April 2021 - July 2021