The monitoring period covers the entire cycle of Yala rice (second rice) and maize, which are planted in April and May. According to the CropWatch monitoring results, crop condition was generally below average for the whole period.

At 689 mm, rainfall was 20% below average, while temperature was up by 0.6°C and radiation was average. The fraction of cropped arable land (CALF) remained comparable to the 5-year average. BIOMSS slightly increased (up 1% above average) as the recorded rainfall is sufficient to sustain crop growth. The NDVI development graph displayed unfavorable crop condition throughout the period. Crop condition deviated below average since April and has remained so. Similar conditions also occurred in three AEZs as described below. Poor performance of NDVI profiles may result from the effect of relatively "dry" weather on natural vegetation more than  on crops.

Spatial heterogeneity of crop condition was significant throughout the country’s cropland according to NDVI clusters map and profiles. 25.1% area of cropland distributed in some scattered areas over Trincomalee, Polonnaruwa, Badulla, Hambantota, Galoya and Amparai, displayed positive NDVI departure values for the whole period. 11.8% of cropland in the South-east and East displayed below-average crop condition since April and but changed to above-average after June. 14.6% of cropped areas mostly in the North-Central and North-western Provinces had consistently low NDVI at -0.15 units below average. Remaining areas are cloe to average. The VCIx only partially confirms  NDVI clusters because of the very scattered distribution of all the indicators.

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.

The Dry zone plants mainly maize next to rice. The rainy season lasts from September to January in the north and from September to March in the south, with rainy seasons lasting between 120 days and 300. The monitoring period is out of the rainfed season;  the recorded RAIN (278mm) was 31%  below average, and amounts to just over 2mm per day, which is insufficient for rainfed crops, and needs to be supplemented by irrigation. TEMP was 0.7°C up and RADPAR was near average (-2%), with BIOMASS average. Overall, crop conditon was not as good as the average of the previous five years.

The Intermediate zone has two long rainy seasons in the west (March-June and September-December) and one in the east (September-April) and last between 300 and 365 days. During the monitoring period, RAIN reached 676mm, equivalent to about 6mm per day and sufficient for all crops, even  though RAIN was 25% below average. RADPAR and BIOMASS were both average while TEMP increased by 0.5°C. Condition of rice was generally normal for the zone.

The Wet zone has almost no dry season, and provides ideal conditions for the cultivation of rice. RAIN was 1662mm (14 mm/day) and 13% down compared to average. RADPAR and BIOMASS both increased by 7% with 0.6°C up in TEMP. Crop condition for the zone does not rise any concerns. 

Figure 3.21. Sri Lanka crop condition, April 2019 - July 2019

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

(i) 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, April 2019 - July 2019

Table 3.51. Sri Lanka agronomic indicators by sub-national regions, current season's values and departure, April 2019 - July 2019