This report covers the grain filling period and harvest of winter-spring rice, followed by sowing of summer-autumn rice in the Mekong Delta and the southeast of Vietnam. In the central part, winter rice harvest is followed by summer rice planting in April. In the north, winter-spring rice was planted in January. It will be ready for harvest in May.

The proportion of irrigated cropland in Vietnam is 32%, which means that precipitation is important for the production of most crops in Vietnam. The agro-climatic condition showed the TEMP (22.6°C, +1.8°C) was above the average and the RADPAR (988 MJ/m², 0%) was close to the average. But due to a drastic decrease in rainfall (129 mm, -58%), the BIOMASS (555 gDM/m², -29%) dropped below the 15YA. The VCIx was 0.87, and the CALF (96%, 0%) was at the 5YA. The CPI in this monitoring period was 0.95, which indicated an unfavorable crop production situation.

Based on the NDVI development graph, the crop conditions were below the 5YA throughout the whole monitoring period except at the beginning of February. The precipitation was generally below the 15YA and was mostly concentrated in January and February. Temperatures exceeded the average from January to April except for late January. As to the spatial distribution of NDVI profiles, crop condition in 20.9% of the cropland (The dark green line and blue line. Located mainly in Ha Giang, Cao Bang, Tuyen Quang and Bac Can provinces) surpassed the average from January to February. The 20.9% of the cropland (The dark green line and red line. Located mainly in Lang son, Bac Giang, Thanh Hoa provinces) exceeded the average in mid-April. Crop condition in 68.3% region (The light green line and orange line. Mainly in Son La, Gia Lai, Ca Mau provinces) were generally below the average. The drops in NDVI are most likely caused by cloud cover in the satellite images. In general, crop conditions can be assessed as unfavorable.

Regional analysis

Based on cropping systems, climatic zones, and topographic conditions, the following agro-ecological zones (AEZ) can be distinguished for Vietnam: Central Highlands (213), Mekong River Delta (214), North Central Coast (215), North East (216), North West (217), Red River Delta (218), South Central Coast (219) and South East (220).

In the Central Highlands, the RAIN (42 mm, -84%) was well below average and the TEMP (23.3°C, 1.3°C) was above average, and the RADPAR (1164 MJ/m², 2%) had a slight increase. The resulting BIOMASS (449 gDM/m², -39%) was under the level of the 15YA. According to the NDVI development graph, crop conditions were generally lower than the 5YA during the whole monitoring period. The CALF was 96% and VCIx was 0.77. The CPI was 0.90. The crop conditions were estimated to be below the average.

In the Mekong River Delta region, the TEMP (28.9°C, 1.6°C) was above the average. The RAIN (16 mm, -95%) and RADPAR (1194 MJ/m², -2%) were below the15YA. The BIOMASS (458 gDM/m², -49%) was reduced. The CALF was 87% and the VCIx was 0.87. The crop condition development graph showed that the crop conditions were below the 5YA. The CPI was 0.97, which indicates that the crop productions were slightly lower than the average.

In the North Central Coast, although the TEMP (21.5°C, 2°C) and the RADPAR (926 MJ/m², 3%) were above average. Due to the sharp decrease of RAIN (186 mm, -48%), the BIOMASS (639 gDM/m², -23%) was below the average. CALF was 99% and the VCIx was 0.93. According to the crop condition development graph, the NDVI was close to the average in most of the monitoring period except a slight increase at the start of February, and there was a sharp drop in February and April, which may have been caused by cloud cover in the satellite images. The CPI was 0.98. The crop conditions in this region are a bit lower than the average due to the impacts of rainfall deficit.

In the North East region, the TEMP (18.9°C, 2°C) increased by 2°C and the RADPAR (700 MJ/m², -2%) decreased by -2%. However, similar to the situation in the North Central Coast, the RAIN (251 mm, -24%) showed a sharp decrease which caused a drop in  BIOMASS (693 gDM/m², -8%). The CALF was 99% and the VCIx was 0.93. According to the NDVI development graph, crop conditions fluctuated greatly. The NDVI was above the average except for the sharp drops in mid-January and mid- February. The reason for the decrease was caused by the cloud cover in the satellite images. The CPI was 0.97. The crop conditions were expected to be lower than the average.

In the North West region, the TEMP (19.6°C, 2.1°C) was above the average. RADPAR (960 MJ/m², -1%), was close to the average, and the BIOMASS (519 gDM/m², -22%) dropped by 22%, which was due to the decrease of RAIN (117 mm, -52%). The VCIx was 0.88 and the CALF was 100%. The CPI was 0.93. The crop condition development graph showed that NDVI was below average. The crop conditions in this region are expected to be unfavorable due to the drought.

In the region of the Red River Delta, the TEMP (20.7°C, 1.4°C) increased by 1.4°C and the RADPAR (644 MJ/m², 1%) increased by 1%. With the decrease of RAIN (270 mm, -14%), the BIOMASS (720 gDM/m², -7%) dropped by 7%. The CALF was 96% and the VCIx was 0.87. As shown by the crop condition development graph, the NDVI fluctuated greatly. In early January, February and April, the NDVI was at or surpassed the maximum of the past 5 years and was below the average in other months. The sharp drop in mid-Februarywas  becaused by the cloud cover in the satellite images. The CPI was 0.97. The crop conditions in this region were estimated to be below average.

In the South Central Coast, the RADPAR (1085 MJ/m², 3%) was a little higher than the average and the TEMP (22.3°C, 1.8°C) increased by 1.8°C. The RAIN (124 mm, -71%) was significantly lower than the 15YA, and the resulting BIOMASS (585 gDM/m², -34%) showed a sharp decrease by 34%. The CALF was 98% and the VCIx was 0.93. The crop condition development graph showed that the NDVI was above the average in January to February and below the average in March to April. The CPI was 0.99. Overall, the crop conditions in this region were below average.

In the South East region, TEMP (27.5°C, 1.5°C) was higher than the 5YA and RADPAR (1239 MJ/m², 3%) increased by 3%. With a significant decrease of RAIN (11 mm, -96%), the BIOMASS (382 gDM/m², -50%) decreased by 50%. The CALF was 92% and the VCIx was 0.74. The crop condition development graph indicates that NDVI was generally lower than the average. The CPI was 0.86. The crop conditions in this region were below average.

Figure 3.45 Vietnam's crop conditions, January 2024 – April 2024

（a）Phenology of major crops

     (b) Crop condition development graph based on NDVI

(c) Maximum VCI

                                           (d) Spatial NDVI patterns compared to 5YA                    (e) NDVI profiles

(f) National CPI time series

(g) Rainfall profiles

(h) Temperature profiles

(i) Crop condition development graph based on NDVI Central Highlands Vietnam (left), and Mekong River Delta (right).

(j) Crop condition development graph based on NDVI North Central Coast Vietnam (left), and North East Vietnam (right).

(k) Crop condition development graph based on NDVI North West Vietnam (left), and Red River Delta (right).

(l) Crop condition development graph based on NDVI South Central Coast Vietnam (left), and South East Vietnam (right).

Table 3.80 Vietnam's agroclimatic indicators by sub-national regions, current season's values and departure from 15YA, January 2024 – April 2024

Table 3.81 Vietnam's agronomic indicators by sub-national regions, current season's values and departure from 5YA, January 2024 – April 2024