The monitoring period covers the sowing and growth of spring and winter rice in both the north and south of the country, with differences due to altitude. Most rice is cultivated in the Red River Delta (north)  and in the Mekong Delta in the south. 

Nationwide, the condition of crops is above the reference 5YA in 30.6% of croplands (mainly in the south-east of the country) where a VCIx above 0.8 confirms the favorable situation. Unfavorable crops occur in about 29.2% of the arable land (mainly in the north-west of the country). Due to the erratic behavior of NDVI (possibly due to cloudiness) its interpretation is inconclusive. Compared with average, precipitation decreased 6%, while the temperature (+1.2°C) and RADPAR (+6%) both increased. The biomass production potential was up 3% above average, with high CALF up +1% and a very favourable VCIx of 0.98. CropWatch currently predicts the rice output to be below 2018 values.

Regional analysis

Based on cropping systems, climatic zones, and topographic conditions, several agro-ecological zones (AEZ) can be distinguished for Vietnam, among which three are most relevant for crops cultivation: Northern zone with Red river Delta, the Central coastal areas from Thanh Hoa to Khanh Hoa and Southern zone with the Mekong Delta.

The Northern zone with Red river Delta recorded about average rainfall (RAIN +6%), RADPAR (-2%) but high temperature (TEMP 1.6°C above average). With high CALF (99%) and VCIx (1.00), the BIOMSS significantly increased (+17%)  compared to the average. The NDVI development graph showed an unstable trend with values above the 5 years maximum in April. Based on the agro-climatic indicators and NDVI development graph, output is likely to be average or above.

The situation and expected impact on crop production in the Central coastal areas from Thanh Hoa to Khanh Hoa is conditioned by low precipitation (RAIN -10%), high temperature (TEMP +1.7°C) and abundant sunshine (RADPAR +16%). BIOMSS is down 2% but VCIx (1.01) and CALF (+1%) describe fair to good condition. The crop condition development graph based on NDVI was above the 5 years maximum during February but decreased after March. Below average output is likely for rain-fed crops but irrigated crops should be doing fine.

The fraction of cropped arable land (CALF) in the Southern zone with the Mekong Delta for the reporting period is close to  average (up 1%). Vegetation condition indices (maximum VCI) are favorable (0.94), accompanied by a decrease in BIOMSS (-7%) resulting from the obvious shortage of precipitation (RAIN -17%) along with an increase in radiation (RADPAR +6%) and average temperature (TEMP, +0.5°C). The crop condition development graph of NDVI indicates values that are below the 5 years average and last year's condition. CropWatch expects below average production in the area.

With crop condition in over 60% of the croplands average or below average, crop prospects are expected to be average or below.

Figure3.33. Vietnam crop condition, January -April 2019

Figure3.33a. Vietnam phenology of major crops 

Figure3.33b. Vietnam national level crop condition development graph based on NDVI,comparing the January -April 2019 period to the previous season and the five-year average (5YA) and maximum

Figure3.33c. Vietnam maximum VCI for January -April 2019 bypixel

Figure3.33d. Vietnam spatial NDVI patterns up to April 2019 according to local cropping patterns and compared to 5YA (left) and (e) associated NDVI profiles(right)

Figure3.33f. Southern Vietnam (Vietnam) crop condition development graph based onNDVI

Figure3.33g. Northern Vietnam (Vietnam) crop condition development graph based onNDVI

Figure3.33h. Central Vietnam (Vietnam) crop condition development graph based on NDVI

Table3.87  Vietnam agroclimatic indicators by sub-national regions, currentseason values and departure from 15YA, January -April 2019

Table 3.88 Vietnam agronomic indicators by sub-national regions, current season values and departure form 5YA/15YA, January - April 2019