In the Philippines, the harvest of second season rice and second season maize concluded in April and May respectively. It was followed by the planting of main season maize and main season rice. Throughout the period, weather conditions were wetter than average (RAIN +18%). Temperatures remained normal (TEMP) and radiation was slightly lower by about 4% (RADPAR). The abundant rainfall and normal temperatures generally favor crop growth and biomass accumulation, resulting in a potential biomass that is about 2% (BIOMASS) higher. The slightly increased rainfall in April and May did not greatly affect the harvest of second season crops. However, the notably increased rainfall in June and July seems to have slightly affected the main season maize harvest. This is in line with the NDVI profile. According to the profile, crop NDVI remained slightly below average throughout April and May, and the gap widened after June.

Based on the spatial NDVI pattern, crop growth across the country can be classified into two patterns: 1) About 77.9% of the cultivated area (dark green, blue and orange) had NDVI values that were generally close to the average level during the period, indicating a normal crop condition in these areas. 2) Approximately 22.1% of the cultivated area (light green) had NDVI values well below average before June. They recovered to normal after June. These areas are mainly located in the northwestern region of Luzon Island.

Considering that the CALF index is close to 100% and the VCIx is as high as 0.95, with a CPI value of 1.11, it is estimated that both the harvest of the second season crops and the growth of the main season crops in the Philippines are generally normal.

Regional analysis

Based on the cropping systems, climatic zones and topographic conditions, three main agro-ecological regions can be distinguished for the Philippines. They are the Forest region (agro-ecological zone 153, mostly southern and western islands), the Hilly region (agro-ecological zone 154, Island of Bohol, Sebu and Negros), and the Lowlands region (agro-ecological zone 155, northern islands).

In the Forest region, precipitation has increased by about 17% (RAIN) and temperature by about 0.2°C (TEMP), leading to a 2% (BIOMASS) increase in potential biomass. The radiation in this region is about 4% (RADPAR) lower. The NDVI remained generally at average until mid-May, indicating that the harvest of the second season crops is generally normal. However, after mid-May, the crop NDVI remained slightly below average. Although the significant increase in rainfall in June and July is unfavorable for the maturation and harvest of main season maize, its impact appears to be limited. The VCIx value reached as high as 0.96 and the CPI value is 1.14, both indicating a generally normal crop growth status.

In the Hilly region, there was a significant increase in precipitation (RAIN +38%) and a 0.4°C (TEMP) decrease in temperature, accompanied by a 6% (RADPAR) decrease in radiation. The increased rainfall has led to an increase of about 3% (BIOMASS) in potential biomass, indicating that weather conditions during the period were generally favorable for crop growth. With the exception of certain periods, the crop NDVI remained largely at normal levels. However, there were sudden drops in late May and late July, which are thought to be related to cloud cover in satellite imagery. Despite these fluctuations, the VCIx value for this region is as high as 0.96 and the CPI value is 1.13, both of which indicate favorable crop conditions.

In the Lowlands region, precipitation has increased significantly by 16% (RAIN), while temperature and radiation have decreased by 0.2°C (TEMP) and 4% (RADPAR), respectively. The abundant rainfall has resulted in a potential biomass of about 3% (BIOMASS) higher than the average. The NDVI profile suggests that the increased precipitation may have an adversedly influenced NDVI, causing the NDVI to remain consistently below average. This suggests that the excess rainfall has not only adversely affected the harvest of the second season crops, but has also had an unfavorable effect on the growth of the main season crops. Nevertheless, the VCIx is as high as 0.93 and the CPI is 1.09. Therefore, overall crop growth in this region is expected to be normal.

Figure 3.35 Philippines' crop condition, April - July 2023

(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) Time series temperature profile (left) and rainfall profile (right)

(g) Crop condition development graph based on NDVI in Lowland region (left) and in the Hilly region (right)

(h) Crop condition development graph based on NDVI in Forest region

Table 3.61 Philippines' agroclimatic indicators by sub-national regions, current season's values, and departure from 15YA, April - July 2023

Table 3.62 Philippines' agronomic indicators by sub-national regions, current season's values, and departure from 5YA, April- July 2023