Determination of Planting Time of Watermelon Under a Shallow Groundwater Table in Tidal Lowland Agriculture Areas of South Sumatra, Indonesia

Watermelon cultivation is one of the appropriate alternatives in order to increase farmers' income from tidal lowland agriculture. Research into crop adaptation to wet soil conditions is required to enable farmers to decide the best planting time under various conditions within the existing land classification. The research to determine crop physiological response during the initial growth period was conducted in a greenhouse. This was combined with field treatments based on groundwater table depths at 15, 10 and 5 cm-surface, respectively. Analysis of crop potential based on the water status conditions in the root zone was conducted by using secondary and primary data (daily records). Results of crop adaptation at shallow groundwater table depth showed that the treatments with groundwater table depth of 10 and 5 cm-surface were not significantly different in terms of plant height, with a size of 12.6 and 12.3 cm, having three leaves. However, it had a significant effect on root length, with a length of 11.9 and 3.1 cm, respectively. Maximum plant height of 15.2 cm and four leaves were found for the treatment with a groundwater table depth of 15 cm-surface. It may be concluded that it is best for farmers to plant at a groundwater table depth of 10 cm-surface. (c) 2019 John Wiley & Sons, Ltd.