Assessing the Impact of Farming Method in Off-Season Period on the Productivity of Shallot (Allium cepa L.): The Case of Low-Organic Sandy-Clay Soil

The low productivity of shallot ‘Bima Brebes’ during the rainy season contributed to increasing Indonesia's economic inflation. This study aimed to assess the sustainability of shallot cultivation in low-organic sandy clay soil during the rainy season in South Sumatera, Indonesia. The study observed the farmer group's actual shallot cultivation method. The research findings were expected to explain the phenomenon of shallot production (Cohen f2) at least 0.50 with a maximum error rate (α) of 0.05 and a probability of making the right decisions (1-β) at least 80%. The variables included climate, soil characteristics, cultivation methods carried out by farmers, plant growth, and shallot production. The cultivated field has sufficient porosity to drain water quickly. Still, it tends to make compaction easier. The diameter of the shallot bulb produced fell into category 1 (size over 2.5 cm) by as much as 31.0%, category 2 (between 2.0-2.5 cm) by 38.0%, and category 3 (between 1.5-2.0 cm) by 17.8%. The loss caused by Fusarium disease was 20.29%. Sustainability of low disease-resistance shallot variety cultivation in low-carbon sandy clay soil during rainy seasons was possible by regulating soil humidity rather than fungicide application.