Ending composting during the thermophilic phase improves cultivation substrate properties and increasing winter cucumber yield

•Incompletely composted materials improve substrate properties.•Compost fermented for 35 days is a suitable substrate for cucumber production.•Incompletely composted materials increased the root temperature by 1.0–2.2 °C.•Incompletely composted materials increased winter cucumber yield. In the world, 10 billion tons of solid wastes were produced each year. Composting is a better method for solid waste management. Vegetable production now tends to be soilless cultivation. However, completed compost is not suitable for vegetable cultivation. So we studied bagasse (BS), corncobs (CC) and sawdust (SD) as composting materials and investigated stopping in the thermophilic phase for different durations (35, 45, and 65 days). Subsequently, cucumbers were transplanted into nine composted samples mixed with vermiculite at a ratio of 1:1 (v/v). The results obtained during the composting of the three composts (BS, CC and SD) showed that composting for 35 and 45 days increased the root temperature by 1.0–2.2 °C during January and February compared to the effects of composting for 65 days. In addition, microbial community numbers were significantly increased (P