Response of Okra to Different Levels of Compost Application in Ogun State

This study examines the response of okra to different compost application rates in Ogun State, South West Nigeria. Okra is a nutritionally important vegetable crop widely consumed and commercially produced in Southwest Nigeria. Synthetic fertiliser costs and availability constrain smallholder vegetable production, making compost from crop residues and household organic waste a potentially viable nutrient management alternative. Compost improves soil organic matter, water retention, microbial activity, and nutrient availability, but optimal application rates for okra production in Ogun State sandy loam soils have not been established. This study establishes a randomised complete block design experiment at Olabisi Onabanjo University Agricultural Development Farm using five compost application rates: 0, 5, 10, 15, and 20 tonnes per hectare incorporated two weeks before planting. Plant height, stem girth, number of leaves, pod length, pod fresh weight, and total marketable yield are measured at weekly intervals and at harvest over two growing seasons. Findings reveal that 15 tonnes per hectare of compost produces the highest marketable okra yield of 9.8 tonnes per hectare, significantly above the no-compost control at 4.2 tonnes per hectare. Plant height and stem girth show consistent dose-response increases up to 15 tonnes per hectare. Beyond 20 tonnes per hectare, yield declines modestly due to excessive nitrogen-induced vegetative growth at the expense of fruit development. The study concludes that 15 tonnes per hectare is the optimal compost rate for okra in Ogun State conditions and recommends composting training for smallholder vegetable producers.

Keywords: compost application, okra yield, Ogun State, organic fertiliser, vegetable production.