Evaluation of a simple re-circulating hydroponic system for sweet pepper (Capsicum annum L.) and pechay (Brassica napus L.)

Abstract

This study assessed the growth, yield and profitability of sweet pepper and pechay grown in a simple, locally designed re-circulating hydroponics system (RHS) provided with coarse river sand and coco-coir dust as aggregates at different ratios. The system consisted of 6 pans (40-cm wide, 2.2 m long, 10 cm deep) made of galvanized iron (G.I.) sheets. The nutrient solution is delivered from a plastic drum by gravity to the aggregates through a system of polyvinyl chloride (PVC) pipes provided with small holes. Each end of the pan is provided with a hole where excess solution drains into a collecting container, which is then re-circulated back into the drum. The performance of the crops under this system was compared to those grown under the conventional (soil-grown), and Simple Nutrient Addition Program (SNAP) hydroponics system. Pechay plants grown in the RI-1S were taller, produced more leaves, had faster growth and development and had higher yield compared to those grown in SNAP hydroponics and conventional system. Sweet pepper plants grown in the RHS also had better growth and higher yield compared to the SNAP hydroponics and conventional production systems. The ratio of coarse sand and coco-coir dust as aggregate for the RHS did not significantly affect growth and yield of the two crops. A projected cost and return analysis considering a pechay-pechay-sweet pepper-pechay-pechay-sweet pepper 1-year crop rotation scheme revealed that the use of RHS had higher profitability compared to the other two production systems.