Cascade hydroponics enhanced water and nutrients use efficiency in a greenhouse cucumber-melon crop combination

Summary

This field trial evaluated a cascade soilless system in which cucumber crop drainage was recycled to irrigate a melon receiver crop grown in perlite slabs, compared to conventional melon monoculture. The cascade system substantially improved water and nutrient use efficiency (water by 22%, nitrogen and phosphorus by approximately 22% each) whilst maintaining melon plant growth and yield, and achieved remarkable reductions in nitrogen and phosphorus leaching to the environment (70% and 86% respectively). The findings suggest cascade soilless systems offer a sustainable intensification pathway for horticultural production in the Mediterranean region by decoupling input intensity from productivity.

Regional applicability

The study was conducted in Greece and addresses horticultural intensification in the Mediterranean region. The cascade soilless system approach is directly transferable to protected horticulture systems in the United Kingdom, particularly commercial greenhouse operations, where water scarcity and nutrient leaching are increasingly important policy drivers. However, UK growers would need to adapt the system design for different climate conditions and potentially different crop combinations suited to UK demand.

Key measures

Water use efficiency (22% increase), nitrogen use efficiency (21.7% increase), phosphorus use efficiency (21.8% increase), potassium use efficiency (9% increase), nitrogen leaching reduction (70%), phosphorus leaching reduction (86%), plant growth, crop yield, mineral composition of nutrient solution

Outcomes reported

The study measured water use efficiency (WUE), nitrogen use efficiency (NUE), phosphorus use efficiency (PUE), potassium use efficiency (KUE), plant growth, yield, and nutrient leaching in a cascade soilless system versus monoculture controls. The cascade system, wherein cucumber drainage irrigated a melon crop, was compared to standard melon monoculture in terms of resource efficiency and environmental impact.

Topic tags