Impact of Organic Mulching on Weed Suppression, Soil Moisture Conservation and Yield in Vegetable Crops: A Comprehensive Review

Abstract

Mulching is a time-tested agro-technique that significantly enhances vegetable crop performance, especially under water-limited and organic production systems. Organic mulching, which involves the use of biodegradable materials such as straw, hay, leaves, compost, and plant residues, has gained renewed attention due to its multifaceted benefits. This review consolidates recent findings on the impact of organic mulching on weed suppression, soil moisture conservation, and crop yield enhancement in vegetable crops. Organic mulches effectively suppress weed emergence by creating a physical barrier and blocking light, which limits seed germination and seedling establishment. In particular, they are most effective against annual broadleaf weeds and small-seeded species, though less so against aggressive perennials. Mulching also enhances soil moisture retention by reducing evaporation, moderating soil temperatures, and improving water infiltration. These effects are particularly beneficial in arid and semi-arid climates, where water availability is a major constraint. Furthermore, the gradual decomposition of organic mulch improves soil structure, microbial activity, and fertility, thereby promoting healthier root systems and better plant growth. Studies in vegetables like tomato, chilli, okra, brinjal, and cucumber have shown significant increases in yield, biomass accumulation, and fruit quality under organic mulching. The practice also helps maintain soil health over the long term and reduces the need for frequent irrigation and chemical weed control. Integration of organic mulching with other agronomic practices can enhance its effectiveness and mitigate its limitations. However, challenges such as labour-intensive application, possible introduction of weed seeds, and the risk of nitrogen immobilization must be managed for optimal outcomes. Overall, organic mulching stands out as a sustainable and ecologically sound practice to enhance productivity and resource efficiency in vegetable cultivation systems.