2018 ASHS Annual Conference

Improved citrus management practices have become important as yields decline due to diseases, pests, and drought. Plastic mulch groundcovers are among some of the most promising practices being evaluated; improving water conservation by reducing evaporative losses from the soil, improving management of some pests and soil borne diseases, and limiting weed growth. These groundcovers can also promote deeper root systems and fine root production. In southern Texas, citrus are particularly vulnerable to drought due to the predominate method of flood irrigation, the subtropical climate, sporadic rainfall, and limited water resources. Flood irrigation causes significant water losses, nutrient losses, salt buildup, and erosion. Using alternative citrus management practices can potentially reduce the frequency and amount of water applied, but also has the potential to maintain water in the soil during times of drought and water scarcity. However, the initial cost of groundcover installation is a deterrent to many growers who would like to know if trees will come into production faster or yield more to defray the cost. To evaluate this, four management strategies were studied to evaluate tree growth rates and yield over 4 years and root growth and turnover for 2 years. Raised beds with groundcovers have led to increased root biomass, surface area, yields, and fruit weight. There were various impacts of groundcover and raised bed, but the combination of raised bed and groundcover seemed to have an additive impact on tree growth, yield, root production, and fruit quality. Furthermore, root biomass and area at deeper soil depths was increased compared to the conventional flat bed with no groundcover production system. Trees come into production faster and have greater yields, which should defray the costs associated with groundcover installation. Overall, using a raised bed with groundcover system shows positive impacts on production and holds much promise for citrus producers facing challenges due to water shortages, drought, or resource limitations.