Concurrent Session 2B
Improving irrigation and nitrogen management of coastal vegetable and berry crops
Michael Cahn, UC ANR Cooperative Extension Advisor, Monterey County
Abstract: Growers of vegetables, strawberries and caneberries along the coastal regions of California are under severe regulatory pressure to limit off-site movement of nitrate into ground and surface water. Additionally, this region has severe limitation in water supplies, relying mostly on ground water to meet crop water requirements. More than a decade of concentrated field research on the central coast has documented irrigation and N uptake requirements of two major crops (lettuce and strawberry), and has identified cultural practice modifications that could substantially improve fertilizer and water use efficiency. Much less information is currently available for other important crops in this region (broccoli, cauliflower, cabbage, celery, high-density salad greens, peppers, blackberries, and raspberries. This project proposes to complete the development of data on water and N management of the coastal crops. A team, consisting of 10 advisors and specialists, are collaboratively working on collecting data from commercial fields along the Central Coast to fill gaps in information needed to provide comprehensive recommendations on water and N fertilizer management. These gaps include crop coefficients for irrigation scheduling, seasonal crop N uptake patterns, and N mineralization of crop residues. Detailed guidelines on water and nutrient management for coastal crops will be written as a series of ANR 8000 online publications that can be used by growers, crop advisers, and consultants for developing fertilizer management programs and irrigation schedules. Additionally, collected data will be used to expand CropManage (ucanr.edu/cropmanage), an online decision support tool for nitrogen and water management. CropManage was piloted for lettuce, and allows growers to tailor water and N fertilizer recommendations for specific soil and climatic conditions of their fields, and development stage of their crop. For CropManage to be truly useful to the agricultural industry, the software will need to be expanded to address all major crops grown on the coast.