Nutrient Removal Amounts by Major Vegetable Crops in Texas

A balance between nutrient inputs and crop removal is required for effective long-term crop production. Although nutrient removal estimates are readily available for many field crops, such values for fruit and vegetable crops are rare. The objective of this project is to determine nutrient removal values for major fruits and vegetable crops grown in South Texas, and to use the information to help refine fertilizer recommendations for yield and quality.

During the spring growing season of 2011, nutrient removal amounts were estimated for muskmelons and onions from fields that were previously investigated in 2009. Removal rates by grapefruits from commercial orchards were also estimated (2011 only). Average melon yield in 2011 was 19.8 tons/A with nutrient removal averaging 92 lb N/A, 18 lb P/A, and 121 lb K/A. Sweet onion bulb yields in 2011 averaged 13.8 tons/A with average nutrient removal of 61, 19, 75 lb/A for N, P, and K, respectively. Grapefruit yields averaged 12.2 ton/A fresh fruit and nutrient removal averaged 29 lb N/A, 8 lb P/A, and 66 lbs K/A.

Continued sampling over multiple years and locations with varying weather conditions, soil types and yield scenarios will be needed to establish realistic nutrient removal values that can be used to develop improved fertilizer management guidelines. Support for this work will continue in 2012. TX-55