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Nutrient management practices of vegetable growers are under increasing scrutiny for their potentially adverse environmental effects. Monitoring of both soil and crop nutrient status have been advocated as fertilizer best management practices (BMPs). Since phosphorus fertilization is usually applied before planting, preplant soil testing for phosphorus availability is the most widely applicable BMP. While preplant soil nitrate analysis can be useful, particularly in semi-arid regions, presidedressing soil NO3-N testing has proven to provide reliable guidance on sidedress N requirement under diverse cropping systems and environments. Early in the cropping season when sidedressing decisions are typically made, Plant N analysis is poorly correlated with soil N availability, and often does not provide sufficient insight upon which to base sidedresss N applications. On-farm 'quick test' methods of soil and plant analysis have come into widespread use; the advantages and limitations of these methodologies are discussed.