Nursery fertilizer best management practices

Best management practices for nutrient management in nurseries can be divided into fertilizer product management and irrigation management. Here’s a short list of items to consider when planning a nutrient management program for the nursery.

Release types:

• Osmotic, timed release
• Microbial, temperature dependent, slow release
• Water soluble, quick release
• Mechanical, timed release

For safety, keep fertilizer products:

• Locked and protected
• Well-lighted
• Well-ventilated
• Separate from pesticides
• Liquid formulations separate from solids/granular
• Dry and safe from wide temperature swings

Dry fertilizer application options:

• Dibbling
• Incorporation
• Topdressing

Each method has its own benefits and drawbacks. Dibbling places the material directly below the root system. It poses the highest potential for burn and is labor intensive. Incorporation requires the largest amount of fertilizer, but is cheapest to apply. Up to 30 percent of the fertilizer can be lost before the roots reach the fertilizer. Topdressing is the most labor intensive. It has a high potential for loss (if a pot falls over, product spills out), but is the best method for getting fertilizer to the media for root utilization when needed.

For dry fertilizer application, controlled-release fertilizers are the best delivery system.

Program monitoring:

• Soil test at least every three years
• Flow-through test every month for container stock
• Foliar test as needed, usually mid-June
• Water test as needed, at least for pH and EC

Source: Ohio State University Extension