City of St. Paul Park 

on the Mississippi

Lawn Fertilization

Tips for responsible lawn fertilization.

Proper supply of nutrients

Few soils have enough natural fertility to sustain good turf grass quality.  Fertilizer can provide essential nutrients to maintain optimum turf grass growth.  There are three elements usually applied as supplemental fertilizer--nitrogen (N), phosphorus (P), and potassium (K).  Of the three elements nitrogen (N) is the nutrient that most often needs to be supplemented.   

The main objective in applying fertilizer should be to add necessary nutrients in the required amounts and at the proper time to achieve good quality turf.  A healthy lawn is able to recover from insect and disease attacks.  It will compete better with weeds, thereby reducing the need for pesticides.

Soil Testing

A soil test will inform you of the amount of nitrogen and phosporus in your soil and the appropriate application rate.  Soil tests are available through the University of Minnesota or through private firms.

Applying Nitrogen to Your Lawn

The amount of nitrogen your lawn needs depends on what type of grass you have and how you maintain it. 

  • High-maintenance lawns often contain vigorous Kentucky bluegrass and tuf-type perennial rye grass varieties.  These lawns perform better with regular applications of water and fertilizer.
  • Low-maintenace lawns usually contain common types of bluegrass combined with a mixture of other grasses.  These lawns grow and spread more slowly than high-maintenance lawns without reuiring much extra water or nitrogen fertilizer.

Applying Phosphorus to Your Lawn

Starting January 1, 2005, fertilizers containing phosphorus cannot be used on lawns in Minnesota unless a soit test shows a need for phosphorus fertilization, or a new lawn is being established. 

Fertilizing your lawn

  1. Fill granular fertilizer spreaders on a hard surface where spills are easy to clean up.
  2. Never wash fertilizer spills into the street.
  3. Clean fertilizer spreaders or applicators over grassy areas to prevent runoff of fertilizer into the street.
  4. Close the gate on your fertilizer spreader when crossing hard surface areas.
  5. Sweep up any fertilizer on hard surfaces.

Applying fertilizer near a body of water

  1. Leave a buffer zone of unmanaged grasses or natural vegetation along a shoreline. 
  2. Use a drop spreader, it is more precise than a rotary spreader.
  3. Never apply fertilizer directly into surface water or on to frozen ground.
City of St. Paul Park, 600 Portland Avenue, St. Paul Park MN 55071