3. Fertilize?
When soils are adequate, only newly established and young lawns need fertilizer and, even then, only nitrogen—phosphorus and potassium are seldom needed, unless indicated by a soil test. The guideline of applying 2–4 pounds of nitrogen fertilizer per 1,000 square feet of lawn has been revised to one-quarter to one-half that amount. Basically, lawns need only one or two applications per year at half the labeled application rate.
Lawns 10 years and older store necessary nutrients and may never need fertilizer. Grass clippings are free fertilizer—if these are returned to the lawn with a mulching mower, chances are, additional fertilizer will not be needed.
When to Fertilize: Contrary to popular belief and common practice, spring is not the best time to fertilize a lawn. At that time, nitrogen will encourage top growth at the expense of roots and will promote germination of weed seeds. If and when fertilizer is applied, ideally it should be done only once or twice a year in late August or September. This approach provides fertilizer when the grass can best utilize it, not when it is likely to run off into waterways (always sweep fertilizer back onto the lawn from sidewalks and driveways). Fertilizer should never be applied to frozen or saturated soils, or in advance of expected heavy rain. |
|
