Lawn Fertilizing Tips

Lawn grass

Lawns require over 18 nutrients to grow and provide a lush forest of green blades. Nearly all, save three, of these nutrients are provided by the natural processes that occur in the soil. Three of the required nutrients, nitrogen, phosphorus and potassium, are not produced in the soil in sufficient amounts to support optimal lawn performance and are supplemented in various fertilizer formulations.

Timing of Application

The three best times of year to fertilize grass lawns are spring, late summer and fall, and even though the average person would guess that that spring is always best, it is not necessarily so. Heavy spring feeding tends to make the blades grow lush and green but shortchanges root development, making for weakened plants. When the heat of summer comes, the roots are not in a good position to absorb the stress, and the grass loses some of its good looks. A combination of spring, summer and fall feedings makes for the best of both worlds.

Needed Nutrients and Absorption

A good fertilizer regimen for green, actively growing lawns is between 2 to 4 pounds of a nitrogen-rich formula for every 1,000 square feet of grassy area per year. If you use a quick-release formula, this will likely mean 3 to 5 applications throughout the growing seasons for your grass varietal and climate. If using a slow-release formula, this may mean only one and at the most two applications per year. In each case consult the manufacturer's application instructions to determine dosing. An additional nutrient boost can come from leaving grass clippings on the lawn after mowing in lieu of discarding them. The clippings will decompose and act as a natural fertilizer to the roots.

Fertilizer Application Methods

There are many automatic spreaders or casters on the market to make fertilizing easy. If using dry fertilizer, invest in a drop or broadcast spreader. Drop spreaders are good for smaller areas of lawn while broadcast spreaders are better for large expanses. Calibrate the rate of your spreader to the fertilizer you are using by the application tables on the reverse of the packaging. Liquid lawn fertilizer is also common and convenient and is considered just as effective as the dry method. With liquid fertilizer you mix the fertilizer with water and can apply them both at the same time, combining two necessary steps---watering and fertilizing---into one.

References

• This Old House Video Guide to Fertilizing Lawns
• Univeristy of Minnesota Extension white paper on Fertilizing Lawns