Fertilizer Spreaders: The Key to a Good Lawn

Proper fertilizer application is very important. A good fertilizer spreader is the key to efficient fertilizer use. Improper fertilizer application can lead to alternating strips of light and dark green grass. Too much fertilizer can burn or increase susceptibility to disease damage. Too little can lead to a thin, weak lawn with abundant weeds. There are basically two types of dry fertilizer spreaders that are used on home lawns and gardens. These are the gravity spreader and the centrifugal spreader.

The gravity spreader is also know as a drop spreader. It meters the fertilizer through ports along the entire width at the bottom of the hopper. The size of opening is varied by an adjustable shutter. A rotating shaft along the bottom of the hopper helps control and feed the fertilizer into the openings. Gravity spreaders are accurate if property maintained and are close to the ground so there is little or no drift. The centrifugal, or cyclone spreader, uses spinners to distribute the fertilizer metered onto them through a gate on the bottom of the hopper.

Application rates vary more widely and are dependent on gate opening, spinner speed, and how well the fertilizer flows. Cyclone spreaders cover a wide path, however, and are a much faster method of application. Their basic disadvantage is less accuracy. Some fertilizers list on the bag the necessary settings for popular spreaders. If there are no settings indicated, it may be necessary to calibrate a spreader for the fertilizer being used.

Most recommendations are made for the amount of fertilizer being applied to 1,000 square feet. By multiplying the wheel circumference by the width of hopper opening you can determine the area covered by one wheel revolution of a drop spreader. Divide this number into 100 to determine how many wheel revolutions are necessary to cover 100 square feet. Be sure all measurements have been made in feet or fraction thereof.

Choose a trial setting and add to the hopper 1-10 of the fertilizer (by weight) necessary for application to 1,000 square feet. Place drop cloth beneath the spreader and raise the spreader drive wheel off the floor slightly. Rotate the wheel the number of times calculated. If all the fertilizer has moved through the spreader in the revolutions indicated, the setting is proper. If not, it may be necessary to repeat the procedure at a new setting either opening or closing the shutter a little more as indicated.

Fill the lawn spreader on a walk or drive, not on the lawn, and be certain the spreader is closed. If filled on a lawn area, too much fertilizer may drop out, causing a burned strip. Avoid skips or missed streaks. Gravity types require a slight overlapping of wheel tracks. For most uniform patterns, operate spreaders at one-half the recommended amount and make two trips over the lawn at right angles. Always push a gravity spreader forward. Pulling it backwards may result in excessive release.

Maintain a uniform pace while spreading materials and avoid the use of centrifugal spreaders on windy days. Shut spreaders while making sharp turns. Proper care of spreaders after use is also important to keep them functional and accurate. Never leave fertilizer in a spreader. The fertilizer is highly corrosive and can cause rusting. Thoroughly clean out all materials after use. If hosed out after use, allow to dry thoroughly and then apply a thin coat of oil to the bottom surfaces to minimize rusting. Store with shutter or gate fully open.

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