Excessive fertilization is detrimental to your lawn, wastes money, causes pest problems and is bad for the environment. Knowing how and when to fertilize your yard is essential in creating a healthy lawn.
Step 1: Test your soil every three to five years. Gather two cups worth of soil from various parts of the yard. Seal it in a bag and drop it off at your local county extension office. Within a few weeks they will provide you with a detailed analysis of the soil and let you know what nutrients and amendments you should add to your lawn.
Step 2: Know your fertilizer. Quick-release fertilizer is water-soluble and will release nutrients into the soil immediately. Too much of a good thing will burn the grass and contaminate the groundwater. Time-release fertilizers do not dissolve in water. Instead, they break down over an extended period of time, making nutrients available to grasses on an as-needed basis. Unfortunately, water-insoluble fertilizers are somewhat unpredictable and are ineffective in the colder temperatures of early spring and late fall.
Step 3: Do the math. Know how much nitrogen your lawn needs and calculate the number of times you should fertilize each year. Tall fescue requires 1-4 pounds of nitrogen per 1000 square feet each year. Zoysia and buffalo grasses require 1-2 pounds, and blue grass requires 2-5 pounds. Never apply more than 1 pound of nitrogen per 1000 square feet at a time. The numbers on a bag of fertilizer represent the percentage by weight of each nutrient. A 20-pound bag of fertilizer labeled 20-5-10 contains 4 pounds of nitrogen (20 lbs x 20% = 4). More nitrogen equals more mowing; too much nitrogen equals no mowing at all.
Step 4: Fescue, bluegrass and rye grass do best with a fall application of nitrogen. September is by far the best month to fertilize. Spring application of other nutrients is beneficial, but applying nitrogen too early in the season will compromise the root structure of the grass, making the lawn more susceptible to drought and disease. Bermuda, zoysia and buffalo grasses are considered warm-weather grasses. They do best when fertilized in late spring or early summer. No matter what type of grass you have, fertilize only when the grass is growing.
Now choose your fertilizer, set your schedule and take a slow walk through the yard, dropping just the right amount of nutrients along the way.