Smart Yard, Healthy Gulf


I've never fertilized my lawn. Are you telling me I should start?

If you haven't fertilized before and are satisfied with your lawn, then by all means, continue to not fertilize. However, if you do consider fertilizing then knowing what type of grass you have is essential in determining if annual fertilizing is necessary. Some grasses require little care other than regular mowing once they are established. Some common grasses in coastal Alabama and Mississippi such as centipedegrass or carpetgrass require little or no extra fertilizer. Healthy grass with deep roots and tight foliage cover does not need "constant attention." This is true for any warm season grass species in Alabama and Mississippi. The deep root system allows the grass to experience summer dormancy (brown tops) in droughty years without dying.


Which grasses need annual fertilizing?

Bermudagrass, St. Augustine and zoysiagrass need more nitrogen than others. Mowing three to four times per month and mulching the clippings back into the lawn provides some of this nutrient. However, these grow their best with the addition of one pound (ANNUAL max) of nitrogen per 1000 square feet. You will have a healthy bermudagrass, St. Augustine or zoysiagrass lawn with just one or two nitrogen fertilizer applications per year. A healthy, established lawn doesn't normally need extra phosphorus or potassium.

When should I fertilize?

As a general rule of thumb, you should only fertilize grass that is actively growing. Do not fertilize lawns in the spring until after the danger of frost is past. A good rule of thumb is to wait until after you've mowed your grass at least twice. Of course, there are always exceptions. Some communities may have established ordinances that prohibit the purchase and use of fertilizer during certain seasons, including the growing season. These ordinances overrule the recommendations due to the extreme effect they have on local ecosystems.

Why should I wait to fertilize?

Fertilizing grass that is not actively growing results in excess nutrients, like nitrogen and phosphorus, leaching into the ground water or running off the surface into local water bodies. Not only is this wasteful, it can also lead to harmful algal blooms that negatively affect ecosystems.

A harmful algal bloom is a high concentration of a toxin-producing algal species. The toxins of harmful algal blooms can cause fish kills, accumulate in shellfish where their consumption can cause human illness, and some even become air borne risks to human health.

What is the proper amount of fertilizer?

The best way to determine the right amount of fertilizer for your lawn is to get a soil test which tells the status of nutrients in your soil. Fertilizer and lime recommendations will be made specifically for your lawn. Contact your County Extension Agent for a soil sampling kit and an instruction sheet. Soil samples will be sent to the Soil Testing Laboratory at your state's Land-grant University for analysis. There is a nominal fee and you only need to test every two or three years.

Why can fertilizer be a problem for water bodies?

Excess nutrients that are not taken up by your lawn enter local water bodies and become food for algae in the water. When too much algae exist in the water, they eventually die and their remains settle at the bottom of the water body and get decomposed by bacteria. This decomposition uses up the dissolved oxygen in the water to the point that other marine animals have no oxygen to survive. Always clean up fertilizer from paved surfaces or use a deflector on your spreader to prevent fertilizing the pavement.

How should I maintain my lawn after I fertilize?

Always use a sharp blade when mowing your grass. The frequency of mowing depends on the growth rate of the grass. The best rule of thumb is to mow often enough that you never cut more than one-third of the leaf area per mowing. When you mow grass properly, it is not necessary to remove clippings for the health of the lawn. You will need to remove clippings if they are so thick the grass is not visible; then remove the clippings to allow the sun to reach the grass. If you remove lawn clippings, consider composting them.

Is it ok to put lawn clippings at the curb for trash pick up?

Lawn clippings are an on-site resource that adds nutrients back to your grass or to other planting areas in your yard; recycle them on-site. If you do trash your lawn clippings, always place clippings in bags or cans for trash pickup. Do not place a pile of clippings directly on the street or in a pile with other yard waste. Rain will easily wash them into storm drains and surface water where they decompose and release nutrients.

What can a Master Gardener volunteer do for me?

A Master Gardener volunteer can help you identify your grass type, assist you with your soil test and help you interpret the soil test results. They are trained in grass management and know where to find answers to help solve your problems. Master Gardeners offer unbiased, research-based information to answer your questions.

What is a state Extension program?

State Extension programs provide research-based information from the Land-grant/Sea-grant University. They offer educational programs and a wide variety of lawn and gardening resources to help you make informed decisions on managing all types of plants, including grass. Extension Agents train interested volunteers to become Master Gardeners.

What do extension programs in my area offer?

Extension programs offer resources and advice on how to best manage your lawn and garden.