When to Fertilize Your Lawn Through the Seasons for the Healthiest Grass

2024-08-08
When to Fertilize Your Lawn Through the Seasons for the Healthiest Grass

Fertilizer can give a lawn a boost, but knowing when to fertilize your lawn is vital for your grass to gain the full benefit of those vital nutrients. Feeding your turf at the right times through the seasons can result in fewer lawn weeds, less insect and disease issues, and better tolerance of drought and temperature extremes. This guide will help you build a simple fertilizer calendar that will help you save money and time, while giving you lush, healthy grass.

Start with a Soil Test

It is essential to know the nutrient composition of your soil before applying lawn fertilizer. Overfertilization is a common problem that has far-reaching adverse environmental effects, from groundwater contamination to degradation of waterways. Take time to perform a soil test through a reputable testing lab. Your local extension service can be a resource, and there are also several online soil testing companies.

A soil test will reveal levels of phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg), along with soil pH. Turf grasses use large quantities of nitrogen (N) for growth, but there isn’t a reliable test for this nutrient. Timely application of a lawn fertilizer with the N-P-K ratio indicated by the soil test will supply ample nitrogen. Plan to have the soil tested every two or three years to maintain an accurate picture of your lawn’s nutrient needs.

Know Your Grass

The type of grass that makes up your lawn helps determine fertilizer timing by season. Lawn grass is divided into two groups: cool-season grasses and warm-season grasses:

Homeowners in moderate coastal climates and the lower Midwest might be growing cool-season or warm-season grass. But in general, if winter brings snow to your landscape, you’re probably growing cool-season grass, such as Kentucky bluegrass or tall fescue. These grasses have a soft texture and stay green late into the fall.

If you live in a region that doesn’t receive snow in the winter, your lawn is probably a warm-season grass, such as bermudagrass, St. Augustinegrass, or zoysiagrass. These grasses have a coarse texture and quickly turn brown in cool weather.

When to Fertilize Cool-Season Lawns

Only fertilize a lawn when it is actively growing. Cool-season lawns vigorously expand their roots and blades in spring and fall, making these the best times to fertilize them.

Spring

Apply a balanced lawn fertilizer as indicated by the soil test in spring after the second mowing. Use a slow-release fertilizer to limit excess growth and provide nutrients over the course of several weeks. Apply up to 1 pound of slow-release fertilizer per 1,000 square feet in spring.

Word of caution: avoid overfertilizing in the spring. A sudden influx of nitrogen will cause grass to grow fast at the expense of root health. Too much nitrogen in the spring can create a weak root system that isn’t able to withstand the heat and drought in summer.

Summer

Apply little or no fertilizer in summer. The lawn grows more slowly in summer and uses fewer nutrients. Drought and heat might push the lawn into dormancy. No amount of fertilizer will green up a dormant lawn. Fertilizing a heat-stressed or drought-stressed lawn can multiply the problem as fertilizer spurs the grass to grow, but it may not have adequate moisture to do so.

Fall

Cool-season grasses benefit most from fertilizer applied in the fall. Fertilizing helps the grass recover from the stress of summer by providing the necessary nutrients for root and shoot growth. Fertilizing in fall leads to a denser carpet of turf and prepares the grass for winter. Apply about 1 pound of nitrogen-containing fertilizer per 1,000 square feet two or three times at one-month intervals beginning in early fall.

Winter

Do not fertilize a cool-season lawn in winter. It is dormant and not actively growing. Fertilizing in winter is wasteful and harmful to the turf.

When to Fertilize Warm-Season Lawns

 Always fertilize a warm-season lawn when it is actively growing. Generally, warm-season grasses grow when nighttime temperatures are above 70°F. The maintenance requirements and overall appearance of warm-season grasses are greatly influenced by the amount of fertilizer applied over the course of a year.

More fertilizer will likely bring about a higher quality lawn, but along with that carpet-like appearance comes higher water demands, more mowing, and in some cases, a greater susceptibility to pests and diseases. The recommendations shared here are for a low-maintenance lawn; it will look great but not demand a lot of extra attention.

Spring

Wait to fertilize in spring until after you have mowed the grass two or three times. Fertilizing a warm-season lawn too early is a surefire way to cause turf dieback and lawn trouble for months ahead. Bermudagrass, St. Augustinegrass, and zoysiagrass do well with a spring application of 1 pound of fertilizer per 1,000 square feet. Don’t fertilize centipedegrass and buffalograss in spring; they grow best with just one fertilizer application in the fall.

Summer

Fuel the rampant summer growth of warm-season grass by fertilizing Bermudagrass, St. Augustinegrass, and zoysiagrass with an additional pound of slow-release nitrogen-containing fertilizer per 1,000 square feet. Choose a slow-release formula to avoid surges of growth. Just like in spring, don’t fertilize centipedegrass and buffalograss.

Summer fertilizer is not essential for good growth; warm-season grasses can easily be maintained with a spring and fall fertilizer application. Fertilizing in summer will result in a greener lawn, provided rainfall is adequate. If drought conditions develop and warm-season grass goes dormant in summer, do not fertilize. Fertilizing dormant grass can kill the turf.

Fall

Fall is the most beneficial time to fertilize warm-season lawns. If you can only fertilize your turf once a year, do it in the fall. Applying lawn fertilizer in fall spurs warm-season grasses to increase density, which helps them resist winter weeds. Fertilizing in the fall also improves the color of the grass and prepares the turf for strong growth in spring.

Make a fall application of 1 pound of fertilizer per 1,000 square feet of lawn at least six weeks before frost is expected. The turf needs this lead time to absorb the nutrients before growth ceases in winter. Use a water-soluble or quick-access form of nitrogen.

Winter

Do not fertilize a warm-season lawn in winter.

Related Article

12 Unique Succulents to Set Your Houseplant Collection Apart

12 Unique Succulents to Set Your Houseplant Collection Apart

These 12 stunning and unique succulent varieties will add excitement to your indoor garden.
5 Must-Know Tips for Designing Moon Gardens That Shine at Night

5 Must-Know Tips for Designing Moon Gardens That Shine at Night

Moon gardens bring a touch of magic to home landscapes. Get expert advice on safety considerations, plants, lighting, and decor for designing your own outdoor space to enjoy after dark.
21 Xeriscape Plants for the Water-Wise Garden

21 Xeriscape Plants for the Water-Wise Garden

Create a beautiful landscape with these xeriscape plants that need little water and are low maintenance too.
How to Stop Birds from Flying into Windows

How to Stop Birds from Flying into Windows

Window strikes are common and deadly for wild birds, especially in mating and migrating seasons. Here's how to stop birds from flying into windows.
How to Make A Succulent Tower Planter

How to Make A Succulent Tower Planter

Build a DIY tiered planter that overflows with delightful succulents, adding height and beauty to your garden.
How to Create a Stunning Rose Arch Covered with Flowers

How to Create a Stunning Rose Arch Covered with Flowers

Grow a soaring rose arch with these pro tips on choosing, planting, pruning, and training roses onto an arched trellis.
What Is Rooting Hormone? Plus How to Use It to Propagate Your Plants

What Is Rooting Hormone? Plus How to Use It to Propagate Your Plants

Rooting hormone boosts the success of growing new plants from cuttings. Here's how to use it to propagate your plants more effectively.
How to Plant and Grow 'Popstars' Phlox

How to Plant and Grow 'Popstars' Phlox

Annual 'Popstars' Phlox looks like floral fireworks in the garden. They bloom in bright colors all summer long and are super easy to grow.
11 Boxwood Alternatives to Add Evergreen Elegance to Your Landscape

11 Boxwood Alternatives to Add Evergreen Elegance to Your Landscape

When you need a boxwood alternative in your landscape, these 11 evergreen plants are excellent solutions.
10 Stunning Types of Magnolia Trees and Shrubs for Your Landscape

10 Stunning Types of Magnolia Trees and Shrubs for Your Landscape

There is a type of magnolia tree or shrub for every landscape. Use this guide to choose the best magnolia for your garden.
16 Pretty and Simple Combinations of Window Box Flowers for Shade

16 Pretty and Simple Combinations of Window Box Flowers for Shade

Here are 16 beautiful and easy-care combinations of window box flowers for shade to add color wherever you need it.
Florida Weave for Tomatoes: 7 Steps to Perfectly Trellis Your Plants

Florida Weave for Tomatoes: 7 Steps to Perfectly Trellis Your Plants

Learn the benefits of using the Florida weave for tomatoes and follow our step-by-step guide to make your own DIY tomato trellis with this budget-friendly method.
How to Propagate Lavender to Make More Plants for Free

How to Propagate Lavender to Make More Plants for Free

Learn how to propagate lavender with this step-by-step guide using two simple plant propagation techniques.
How to Get Rid of Mushrooms in Your Yard: 4 Natural Solutions

How to Get Rid of Mushrooms in Your Yard: 4 Natural Solutions

Find out how to get rid of mushrooms in the yard by understanding why they are popping up. Then solve the problem naturally with this simple guide.
How Often—and How Long—You Should Water Your Grass

How Often—and How Long—You Should Water Your Grass

Whether you water manually or you have an underground sprinkler system, follow our tips for how long and how often to water your grass to keep from overwatering your lawn.
Peach Tree Diseases and Pests

Peach Tree Diseases and Pests

Here's what you need to know about common peach tree diseases and pests and how to fight them.
How to Stop Rabbits from Eating Plants in Your Garden

How to Stop Rabbits from Eating Plants in Your Garden

Bunnies may be cute, but they can also be garden saboteurs. Here's how to stop rabbits from munching on your flowers, shrubs, and vegetables.
17 Deer-Resistant Shade Plants That Will Brighten Up Your Garden

17 Deer-Resistant Shade Plants That Will Brighten Up Your Garden

These pretty perennials and shrubs are deer-resistant shade plants, and most of them bloom for added color.
11 Ways to Create Low-Maintenance Landscaping Around Your Home

11 Ways to Create Low-Maintenance Landscaping Around Your Home

These low-maintenance landscaping tips will help you spend less time doing yardwork and more time enjoying your garden.
Does Gardening by the Moon Really Work? Here's What Experts Say

Does Gardening by the Moon Really Work? Here's What Experts Say

Many gardeners believe gardening by the moon can help plants grow better. Here's what experts and research reveal about following lunar calendars for timing gardening tasks.