When to Fertilize a Lawn

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When your lawn is looking a little shabby, you may be tempted to throw some fertilizer on it. But when, how, and at what time you fertilize your lawn requires some careful consideration.

The best time of day to fertilize a lawn is morning because that's when the temperature is cooler and the grass is moist with dew. Heat and dryness are your enemies when fertilizing your lawn. Even without hot temperatures, applying chemical fertilizers to grass exposes it to the danger of burning. Plus fertilizer should be watered immediately into the soil, and this task is easier to perform on a lawn already moist. The exception is with "weed and feed" products, which you don't want to water in immediately: You want the herbicidal component to maintain contact with the weeds for a period of time.

Should You Fertilize Your Lawn?

There are many things to consider before answering this question. Not everyone's goals and circumstances are the same. So the answer will vary from individual to individual.

If you want a great-looking lawn, and if you have the time, energy, and money to achieve that objective, then the answer is unequivocally yes. Proper fertilization is one factor that can make one lawn in the neighborhood stand out above the rest. Which brings us to the question, How often should you fertilize your lawn? Because, if you truly care about showcasing your lawn, you will want to fertilize it more than someone who is content with a patchy lawn. For the ultimate manicured lawn, you should fertilize it two or three times per year.

But not everyone needs (or even wants) a lush lawn. There are homeowners who value low maintenance over having the showiest lawn on the block. There are some homeowners who are organic gardeners, who shy away from using chemical fertilizers. Homemade compost can be applied to a lawn, instead, but there is work involved in making compost. Gardeners may value what compost is available too highly to waste it on lawns rather than on vegetable gardens. And there are some who simply hold lawns in low esteem; for them, grass-covered areas are utilitarian, functioning merely as spaces for walking from point A to point B in the landscape.

If any of those descriptions fit you, the good news is that grass can perform reasonably well for years without being babied with fertilizer. You may have to overseed your lawn occasionally as compensation, but this will still mean less work and less expense in the long run. Just don't expect to have the best-looking lawn in the neighborhood.

When to Fertilize Your Lawn

What time of year is best to fertilize your lawn depends on what type of grass you have, cool-season or warm-season. This is because the best time to fertilize is the period when the grass in question is growing most actively, and this period is different for cool-season grasses than it is for warm-season grasses. Nonetheless, there's no one "right" fertilizer schedule. Different people have success doing it in slightly different ways. All that can be suggested is a typical schedule favored by many.

Fertilizing Cool-Season Grasses

True to their name, cool-season grasses, which are used in the North, grow most actively when the weather is cool: fall and spring. Keeping this in mind, if you want to go all-out in your lawn care, you will fertilize three times:

  1. A typical schedule begins with applying a winterizing fertilizer in late fall. This fertilizer will not only help the grass get through winter in good shape but also furnish the nutrients that will get it off to a good start when it begins growing next spring. Indeed, if you've winterized your lawn, there is no need to fertilize in early spring,
  2. But do take advantage of the lawn's active growth in late spring to fertilize it a second time. This is the feeding that will give your grass the optimal health it will need to endure the challenges posed by summer.
  3. Fertilize a third time in late summer, providing the nutrients your grass will draw on during its autumn growth spurt.

Fertilizing Warm-Season Grasses

Warm-season grasses are used in the South. They grow most actively when the weather is warm. A typical schedule, consisting of two feedings, would run as follows:

  1. Make your first application in late spring or early summer, which is when the temperature (and, along with it, your warm-season grass) starts to ramp up.
  2. Your grass will still be growing actively in late summer and into the fall. Take advantage of this fact by applying fertilizer for a second time in late summer. This feeding will also give your grass the boost it needs to recover from whatever damage it endured during the first part of summer.  

When Not to Fertilize Your Lawn

Don't apply fertilizer when a heavy rainstorm is in the forecast. A downpour may wash the fertilizer away. But if you're expecting a moderate amount of rain to come and to fall steadily upon the earth, this is an ideal time to fertilize: It will save you from having to water the fertilizer in, yourself.

Since heat and dryness are your enemies when fertilizing a lawn, avoid applying fertilizer to your grass during periods of severe drought. Your grass is stressed at such times, increasing the likelihood that a chemical fertilizer will burn it.