The Best Time of Year to Fertilize Your Lawn

When to apply grass fertilizer is as simple as the why, which is an important piece of the answer to the question, “what is the best season to apply fertilizer?”

The season depends a little on the reason: is your soil in good health? Are you hoping to prepare vulnerable grasses for harsh temperatures? Is your soil’s pH imbalanced?

The best time to apply fertilizer depends on several factors unique to your climate, grass type, and soil conditions, and some lawns require multiple applications throughout the year. We’ll break down the purpose of fertilizing grass, the best time to fertilize a lawn, and how to do it when you're ready.

First things first: do I need to fertilize my lawn? 

Fertilizing a lawn can provide several benefits, beginning with your soil health. Fertilizers are heavy in nitrogen and often other micronutrients, like potassium and phosphorus. When your lawn’s nutrients become depleted after a long growing season or a harsh winter, fertilizer can restore the soil’s balance of nitrogen and carbon to give plants their best chance to thrive.

When deciding whether you need to fertilize your lawn this year, consider the health of your lawn. If your grass is showing signs of poor root health, fertilizing can help grass build strong roots while grasses are still actively growing. If you’ve recently dealt with a grub problem, or if your grasses are dried, brown, brittle, or not absorbing nutrients or water well, Fertilization can help condition the soil and rebuild stronger roots.

If your grass has had a healthy growing season this year, is green, thick, and mostly weed-free, you might only need to fertilize twice this year, in the Spring and Fall. This is especially true if you don’t need to reseed your lawn this year.

Most lawns require reseeding annually, to fill in thinning or bare spots, and to help the lawn recover from heavy use and compaction throughout the warmer months. If you plan to reseed this year, fertilizer can help new seeds emerge with the nutrients they need. Fertilization can also be helpful a few times throughout the year to help control weeds and nurture growing grass.

What is the best time of year to fertilize your lawn? 

The best time for lawn fertilizer depends partly on the type of grass seed you’re using. If you’re using cool season grasses (common for New Jersey lawns), Fall and Spring are the best times of year to fertilize lawns. The best time to fertilize lawns with warm season grasses is late Spring. However, some lawns will need fertilizer reapplied throughout the growing season.

If you’re not sure what type of grass you’re growing, New Jersey lawns should be fertilized in the Fall, and probably again in the Spring, at a minimum. Read more on the best types of grass seed for New Jersey lawns here.

The reason for this is simple: Fall is a peak growing season for cool-season grasses, and Spring for warm-season grasses. Fertilization works for your grass when the grasses are actively establishing their roots. Introducing young grass roots to rich soil helps them grow deeper, reach and absorb more nutrients from soil and water, and anchor stronger, healthier grass blades later.

The best time to put fertilizer on lawns also depends on your lawn’s health. If your lawn has been struggling this year, it might be a good idea to fertilize multiple times throughout the year. If you’re introducing a new type of grass seed, switching to fully organic growing, or have poor soil health, applying fertilizer in both Fall and Spring may help establish healthier grass and grass roots. Some lawns require up to 6 applications per year, depending on the health of your soil and growing grass.

Fall and Spring are also the best time to apply grass seed to your lawn, which is why they’re great times to apply fertilizer. We’ll explain more about that below.

How often should I fertilize my lawn? 

Understanding your soil health can be a great way to determine how often you need to fertilize your lawn. Most homeowners need to reseed at least annually, which is why the rule of thumb is that you’d apply fertilizer around the same time.

However, your grass health will indicate whether your lawn needs a little more help reaching nutrients and getting established. Signs that your lawn might need fertilizer are those we listed above: poor root health, dry, brown, or brittle grasses, or a recent pest or weed infestation. Lawns with these challenges require more frequent fertilizer application.

If you’re not sure whether your soil’s pH is imbalanced or whether the soil has the right combination of nutrients, request a soil health test from your local lawn care company. Understanding the profile of your soil can help determine whether you need to fertilize more often.

How and when to fertilize lawns in NJ

Once you’ve settled on the best season to fertilize your lawn and you’ve chosen your preferred fertilizer, it’s helpful to fertilize in conjunction with aeration and reseeding services.

Most lawns need aeration annually after a long season of use and compaction. Aeration is a great precursor for overseeding in the fall because it loosens soil for root growth and helps seeds begin germination more deep within the soil. Fertilization is the next step after reseeding.

Caring for your lawn with this three-step approach gives your lawn the best chance of establishing healthy roots, protecting seeds from harsh winter weather, and replenishing areas that are currently bare. We offer a variety of Fall lawn care services for NJ lawns, and each begins with this three-step foundation.

If you’re applying on your own, you can do so immediately after aerating and reseeding. Even if you’re not reseeding this year, aeration is a good first step because it’ll allow the nutrients in the fertilizer to penetrate the soil surface more deeply.

Do not apply fertilizer during periods of drought or heavy rainfall. Be careful waiting too long to apply fertilizer in the Fall, as it can harden your turf and make it more susceptible to cold weather damage.

When you’re ready to apply, read and follow the directions on the packaging carefully. Apply fertilizer as directed. To avoid creating a striping pattern on your lawn, apply half of the fertilizer in one direction, and the other half perpendicular to that. Water your lawn according to the instructions on the fertilizer packaging, and do not apply weed killer at the same time if possible.

Green Roots knows the best time to apply fertilizer

Don’t feel like going through the hassle of applying your own fertilizer? Need help deciding what type of fertilizer is best for your lawn? Ready for a soil health test?

If any of these sounds like you, leave your lawn’s care to us. Our experts can assess your lawn and effectively apply the right fertilizer, at the right time and frequency. Many of our products are also eco-friendly! 

To get your free estimate or soil health test, get in touch with us today. Or, check out our Spring lawn care packages to decide which services are right for you. Happy growing!