9 Times You Should Never Fertilize Your Lawn to Avoid Ruining It

If you’ve browsed the fertilizer aisle lately, you know these products can be a significant investment. To get the most bang for your buck and a healthy response from your lawn, it is key to apply fertilizer at the right time.

Even though activity-packed schedules and weather make it challenging to time fertilizer application correctly, there are certain instances when you should never apply fertilizer. Avoid these timing pitfalls by following a few best-practice fertilizer tips for a lush, healthy lawn and surrounding ecosystem.

Fertilize Only During Active Growth

Before digging into the details around when not to fertilize, it is essential to know one overarching rule: only fertilize your lawn when it is actively growing. Why? Because living and growing roots or foliage must absorb the fertilizer for the plant to reap the benefits of the product.

There are several additional factors to consider when timing a fertilizer application, but active growth is a key component of the equation. If you are mowing your lawn regularly, it is actively growing and likely prime time for a fertilizer application.

When You Should Not Fertilize Grass

Conflicting advice abounds regarding fertilizer timing. However, the appearance of your lawn or a calendar date should not be what drives your decision about fertilizer timing. These factors often lead to damaged turf or wasted fertilizer.

Hold off on fertilizing your lawn in these situations:

1. Grass Is Wet

When the grass is wet, the fertilizer granules stick to the grass blades, burning and discoloring them. Avoid fertilizing in the morning when the grass is wet with dew. Instead, fertilize in the evening when grass is cool and dry.

2. In a Drought

Unless you are committed to regularly irrigating your lawn, drought conditions are one of the worst times to fertilize. Drought-stressed grass is putting all its resources into staying alive. Fertilizing at this time will further stretch the plants’ resources, triggering them to divert life-giving moisture to capturing the newly available nutrients at the expense of shoot and root health. 

3. Extreme Heat

Turfgrass thrives when daytime temperatures are between 60-80°F. When the mercury climbs above 90°F for several days, growth slows and grass plants reserve resources for sustaining life. Fertilizing during extreme heat can be harmful for grasses. The turf will attempt to take up the nutrients, often expending energy that can’t be quickly replaced. The result is a partially dead lawn. Fertilize when daytime highs are at seasonal levels.

4. Summer Dormancy

High temperatures combined with a lack of moisture send lawns into summer dormancy. This natural phenomenon is a protection tactic against tough growing conditions. Leaf growth stops, and the grass turns brown and dry. The crown and roots are still alive and will push up new stems as soon as conditions improve.

Fertilizing during summer dormancy can spur grass to emerge from dormancy when conditions are not ideal for it to thrive. Remember, grass must be actively growing to use fertilizer well. Delay fertilizing until the grass greens up naturally after summer dormancy. 

5. Winter Dormancy

Just like summer dormancy, winter dormancy is a natural, protective response of the grass plants to adverse environmental conditions—cold conditions send turf into winter dormancy. Fertilizing in winter is ineffective as the grass is not growing and will not take up the nutrients. If moisture is present during winter dormancy, the fertilizer will likely run off with rain or snow melt, potentially polluting the surrounding environment.

6. Forecast of Heavy Rain

Fertilizing before heavy rain is useless at best and harmful at worst. A driving rain within hours after fertilizing may push the product through the soil profile, out of reach of the plant roots, or remove it off the soil surface in the water runoff. A light rain is welcome after a fertilizer application, but an intense storm will likely wash away the product and pollute nearby waterways.

7. No Watering After Fertilizer Application

If there is no immediate rain in the forecast, and you don’t have time to water fertilizer into the soil right after spreading it, fertilize another day. Fertilizer pellets left on grass blades after application will burn the turf, causing discolored patches and killing it in some cases.

After applying fertilizer, water your lawn gently with a sprinkler or irrigation system to settle the product onto the soil surface. Soon, moisture will break down the granules, and the nutrients will be absorbed by the roots. 

8. Disease or Pest Issues

Fertilizer isn’t a cure-all for lawn disease; on the contrary, fertilizer can amplify the problem. Positively identify the cause of the pest or disease infestation and take proper steps to treat it before considering a fertilizer application. 

9. Without Taking a Soil Test

Don't guess, soil test, because more is not better when it comes to lawn fertilizer. Overdoing the fertilizer causes grass to grow too fast, making it more susceptible to a host of pests and diseases. Test your soil every three years or so and follow the test recommendations for your fertilizer formulation.