The question of whether to mow or fertilize first is a common dilemma for homeowners seeking a lush, healthy lawn. Incorrect timing can lead to wasted fertilizer, uneven growth, or even damage to the turf. Understanding the proper sequence ensures the grass receives the full benefit of the applied nutrients, promoting strong root development and a vibrant green color.
The Correct Timing for Fertilization
You should always mow your lawn before applying fertilizer. This sequence ensures the product reaches the soil and the root system effectively.
The ideal timeline involves mowing one or two days before fertilization. This brief waiting period allows the grass to recover from the stress of being cut, reducing susceptibility to fertilizer burn.
For granular fertilizers, mowing first removes the excess grass length that would otherwise trap the pellets in the turf canopy. Liquid fertilizers also benefit from shorter blades, which allow for more uniform coverage and a clearer path to the soil surface.
Why Mowing First Is Essential
Mowing the lawn before fertilizing prepares the turf to best utilize the applied nutrients through mechanical and biological mechanisms.
Mechanical Benefits
Cutting the grass reduces the physical barrier created by long blades. This allows granular pellets to fall directly onto the soil surface, which is the necessary step before they can be activated and absorbed by the roots.
If long blades catch the granules, the fertilizer can be wasted or cause localized over-fertilization, leading to spots of burning.
Biological Benefits
The act of mowing initiates a plant response focused on wound repair. Applying a nitrogen-heavy fertilizer immediately after a cut can exacerbate this stress, potentially leading to leaf tip burn.
By waiting a day or two, the grass begins its recovery and is ready to direct incoming nutrients toward deeper root growth and sustained development.
Post-Fertilization Steps for Success
Following the application of fertilizer, certain steps must be taken to ensure the nutrients are properly activated and absorbed by the root system. The most important post-application task is watering, especially when using granular fertilizers.
The solid pellets require moisture to break down and dissolve into the soil solution, making the nutrients available for root uptake. Aim to apply about half an inch to one full inch of water to soak the fertilizer into the upper layer of the soil.
This watering step activates the fertilizer and helps prevent nitrogen burn by diluting the concentrated salts away from the grass blades.
After watering, the lawn needs a waiting period before the next mow to allow the product to settle and penetrate. For granular products, wait at least 24 to 48 hours, or until the fertilizer has been watered in and the grass is completely dry. Mowing too soon risks scattering undissolved granules, which reduces the treatment’s effectiveness and can lead to uneven growth patterns.