How Lawn Fertilization Can Prevent Weeds & Pests

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Lawn fertilization is essential for a healthy and vibrant lawn. It helps to keep grass lush, green, and strong, but fertilizers can also be used as an effective way to prevent weeds and pests from taking hold of your Kansas City lawn. Fertilizers contain both chemical and organic components that work together to deter these unwanted visitors from invading your yard. In this article, we will discuss the various elements of fertilizers and how they help protect against weeds and pests!

What Is In Fertilizer?

chemicals and nutrients for the soil

Lawn fertilizers contain many different nutrients and minerals in order to promote healthy grass growth. Nitrogen, phosphorus, and potassium are the main components of fertilizers, and they are referred to as the NPK ratio. These macronutrients are essential for healthy grass growth, with each nutrient playing a different role in improving the soil to make it ideal for your lawn to thrive.

  • Nitrogen (N) - This ingredient gives your grass a boost of energy and color by aiding in the production of proteins and chlorophyll. Nitrogen is considered the most important nutrient found in fertilizers and soil.
  • Phosphorus (P) - The second important nutrient found in fertilizers is phosphorus, which plays a key role in healthy root development. Phosphorus is also used to store energy and nutrition obtained during photosynthesis.
  • Potassium (K) - Last, but just as important, is potassium. This nutrient helps stop the spread of disease, and it prevents stress from drought and winter weather by thickening cell walls within grass blades.

In addition to these macronutrients, there may also be a combination of certain micronutrients to help make the soil more fertile and ready to sprout grass. Elements such as calcium, magnesium, sulfur, iron, zinc, and more may be present in your lawn fertilizer. These nutrients provide vital support for the grass growing in your lawn to stay strong in defense against both weeds and pests.

Do Fertilizers Contain Herbicides?

direct weed control sprayed onto a dandelion

You can find certain types of fertilizers that contain weed killer in them, which some lawn care enthusiasts appreciate for the convenience. These products are often referred to as "weed and feed" and can be applied to your lawn to both improve grass growth and stop weeds from growing. The fertilizing chemicals in a weed and feed product could be any range of NPK ratios depending on the season and need of your lawn. For example, early spring or starter products typically have a higher amount of nitrogen than any other nutrient in order to achieve lush growth quickly.

The most common herbicides in weed and feed are dicamba, mecoprop, and 2,4-D. These chemicals are considered post-emergent herbicides, meaning they target weeds that are already visible and growing in your lawn. A pre-emergent variety of weed and feed will typically include dithiopyr (commonly sold as "Dimension"), and it will help create a protective barrier across your lawn that prevents weed seedlings from ever emerging. Both varieties will include the NPK macronutrients to improve grass growth at the same time as these weed-killing efforts are being made.

It is important to note that weed and feed products target only broadleaf weeds, such as dandelion, chickweed, blue violet, etc. Grassy weeds like crabgrass or annual bluegrass will not be affected by the chemicals in weed and feed. For these grass-like weeds, you would need a non-selective herbicide that gets applied directly to emerged weeds. Only selective herbicides can be used in weed and feed because they will target broadleaf weeds without harming your grass, whereas non-selective herbicides do not differentiate between grassy weeds and the grass in your lawn.

Do Fertilizers Contain Pesticides?

Deer tick right next to a child outside

Fertilizers containing pesticides are not as common as weed and feed, and there are good reasons for that. While keeping pests away from your lawn is important to the health of your grass, pesticides/insecticides include more dangerous chemicals that need to be administered carefully. Applying too much pesticide to your lawn can be harmful to the rest of the vegetation in your yard, wildlife that visits your lawn, and even pets and children that like to lie out in the grass.

Some people do like to combine a mixture of pesticides and fertilizers to treat their lawns, but this is not advisable for a homeowner who is not extremely knowledgeable about the chemicals being used. The best advice is to call or consult with a professional lawn care company that has experience dealing with these products. Professional services can include separate applications of fertilizers, pesticides, and grub preventers to make sure that your lawn is protected and healthy in the safest way possible.

How Fertilized Lawns Deter Weeds & Pests

beautiful green lawn

Have you ever heard that the best defense is a good offense? This is definitely true when it comes to lawn care! Regardless of whether or not you apply herbicides and pesticides to your grass, a well-fertilized lawn is always the best way to prevent weeds and bugs. The NPK elements in the fertilizer will give your grass the nutrition it needs to be as strong and healthy as possible, and any weeds or pests that attempt to invade your lawn will have a more difficult time surviving. This is why fertilizing your lawn regularly is one of the most important steps for keeping weeds and bugs away from your yard!

The list below details some of the ways a well-fertilized lawn can keep out weeds and pests:

  • Thicker lawns crowd out weed growth.
  • Taller grass blocks sunlight from reaching young weeds.
  • Stronger roots make it difficult for weeds to take root in the soil.
  • Fertilization prevents standing water, which pests seek out.
  • Phosphorus fortifies cell walls of grass, strengthening them against pests.
  • Fertilizer stimulates new growth to repair damage from weeds and pests.
  • Fertilizers provide extra nutrients to replace what weeds steal.
  • Regular fertilization prevents poor grass health and vulnerability against weeds and pests.

When To Apply Fertilizer

Scaled Granular fertilizer example

It is important to know when to apply fertilizer in order to get the best results for grass growth. Generally speaking, fertilizer applications should occur at least twice a year; once during late early spring and again in early fall. Fertilizing earlier than these recommended dates can cause grass growth rates to become imbalanced, resulting in weak blades of grass that are vulnerable to weeds and pests. Mid-summer applications can also be done, but you have to make sure to use the right summer fertilizer that will not evaporate or provide too much nitrogen to the soil.

For the best defense against weeds and pests during fertilizer applications, call a professional lawn care company like Heartland! Our team has been combating lawn intruders in the Kansas City area for years, and we know how to keep your grass lush and green in the process. Call today for a free quote!