Does Cornmeal Kill Weeds?

Nov 10, 2023

When it comes to organic gardening and weed control, finding effective methods that are both safe for the environment and your plants can be a challenge. One natural solution that has gained popularity in recent years is cornmeal. In this article, we will explore the question - does cornmeal kill weeds? We will delve into the benefits of using cornmeal in organic gardening and provide you with valuable insights on its application.

The Science Behind Cornmeal Weed Control

Cornmeal, which is finely ground dried corn, contains properties that can help suppress and eliminate weeds in your garden. The primary mechanism behind cornmeal weed control is its ability to inhibit the growth of weed seeds by disrupting seed germination. This natural inhibition is due to the presence of a compound called allelopathic chemicals found in cornmeal.

The allelopathic chemicals present in cornmeal release natural substances that impede the development and germination of weed seeds, significantly reducing the weed population in your garden. It acts as a pre-emergent herbicide, eliminating weeds before they even have a chance to sprout.

Benefits of Using Cornmeal for Weed Control

Using cornmeal as an organic weed control method offers numerous advantages. Let's explore some of the key benefits:

  1. Organic and Non-Toxic: Cornmeal is a natural product that does not contain any harmful chemicals or toxins, making it safe for your plants, pets, and the environment. This makes it an ideal choice for those practicing organic gardening techniques.
  2. Slow-Release Fertilizer: Apart from its weed control properties, cornmeal also acts as a slow-release fertilizer, providing essential nutrients to your plants over time. This helps in promoting healthy growth and vigor.
  3. Cost-Effective: Cornmeal is readily available and relatively affordable compared to other synthetic herbicides. It provides an economical solution for weed control while being environmentally friendly.
  4. Long-Lasting Effect: The effects of cornmeal on weed control can last for several months, minimizing the need for frequent applications. This saves you time and effort in managing weed growth in your garden.

Application of Cornmeal Weed Control

Now that we understand the benefits and mechanism behind cornmeal weed control, let's discover how to properly apply it for optimum results:

1. Preparation:

Before applying cornmeal, it's essential to prepare your garden properly. Remove any existing weeds and debris from the area to ensure that the cornmeal comes into direct contact with the soil.

2. Cornmeal Application:

Spread a layer of cornmeal evenly over the soil in your garden beds or around your plants. It's recommended to use approximately 20 pounds of cornmeal per 1,000 square feet of the area. Ensure that the layer of cornmeal is around 1/4 to 1/2 inch thick for effective weed suppression.

3. Watering:

After applying cornmeal, lightly water the area to help activate the weed-controlling properties of the cornmeal. This will aid in the release of the allelopathic chemicals into the soil, further inhibiting weed growth.

4. Reapplication:

In order to maintain weed control, you may need to reapply cornmeal every few months. However, the duration between applications may vary based on your specific garden conditions and the level of weed pressure.


Based on the scientific evidence and the benefits it offers, it is clear that cornmeal is indeed an effective method for organic weed control in your garden. Its non-toxic nature, slow-release fertilizer properties, cost-effectiveness, and long-lasting effects make it an attractive option for individuals seeking natural alternatives in gardening.

Now that you have learned how cornmeal can kill weeds and the proper application techniques, you can confidently incorporate this organic approach into your gardening routine. Embracing sustainable practices not only helps to preserve the environment but also ensures the health and vitality of your plants.

For all your organic gardening needs, visit Friendly Organics Canada, your go-to source for specialty food, health markets, and organic stores. Experience the power of organic gardening with cornmeal weed control and witness the remarkable difference in your garden.