How to Keep Weeds Out of Mulch (Steps)

Mulching has many benefits for your garden. But do you know how to keep weeds out of mulch?

First of all, mulch adds organic matter to the soil and improves the soil structure, which in turn helps with both drainage and water retention.

Mulching also prevents weeds from growing in your garden.

Although mulching will suppress some weeds, other stubborn weeds will continue to thrive.

In this article, we’ll talk about how to keep weeds out of mulch so that you can continue enjoying the beauty without spending your free time pulling weeds.

How to Apply Mulch to Your Garden

If you want to grow plants from seed, don’t mulch down immediately. If you plant flowers, vegetables, or fruit seeds and add mulch to them, you’ll prevent them from germinating.

Although you want to eliminate weeds, having too much mulch will lead to an empty garden. Wait for your plants to germinate and grow higher than the height of your mulch. Give your garden a few days to allow straggler seeds to germinate since all seeds have a different timeline.

During the germination process, you’ll notice some weeds growing. You’ll need to get rid of them, but there will be a reduction in future weed populations once you’ve mulch. If you’ve already grown plants, you can mulch as soon as you’ve established plants in the soil.

Having a layer of mulch of 3-4 inches deep will prevent weed growth. However, don’t exceed 4 inches of mulch if your plants are shallow-rooted. Your mulch should be uniformly distributed to ensure that the entire garden surface is covered. Although this seems obvious, most gardeners spread mulch unevenly or carelessly, which gives room for weed growth in areas with shallow cover. Once you mulch properly, you’ll help your garden to grow well in several ways.

Why do Weeds Grow in Mulch?

Removing weeds can be a tedious process. They grow well under the same conditions your garden does: nutrients, water, and sunlight.

Weeds use any opportunity to grow and cannot be removed by hands when they gain roots. When plant-based mulch decomposes, it creates a nutrient-rich environment for weeds to thrive.

Weeds are mostly found in contaminated or old mulch. Wind or birds can also distribute seeds into new beds.

How Can I Prevent Weeds in My Mulch?

Here’re a few tips on how to keep weeds away from your mulch:

  • Apply the right amount of mulch. The main role of mulch is to prevent weed growth by blocking sunlight. For excellent results. You need to use enough mulch of 2-3 inches. However, you shouldn’t over-mulch because your plant won’t get sufficient air.
  • Ensure you weed first before mulching. When preparing the garden, remove all old mulch, eliminate any weeds, and place a fresh mulch layer.
  • Use pre-emergent herbicide to treat the soil before mulching.
  • In some situations, especially around shrubs and trees, use landscape fabric before mulching. This blocks weeds from growing but let’s water and air in.
  • Edge around your mulched bed to prevent any stray seeds from accessing your mulch.

The Best Mulch to Prevent Weeds

For landscaping and flowerbeds, use a shredded or chipped bark mulch that has a fairly coarse texture. This mulch decomposes slowly and won’t be blown away, will block sunlight from reaching the soil.

Inorganic mulch such as gravel or stones is ideal for preventing weed growth. However, this type of mulch has no soil-improving benefits.

How to Prevent Weeds with Landscape Fabric

If you’ve not used mulch yet, weed barrier cloth or landscape fabric is a great way to prevent weed growth without limiting access to water and air.

However, landscape fabric is not very effective since some determined weeds will push through the fabric, and these weeds will be tough to pull out. In some cases, the old hand-pulling method is still an effective way to eliminate weed growth in mulch.

How to Kill Weeds in Mulch with Herbicides

Apart from hand-pulling, mulching is one of the most efficient ways of weed control. However, mulching works well when coupled with pre-emergent herbicides. When used in the right way before weeds sprout, pre-emergent herbicides prevent weeds from growing in mulch. But they won’t affect already sprouted weeds.

To prevent weed growth using pre-emergent weed killers, start by raking mulch off from the garden and remove any existing weeds. Read the manufacturer’s instructions keenly and apply the herbicide. Be keen on the label since some plants cannot withstand some types of pre-emergent weed killers.

After applying the herbicide, replace the mulch evenly and ensure you don’t disturb the treated soil. For extra protection, you add another layer of herbicide over the mulch. A liquid herbicide is the best since it sticks to the mulch and doesn’t drop to the soil.

How to Keep Weeds Out of Mulch (Step by Step Guide)


Using mulch is one of the most effective ways of weed control. Additionally, mulching will pay off in several ways over time and will maintain your lush lawn.

The ultimate secret to having the most attractive landscaping beds is knowing how to keep weeds out of mulch.