How to Control Weeds Naturally with Mulch (2024)

FAQs

How to Control Weeds Naturally with Mulch? ›

Mulch's primary role in weed prevention is blocking the sunlight they need to grow. To make this happen effectively, you need to make sure it's thick enough: we recommend 1.5 to 2 inches. But don't over-mulch or your plants won't get the air they need. Weed first, then mulch.

Plus, when it comes to what to put under mulch to prevent weeds, we recommend a granular pre-emergent product that you apply to the bed of mulch. Pre-emergent will keep further weeds from growing, aiding in maintaining a pristine landscape.

The most efficient way of removing the existing weeds and eliminating further growth when it appears would be with a weed killer. Alternatively, you might like to place several layers of newspaper over the area and then re-mulch.

A homemade vinegar solution can effectively kill younger weeds, but is not a permanent solution for tougher weeds, unless you are diligent about reapplying and soaking the roots.

Spray Before Laying Mulch

When replanting a new flower bed or garden plot, use a total weed control like RM18 or Compare-N-Save Quick Acting Weed & Grass Killer to eliminate unwanted grasses and weeds before applying a fresh layer of mulch.

Perhaps the simplest way to keep weeds out is to apply a layer of quality mulch. Not only does mulch help retain moisture, but the barrier created will serve to keep weeds at bay as well. Most homeowners prefer a double or triple shredded hardwood mulch that has been dyed.

Again, you can use a garden hoe or hand weeder or follow the instructions for using a weed killer. If you're mulching around a tree, you can remove the grass or simply put down a layer of black-and-white newspaper, thoroughly water it down and then cover it with your mulch. Add mulch to a depth of 2 to 4 inches.

However, this isn't necessary because mulch will decompose over time and you can just add a new layer on top of the old one! However, you don't want your mulch layer to exceed 3 inches in thickness. So, you can remove some of the old layer if necessary to keep the mulch at the right amount.

To smother the weeds and retain moisture within the soil, the layer of mulch needs to be at least 3 inches thick but no more than 3 inches or you could do damage to tree trunks and shrubs. Even two inches of mulch can let through enough sunlight allowing weed seeds to germinate.

If using standard mulch (and not Preen Mulch with Extended Control Weed Preventer which includes weed prevention), we recommend applying Preen Garden Weed Preventer after spreading the mulch on your flower and shrub beds for best weed control. Sprinkle Preen on top of the mulch and integrate with a rake.

Does vinegar, salt, and dawn really kill weeds? ›

When looking for a natural alternative to herbicides, a co*cktail of vinegar, salt and liquid dish soap has all of the ingredients needed to quickly kill weeds.

There is another natural way to kill Creeping Charlie, and that is by using a mixture of Dawn dish soap, Epsom salts, and vinegar.

Epsom salts (MgSO4) have historically been used as fertilizer; in theory, you could apply them at such high concentrations that they kill plants, but it would take a lot, and could damage soils long-term. ISN does not recommend using Epsom salts as an herbicide.

While weed control products are going to be your best solution for keeping grass out of mulch or rocks, an additional landscaping step that you can take is to make sure that you also edge your plant beds. Edging is the process of creating delineation between your lawn and your landscape beds.

While a good layer of mulch can smother small, young weeds, don't expect it to magically eliminate well-established weeds. It's better to remove any big weeds and patches of weeds before mulching over them, or they'll pop right through. Or, as noted in the previous tip, some may keep on spreading under your mulch.

Spray all weeds with weed killer 1 to 2 weeks prior to mulching. This allows weeds to completely die, making them much easier to pull.

This is an important step because just as mulch can help improve the health of your soil, it can also help weeds grow stronger if they're not removed. So, make sure you pull up and remove any visible weeds prior to putting down your mulch.

While weed control products are going to be your best solution for keeping grass out of mulch or rocks, an additional landscaping step that you can take is to make sure that you also edge your plant beds. Edging is the process of creating delineation between your lawn and your landscape beds.

Apply a Pre-Emergent:

This is the time to prevent weeds. Apply the pre-emergent before mulching.