Mulch Glue Explained: What It Is and How It Works

Tired of your mulch washing away every time it rains? Then mulch glue might just be your new best friend. A spray-on product that binds mulch together, mulch glue keeps your mulch where you put it, not running down hillsides or onto your driveway.

I use mulch glue to keep mulch off of my pool deck, where it would end up after every rainstorm. It’s easy to apply, and you can find it at most home centers, or you can make your own at home with a few simple ingredients.

Ahead, learn all about mulch glue, including what it’s made of and how best to apply it around your yard, with help from two industry experts— Brion Amstutz from Nationwide Protective Coatings and Andy Slamans from Petramax.

What Is Mulch Glue?

“Mulch glue, in its essence, is a landscaping glue that holds mulch, wood chips, pine straw, and even sand or pea stone in place,” Slamans says. It dries clear, bonds the top layer of substrate together and helps it stay in place against wind, rain and foot traffic.

What Is Mulch Glue For?

Mulch glue is an effective way to keep loose landscape materials like mulch or pea stone in place—whether in garden beds, on slopes or anywhere they tend to wander.

When the glue dries, it binds the mulch into a mat-like layer that is more resistant to movement. Around my pool, mulch constantly ended up on the pool deck, but we didn’t want to switch to stone or gravel, so we tried mulch glue instead. Now, after rainstorms or get-togethers, the mulch stays off the pool deck and inside the garden bed where it belongs.

What Is Mulch Glue Made Of?

Ingredients will vary among commercial products, but most use a base of urethane or acrylic binders. A few products also offer “cross-linked” products that use both urethane and acrylic binders for added durability and performance.

“There are different resins that are used to formulate mulch glue,” says Amstutz. “Here at Nationwide, we have our economical grade Mulch Glue that is made with a Modified Acrylic Resin that has excellent performance. However, we do have a 100 percent Acrylic Resin formulation called Mulch Glue PRO that is crystal clear and has better durability and performance.”

Slamans describes his company’s mulch glue as “a proprietary blend biodegradable polymer, meaning it’s a product that is meant to break down over time.”

How To Use Mulch Glue

Apply mulch glue to dry mulch with a pump sprayer. “We recommend that the weather conditions are dry 24 hours to two days before application so the mulch is dried out,” Slamans says. “And you don’t want rainy weather for at least two days after.”

Most brands require dilution before application, so be sure to follow the manufacturer’s instructions and plan to apply at least two coats. “Every application is different,” Amstutz says. “High volumes of mulch will probably need more than one application” to allow each piece to receive a thorough coating.

How To Make DIY Mulch Glue

You can make a cost-effective mulch glue at home. You’ll need latex-based kids’ school glue, water, a thickening agent like cornstarch, and a pump sprayer to apply. This DIY solution is not as effective as commercial products so is best for light-duty applications.

• Mix the adhesive: Pour one part white school glue to three parts warm water into a clean pump sprayer.
• Thicken the solution: Add one tablespoon of cornstarch to help the mixture better adhere to the mulch.
• Stir thoroughly: Use a mixing stick to blend the ingredients until smooth.

FAQ

Does mulch glue prevent weeds?

No, mulch glue does not directly prevent weeds from sprouting in your garden beds. “The weeds will still grow under the mulch glue and can penetrate the mulch glue film,” Amstutz says.

How long does mulch glue last?

“Twelve months is standard,” Slamans says, “but it will vary based on the weather.” Plan to reapply more often if living in a rainy climate and less often in drier zones. “[Nationwide’s] Mulch Glue could last one to two years, but most consumers re-apply every year or when mulch starts to become loose,” Amstutz says.

Does mulch glue really let water through?

Yes, water and nutrients can still reach the soil through mulch glue. “Mulch glue is applied in a manner so that it does not form a continuous film,” Amstutz says. “Water can penetrate through the areas where the mulch glue has not formed a solid film.”

About the Experts

• Brion Amstutz is Sales Director at Nationwide Protective Coatings in Sarasota, Florida.
• Andy Slamans is the owner and creator of the Petramax Lockscape Sticky Mulch Glue.