The Pros and Cons of Rubber Mulch

Rubber Mulch

Over 290 million tires are discarded in landfills each year, but some innovative companies are developing creative new ways to reuse rubber as mulch. Rubber mulch provides a low-maintenance and long-lasting cover for playgrounds, gardens, and landscapes. It has some drawbacks, however. Here, we explore both the pros and cons of rubber mulch to help you decide whether it’s right for your space.

What is rubber mulch?

Rubber mulch is made of recycled rubber, usually from tire waste. Like all mulch, it is used in gardens and landscaping to suppress weeds, retain moisture, and keep soil cool in the summer and warm in the winter. It’s also used in playgrounds to provide a safe, cushioned surface for kids.

You can purchase rubber mulch in nugget or shredded form, in pre-rolled sheets, or in rings for wrapping around trees and shrubs. Some planning is recommended before installing it, especially when it comes to long-term plant placement. It’s difficult to move once it’s already been applied, and you’d hate to cut holes for your plants just to change your mind about the placement and ruin an entire sheet of mulch.

Advantages of rubber mulch

It is available in an array of colors to help maintain the aesthetic of your garden beds and landscaping. Rubber mulch comes in black, blue, red, and green to accent your landscape and imitate the look of organic wood.

It provides a safe, cushioned surface for kids on playgrounds and in play areas. Six-inch-thick sheets of rubber mulch relieve pressure on the joints from the pounding of athletics while also providing a cushion to prevent injury in case of falls.

Rubber mulch lasts much longer than regular mulch. Rubber degrades very slowly, which means it’s going to be around for a while. Most manufacturers claim their products last up to 10 years.

It is less likely to be scattered by wind or washed away by the rain because it is heavier than organic mulch. Leaf blowers and pressure washers are less likely to displace it.

It requires less maintenance once it has been installed properly. You’ll have little to no upkeep, such as annual re-mulching. In contrast. organic mulch fades and decomposes. 

It won’t attract pests because rubber mulch is not organic. Termites and carpenter ants don’t care for it..

It inhibits weeds because the mulch holds and dehydrates weed seeds before they can germinate. Rubber mulch also blocks sunlight and compresses the surface of the soil, similar to regular mulch, providing a dull environment for the weed.

Rubber mulch is a good insulator, providing warmth to the top layer of soil. This helps flowers bloom earlier so they continue to flower later into the growing season.

Disadvantages of rubber mulch

A pungent smell can emanate from rubber mulch in extreme heat. Have you ever been in a tire shop on a hot summer day? That’s the smell. This is due to the emission of gas from the rubber.

It’s more expensive than organic mulch initially. The cost of rubber mulch can be three times higher, or more, than organic mulch. Additionally, you’ll need to lay substrate, such as a geotextile landscape fabric, to separate the mulch from the soil. However, because it degrades very slowly, rubber mulch may be more cost effective in the long run. 

It’s not biodegradable, and it lacks key nutrients needed to replenish the soil.

Rubber mulch may contaminate soil. Rubber leaches zinc, aluminum, cadmium, and chromium, although there hasn’t been enough study about the specific effects of rubber mulch on gardens to say just how harmful this leaching process is. 

There are potential health risks include exposure to volatile organic compounds (VOCs) that have been linked to cancer and neurological conditions. When used as padding for children’s playgrounds, rubber mulch can crumble under small feet, and those crumbles can make their way into children’s mouths.

Upkeep is slightly complicated with rubber mulch, as weeds and natural debris that accumulate must be pulled and discarded by hand. Tilling is not an option because rubber mulch cannot be mixed in with the soil like organic mulch can. 

Rubber mulch is highly flammable, burning faster and stronger than regular mulch and releasing a toxic gas. Be sure not to lay rubber mulch near fire pits or barbecue grills. It is also not recommended in smoking sections. A high carbon-to-nitrogen ratio makes it harder to extinguish.

It harbors some insects, like Asian cockroaches. The National Library of Medicine suspects that the rubber mulch provides a humid home for these insects.

It’s susceptible to some fungi that attach to the mulch’s chemical additives.

Landscape fabric can become clogged with tiny particles of soil, which prevents water from filtering through. This will suffocate insects, important to the ecosystem, like earthworms.

Rubber mulch vs regular mulch

There are both advantages and disadvantages to inorganic and organic mulch, as outlined in this Lawn Love article. As a consumer, your job is to choose the option that serves you best.

Yes, rubber mulch provides safety for play areas and is a low-maintenance addition to your gardens, but is it worth the risk of potential contamination of your soil and the surrounding plants that you’ve put so much love into? It also poses a fire hazard and is not recommended for homes with smokers, or in areas prone to wildfires.

Organic mulch is less expensive and also has minimal impact on the environment. However, it is a magnet for pests like termites and carpenter ants. It also absorbs nitrogen from the soil, which is undesirable in vegetable gardens and most plant beds. 

 Rubber MulchRegular Mulch
CostAbout $11 per cubic footAbout $3 per cubic foot
Durability10 years or soNeeds replenishing every year or two
PestsAsian cockroachesTermites, carpenter ants, mice, and more
Plant HealthMay cause contamination to the soilRobs soil of nitrogen that certain plants need
Fire HazardExtremeModerate
Health risksCan leach heavy metalsNo
MaintenanceLowHigh

FAQ:

Q. How do I install rubber mulch?

First, clear the area of all grass, wood chips, rocks, stumps, and other debris. It must be graded for proper drainage. Experts recommend using a commercial grade geotextile landscape fabric to help filtrate, drain, separate soil layers, reinforce, and stabilize.

* Overlap the seam of the fabric a minimum of three inches, and fasten it properly. 
* Properly secure the fabric around the perimeter and around all installed equipment.
* If installing above ground, use a retaining system.
* Finally, lay your mulch

Q. Does rubber mulch emit odor?

Yes, the smell of rubber can be strong in extreme heat. 

Q. Does rubber mulch release toxins?

Rubber mulch is suspected of being toxic to plants, containing high levels of zinc which leaches into the soil, causing chlorosis. It also poses health concerns, as it releases heavy metals, plasticizers, and accelerators into the environment.

When selecting the ideal mulch for your space, there are many factors to consider. Are mulch costs the most important element? What about its appearance? Is the risk of potential soil contamination a deal breaker? At the end of the day, you’ll have to weigh out the pros and cons to make your most informed decision.

And as always, Lawn Love lawn care professionals are here to help you figure out the rest.

Photo Credit: PxHere

Madeline Hoppe

Born and raised in Tampa, FL, Madeline Hoppe is a customer service expert with a deep respect for the written word. In her down time, she enjoys low-key nights watching movies with her family or heading to one of Tampa Bay's local beaches on a summery day.