It’s a frequently asked question. By now most folks know they should apply much in Texas, but we frequently hear “What is the best mulch to use?” often times followed by “What about that rubber mulch?”. Are there benefits to rubber mulch? Sure! It’s a recycled product that keeps millions of unwanted tires out of our nation’s landfills. It also works to reduce evaporation (water lost from the soil) around plants & landscapes AND can even reduce soil erosion. But the benefits tend to stop there. In reality, there are quite a few concerns when it comes to rubber mulch products when compared to organic products (that were once trees) like cedar, hardwood or even cypress mulches.
Top 10 Reasons:
You Might Think Twice Before Using Rubber Mulch Products
1) It’s less effective establishing new plants (Calkins et al. 1996)
2) Less effective controlling weeds (Bush et al. 2001, 2003)
3) Reduced tree growth, and increased tree mortality (Stokes 2012) 4) Can lead to Zinc toxicity (Bush et al. 2001, 2003)
5) More likely to ignite (highly flammable) (Steward et al. 2003)
6) Attracts Cockroaches (vs wood mulches) (Snoddy and Appel 2013)
7) Decomposition of rubber means that it breaks down into unwanted products, including heavy metals and other hazardous chemicals of concern. These can leach into the surrounding soil and water. -Polycyclic aromatic hydrocarbons (PAH) such as naphthalene, phthalates, butylated hydroxytoluene, etc (Llompert et al. 2012)
8) Lacks the water holding capacity of organic mulches (DeForest et.al. 2009)
9) Those unnatural colors, reminiscent of fake plants! Ugh!
10) And Most importantly you don’t get the benefit that organic mulches have as a host to beneficial microoraganisms which help cycle nutrients and increase water uptake! (DeForest et.al. 2009)