There are numerous reasons why we don’t recommend to use dyed mulches in the landscape. Aside from looking artificial here are a few more:
Origin of Dyed Mulch
Dyed mulches (black, red, green and other colors) are usually (with few exceptions) made up of recycled wood waste. This trash wood can come from old hardwood pallets, old decking, demolished buildings or worse yet pressure treated CCA lumber. CCA stands for Chromium, Copper and Arsenic; chemicals used to preserve wood. This ground up trash wood is then sprayed with a tinted to cover up inconsistencies in the wood and give it a uniform color.
Effect of Dyed Mulch
This dyed wood mulch does not break down to enrich the soil as good mulch should. Instead it leaches the dye along with the possible contaminants (chromium, copper, arsenic and others) into the soil harming or even killing beneficial soil bacteria, insects, earthworms and sometimes the plants themselves. These wood mulches actually rob the soil of nitrogen by out-competing the plants for the nitrogen they need for their own growth. In addition, they can be hydrophobic and actually prevent water from getting down into the soil and the roots of your plants.
What We Use
We sell only 100% natural bark muches that are natural in color without additives. Shredded bark mulch breaks down over the course of a season or two without the harmful effects of dyed mulches.