Black Mulch Dangers

Black mulch has been dyed black and is used to add aesthetically pleasing colors and textures to gardens and flower beds. Although there are benefits of using this product, there are also dangers. It is important to be aware of such dangers before deciding if black mulch is right for your garden.

Features

Black mulch provides health to plants while providing a garden or flower bed with a non-traditional appearance---and is designed to allow the bright colors of plants and flowers to become more noticeable against a dark background. Plants that would otherwise fade into the scenery will stick out when black mulch is used. However, this type of mulch can create problems.

Properties

Black mulch is made up of wood chips or strips. In some cases, mulch is made from CCA pressurized wood---which can cause serious harm to plants and the ground. Mulch that has been formed from raw wood is much better for plants and the environment. The wood pieces are then dyed using iron oxide or vegetable dyes. Some companies may use dyes that are not safe for plants, so it is important to check all labels.

Leeching Problems

One of the biggest problems that black mulch produces is that sometimes the dyes or chemicals in the wood leech into the ground surrounding the plants and flower beds. According to several studies conducted by Solo-Gabirele and Townsend, Tolaymat and Blassino, in 1999, 2000 and 2002 respectively, recycled mulches were often made from CCA treated wood which stands for Chromated Copper Arsenate. This kind of wood contains arsenic. When the mulch is spread, the CCA leeches into the ground.

Environmental Problems

The chemicals in CCA-treated woods are very harmful to the environment. However, that is not the only danger. The dyes in the mulch are chemically based. The chemicals in the dyes can cause damage to plants and the earth itself. Extreme weather such as rainstorms and extreme heat can cause the dyes to react and release chemicals into the ground.

Additional Problems

Another problem with black mulch is the issue of staining. Some dyes will come off during rain or snow, which will cause the dye to move from the mulch and into the ground. The mulch will appear ugly and dried out. Another problem that black mulch has is the issue of fading. During constant sun exposure, the black mulch will gradually fade to an ugly gray.

References

• University of Florida: CCA Mulch Studies
• Do it Yourself: Colored Mulch
• Garden Web:colored mulch problems