Mulch is a popular material used in gardening. It is any material used to prevent weed growth and retain soil moisture. It is also used to give landscapes a certain aesthetic appearance depending on the color of the mulch if it is dyed. One of the most popular mulch colors is black.


There are several varieties of black mulch, including shredded hardwood, rubber and plastic. All are effective in retaining water, keeping soil warm and controlling pesky weeds. However, many consumers prefer natural hardwood mulch because of its aesthetic appeal. Common hardwoods used include beech, ash and poplar.

Dyeing Ingredients

The most common ingredient for turning mulch black is coal. Water-based paints and natural vegetable dyes are also commonly used. Black mulch dyes can also include chemical binders and preservatives that assist in the coloring process. There are also dyes made from the materials created by incomplete petroleum combustion. This specific type should be avoided because the dyes are carcinogenic and can be harmful to both the plants and the soil itself.

How Mulch Is Dyed

Manufacturers create black mulch by loading regular shredded mulch into a hopper placed on a huge trailer. The liquid coloring material is then mixed with water in a machine and sprayed on the mulch as it passes through the machine. The colored mulch is then transferred to a stockpile using a conveyor belt. Gardeners can also create black mulch by creating compost piles in their backyard using their choice of ingredients.

Dyed Mulch vs. Regular Mulch

Although regular mulch costs less than dyed mulch, it tends to fade into a gray color after just a few months. Dyed mulches retain their color throughout an entire year and even into the next. Because it lasts longer, colored mulch does not need to be replaced as often. As a result, many consumers prefer dyed mulch to regular mulch.


Black mulch is a popular choice among many gardeners and landscapers not only for its style but also for its function. For example, black absorbs and retains sunlight more so than other colors, thereby warming the garden soil and enhancing plant growth.


Always check the label before buying black mulch made of any material. Some manufacturers use chromate copper arsenate, a toxic element to garden plants and other living things, to treat their wood. Some black mulches made of plastic also contain zinc, benzene and other potentially harmful substances. To be safe, it is best to purchase raw wood pieces that have been treated naturally.