What is the Difference Between Wet and Dry Mulch Coloring Systems?

Posted on: Jun 08, 2016 - 09:00 AM | Recycling Equipment University
Author: Darrin Martin
Colored Mulch
Red-colored mulch - CC Image courtesy of Osseous on Flickr

Colored Mulch

Colored mulch is in high demand by consumers because it adds significantly to the overall look and consistency of landscaping projects, both commercial and residential. Because of this, it is an avenue of potential added income for those in the wood grinding business. According to Dan Brandon, marketing manager for Morbark, Inc, “ By coloring mulch, the retail-selling price can sometimes be two to three times greater than uncolored, raw grind.”


Several companies, such as Amerimulch, T.H. Glennon Co., Inc., Bandit Industries, Concept Products Corporation, and Colorbiotics manufacture coloring system attachments for existing wood grinders.  And some Rotochopper grinder models have a built-in coloring system to allow for simultaneous grinding and coloring of landscape mulch.

Machine with colored mulch


Wet vs. Dry Coloring Systems

There are two main types of coloring systems. Wet (liquid-based) and dry (granular or powder-based). Each has their particular strong points and drawbacks, but both systems work well to achieve a uniform and attractive end product.


Wet Colorant

Liquid-based colorant is the most widely-used method of applying color to mulch because it is easily adaptable to many different grinder types. Liquid-based colorant is a two-step process, with the wood being ground first and then the color applied after.


Wet colorant typically uses more water than dry colorant and the mulch colored by a wet coloring system requires more drying time for the color to set. However, some operators feel that a powder colorant is more difficult to dispense in a grinder.

Liquid colorant in a wood grinder

Dry Colorant

Dry coloring systems, such as the Color Critter by Bandit, are attached to the wood recycling equipment. In this case, the system uses granular pigments which are applied to the wood through the infeed conveyor during the final grind of material with a garden hose used to wet and disperse the dye into the wood. This process uses less water than a liquid-based system so the finished material does not need as long to dry after color application. In addition to the time factor, a drier (lower weight) product decreases freight costs.


Powdered mulch colorant Powder colorant - Image courtesy of Faltech Industries


No matter which coloring system is used, the colored mulch market continues to be strong. Demand is high and prices of colorants have decreased even as improvements are made to colorants, such as added mold and fungus protection. An experienced heavy equipment specialist can help determine the best way to add mulch colorizing to any wood grinding operation.

To learn more about the wood waste recycling industry and ways to address future “green” market trends contact one of our equipment specialists at Apollo Equipment.net. You can visit us online www.ApolloEquipment.net or call 800-982-2844.