The trend of using dyed mulch in landscape beds emerged early in the 21st century. Dyed brown, red and black mulches became the most commonly used colors in shrub and flower beds.
More and more homeowners began requesting dyed mulches. Why? Because those mulches hold their color longer and don't fade or “bleach out” as fast as natural wood mulch products.
Regular shredded mulch is less expensive (30% to 40% cheaper) but fades to a gray color after just one or two months in the sun. Dyed mulches hold their color through the summer, and often into the next year, with minimal color loss. This provides better long term value.
The colorant used in the photo above is formulated to be non-toxic to animals and plants. Check with your mulch supplier for complete details on the product label when ordering dyed mulches.
These colorants tend to "set" once the mulch has been spread and given some time to dry. Up until that point, colorants can rub-off on hands, clothes and pavement. Colorant washes off 'chipped' hardwood mulches much more easily than shredded mulches.
Insects will favor a moist environment that's close to your house whether the mulch is wood, stone, or otherwise. Some recommendations call for perimeter insecticide applications around the foundation of your home to ward off destructive insects like carpenter ants.
Other recommendations call for no mulch (of any type) close to the foundation of a house, for a distance of several feet. Most professional pest applicators recommend using baits for ant problems, always read and follow label directions.
As with other wood-based mulches, you should fertilize the plants in your shrub bed with a nitrogen fertilizer before applying wood-based mulch. This will counteract nitrogen depletion in the soil which occurs when wood mulches breaks down.