Colored mulch can have a lovely aesthetic affect on your garden if you use it right. However, that affect can diminish over time when the color of the mulch begins to fade to a dull grayish shade. Luckily, you don't have to replace the mulch. You can simply dye it back to its original color, using a mulch colorant, such as BarkBrite. You can also use the colorant to dye mulch that has never been colored before.
Determine the color of dye you would like. You can make your mulch practically any color of the rainbow, but it's best to choose one that will not clash with the plants in your garden. Good bets are black, brown and red. Purchase colorant at your local garden center or home-improvement store.
Pour 6 qt. of lukewarm water into your garden sprayer. Check the cap on the bottle of mulch colorant to ensure that it is on tight. Shake the bottle vigorously up and down for at least 15 seconds to mix the dye.
Pour the colorant into the garden sprayer. Put the top on the sprayer and shake it for at least 15 seconds, or leave it open and stir vigorously with a plastic or metal mixing spoon.
Cap the sprayer, if needed, and take it to your garden, holding the sprayer upright. Pump the sprayer 15 times. Tilt it downward at a 45-degree angle or extend the hose. Either way, keep the nozzle about 5 inches away from the mulch you'd like to dye.
Spray the dye onto the mulch in rows from left to right, starting at the far left corner. This will help to ensure an even coat. Let the mulch dry overnight before resuming gardening activities.