Endurant EMCBLACK5GAL Mulch Colorant Black 5 Gallon. Endurant Mulch Colorant is a liquid pigment, available in four blendable colors, which instantly and inexpensively enhances a landscape's appearance, refreshing existing faded installations with an unlimited range of shades. Endurant Black is a popular shade for its high contrast added to landscapes. An additional benefit of on-site coloring is the elimination of the significant costs associated with purchasing colored mulches, which means this product will immediately begin paying for itself.