The three most common colors are black, brown and red. Some people like mulch to blend in with their plants while others prefer a contrasting look. It’s up to you to decide your proclivity. But in general use brown mulch for red brick homes, black mulch for grey homes and red mulch for warm toned houses. Bear in mind that red dyed mulch is the most expensive color, black mulch is the second most expensive, and brown mulch is usually the cheapest color to purchase.