The best type of mulch is one that fits your needs. If you have an area where you want to grow vegetables, then using a mulch that contains compost will help retain moisture while providing essential nutrients to the soil and plants. Shredded bark is also a great type of mulch because it can be used on slopes and areas with poor drainage. The disadvantage of using bark is that it's lightweight, so don't use it if your area floods or has a lot of rain.