Annual Garden Mulch
Partially decayed compost is an excellent mulch for annual garden beds. Compost gives nutrients to the plants, as well as building soil structure. Compost can be made of many different organic materials, such as plant matter, grass clippings, straw and food scraps.
Perennial Garden Mulch
Perennial gardens respond well to compost, since it delivers essential nutrients, establishes strong soil structure, and helps regulate temperature. Compost also significantly reduces problems with garden pests, according to the Recycle Works program website. Perennial gardens may also benefit from a mulch made of pine needles. Pine needle mulch has the same advantages as compost mulch, and is ideally suited for perennial gardens since pine needles last for 2 to 3 years before decomposing.
Vegetable Garden Mulch
Vegetable gardens often benefit from partially decomposed compost. Compost provides important nutrients for all types of vegetables, but since some vegetables prefer warm environments and others prefer cooler ones, the compost may need to be supplemented with other mulch materials. Black plastic is an excellent mulching material for vegetables that prefer heat, such as tomatoes and eggplant. Small punctures in the bottom of the plastic will allow drainage while raising soil temperature. Vegetables such as lettuce and peas, which prefer a cooler soil temperature, will not not thrive with black plastic mulching material.
Permanent Landscape Mulching
The best mulch for trees, bushes or plants that are part of a permanent landscape is one that stays in place for a long period of time. According to the University of Virginia Cooperative Extension, wood chips or wood bark will stay in place for years, but should still be replenished each year since they are organic material. Wood chips or wood bark may absorb a lot of soil nitrogen, so these mulches may need to be supplemented with a fertilizer containing high nitrogen levels.