A List of Mulch

Wood Mulch

• Wood chips and bark nugget mulches are usually used in ornamental beds because they provide an attractive ground cover. The wood breaks down slowly, but it still requires annual replacement to look its best. The wood suppresses weed growth and helps retain soil moisture well. Sawdust is also sometimes used as a mulch, although it can compact and make it hard for water to penetrate the soil beneath.

Straw Mulch

• Straw mulching materials are usually used in vegetable beds because they aren't as ornamental as wood. Seed-free grain straw or pine straw are typically used, with pine straw providing a more ornamental option. Straw can blow out of the bed when first applied, but it doesn't compact on top the soil. The straw prevents weeds and conserves moisture while also insulating the soil against temperature fluctuations. Cornstalks are sometimes used instead of straw to mulch vegetable gardens.

Leaves and Leaf Mold

• Dry, fallen leaves provide a mulching material, but they may compact and reduce water penetration to the soil beneath. Chopping up the leaves before application can minimize this issue. Leaf mold, made from composted leaves, is sometimes used as an attractive mulching option that doesn't compact. The leaves provide nutrients to the soil as they break down. They also conserve soil moisture, but weeds can easily grow through the mulch layer.

Compost

• Compost improves the soil by adding plant nutrients. It also works exceptionally well at retaining moisture. Compost is usually made from a yard, garden and kitchen waste. You can also compost grass clippings for a high-nitrogen variety of compost. Although it conserves moisture, weeds can grow in the compost layer. The compost may also introduce weed seeds to a bed if the plant materials in the compost haven't decomposed completely.

Plastic and Fabric

• Black plastic mulch prevents nearly all weed growth and prevents moisture loss through evaporation. The plastic can also help warm the soil earlier in spring. Fabric provides the same benefits but supplies a more permanent option for perennial beds. Water doesn't penetrate plastic so you must use drip irrigation beneath the mulch layer, but moisture can still soak through a fabric mulch. Both plastic and fabric are unattractive, but you can cover them with a more attractive wood mulch if desired.

Stone Mulch

• Gravel, pebbles and stones reduce weeds, but they are only suitable for permanent mulched areas. Most stone mulches contain limestone, which leeches into the soil and cause it to become too alkaline for some plants. The stones also work their way into the soil, so the mulch becomes impossible to remove, although placing landscape fabric beneath the stones can minimize this problem. Stone mulches are most suitable for paths or rock gardens.