The decision to use mulch or rock depends on a dew factors including plant material used, budget, maintenance, and personal tastes. We have great resources for both mulch and aggregate rocks. For example, pine bark is one of the longest lasting types of mulch, but it doesn’t offer plants many nutrients when they break down. Soil pH may be reduced by pine bark and pine straw, which would be excellent for acid-loving plants like azaleas, but not for plants that require high-pH soil. Here’s an overview of the most popular mulches:
- Pine bark is a byproduct of the forest industry. It comes in ground and nugget forms, and has a rich brown color.
- Pine straw (pine needles) comes from pine plantations, which produce paper and wood products, and is sold in bales. Unlike some mulches, pine needles are not likely to wash away, because they knit together.
- Mixed hardwood mulch is produced from scrap lumber, recycled pallets, or tree stems that are too small to be used for paper or wood production.
- Cypress mulch is often made from the waste wood generated in the manufacture of these products, but it may also be produced from whole trees cut from wetlands
- Rubber or “playground” mulch is mulch made from recycled tires or other types of rubber. Generally sold in a variety of colors; also available uncolored in its natural color. Favored by low maintenance gardeners looking for exceptional weed control and long color life, rubber mulch can save time and money over conventional mulches as it lasts for well over a decade. Playground rubber mulch offers an extremely resilient safety surface that holds up well in high traffic playgrounds due to the durable colors, the fact that it will not float, and the shock attenuation properties of rubber.
- Gravel, rocks, and pebbles last a really long time and add a more elegant style to any landscape design, but can be higher maintenance since they need to be cleared of all debris in order to look their best. Aggregates also won’t contribute to the soil’s nutrient and organic content or water-holding capacity.