Shopper's Guide to Bark Mulch (cont)
By: Charlie Nardozzi
Cost of Bark and Wood Mulch
Of course prices vary across the country, depending largely upon your distance from the source, the specific type of mulch, and local promotions. In general, expect to pay anywhere from $1 to $3 per 2-cubic-foot bag, or $3 to $6 per 3-cubic-foot bag. Buying in bulk saves money, but you'll need to have your own truck. One pickup-truck load (about 1-cubic-yard) costs $14 to $25.
How to Mulch
Two good rules of thumb are to mulch with 3 to 4 inches of bark mulch each season and to avoid mulch layer buildup (and potential nutrient deficiency problems) by removing old layers of undecomposed mulch before adding new layers. Coarse-textured mulches, such as shredded bark, can be applied thicker than fine-textured mulches, such as cocoa hulls. However, there are variations and exceptions related to the type of plants you're mulching and your landscape situation.
Mulching Your Plants
Whatever the type of plant, it's rarely advised to mulch more deeply than 6 inches. Mulch layers thicker than that might reduce air circulation in the soil, which will retard plant growth. Also, don't pile mulch around the main stem of a plant where it enters the soil. The added moisture and insect haven that results could damage the plant you're trying to help. Spread the mulch so that it covers the "dripline" of your plant.
Annuals and Perennials
To avoid encouraging stem rot diseases, use a 2- to 3-inch layer of mulch around soft-stemmed annuals and perennials.
Trees, Shrubs, and Vines
Even around older plants with thick bark, don't crowd mulch around their bases. Most won't succumb to stem rot as quickly as soft-stemmed perennials, but it can happen just the same.
Vegetable gardeners usually prefer to use mulches that decompose more rapidly than wood and bark and add nutrients to the soil in the process. A common example is a thin layer of grass clippings. Because vegetables grow fast and prefer optimum soil conditions, a bark mulch that is tilled into the soil before it is decomposed might steal nitrogen from roots and so is best avoided. However, a bark mulch can give well-tended vegetable gardens a much more refined look.
Which mulch you choose depends on the site:
Areas Prone to Flooding: Nuggets last many years without breaking down, but they're not useful in wet areas or on steep slopes because they float and wash away easily. Similarly, don't use a fine particle mulch, such as cocoa hulls, in windy or seasonally flooded areas since they can blow or float away easily. Of course, aesthetics may weigh heavier in your final decision. Although cocoa hulls float, you may be willing to reapply them because you like their dark, rich color and chocolaty smell.
Slopes: On steep slopes, shredded mulch is best, and hardwood holds better than softwood. However, hardwood mulch tends to break down faster than softwood and may need to be reapplied sooner.
Pathways: For easiest walking, use shredded bark or pathway bark mulch. The irregularity of shredded bark and the small particle size of pathway bark are better for walking compared with mulches with larger particle sizes.
Amount of Mulch to Cover 100-Square-Foot Area
Mulch Depth (inches)/ Amount of Mulch Needed
4 inches/ 34 cubic ft.
3 inches/ 25 cubic ft.
2 inches/ 17 cubic ft.
1 cubic yard = 27 cubic feet = one small pickup load of bulk mulch. Bark mulch bags are commonly sold at garden centers in 2- or 3-cubic-foot units.