Sunday, December 31, 2006
Organic mulch was at one point alive. Inorganic mulch never was. While it may be surprising to many gardeners, inorganic matter can be used effectively as mulch and depending on what type of material is used, encourage your garden to grow and flourish. Inorganic mulch selections have grown to include a variety of products that are much more interesting than the gravel or black plastic of days gone by. Before making your next mulch purchase, explore the world of inorganic mulch and see if it is the right finishing touch to your garden.
Mulch is recommended by most gardening experts for moisture retention. The NC State University horticulture department estimates that ten to twenty-five percent of soil moisture is lost through evaporation. When it does rain, the raindrops cause the soil to compact increasing water runoff and soil erosion. A two to four inch layer of mulch can retain moisture in the ground and increase soil aeration. Not only will the mulch reduce the gardener's need to water plants, as is noted by the U.S. Department of Agriculture, Natural Resources Conservation Service, mulch will also maintain an even soil temperature, prevent weed growth and keep the garden environment clean. Mulch gives the garden a finished look, thus increasing its visual appeal.
Certain gardening conditions do contraindicate mulch applications. If your garden beds are severely infected with slugs , snails or other insects, mulch application may increase your problems. It may be prudent to not mulch for a year, as you manage your pest problem. Poor drainage may also be a reason for not mulching. At the very least research the best type of ground cover for areas that do not drain well. Mulch maintains moisture in the ground. If you have an area that does not drain well, you could be creating swamp like conditions if you mulch with moisture retaining material. Bacteria and fungus can grow and damage plants planted in too moist ground. Furthermore, this area will prove a perfect breeding ground for mosquitoes. Before mulching poor drainage areas, either solve the drainage problems or research ground covering that promotes good drainage.
Inorganic mulch is generally reserved for those areas of your landscape that are permanent in nature. The area around foundation plantings, walkways and areas that are not planted with annuals are perfect areas to consider using inorganic mulch. Gravel is one type of inorganic mulch that allows your plants to grow yet inhibits weed growth. Gravel sinks into the ground and is difficult to remove if you decide to change your landscaping. It is best to only use gravel in areas where your plantings are permanent.
Gravel can be purchased from mulch suppliers, many of whom can be found on line. Bulk gravel , the white gravel often seen under trees or at commercial buildings, is available by the truckload or can be purchased by the bag at your local home improvement store. If a large quantity of either white or grey gravel is desired, it may be wise to also contact your local stone dealer for pricing.
Decorative gravel is a term used to encompass different types of inorganic mulch. Granite is one type of inorganic mulch that comes in a variety of different colors. Granite is crushed to create different colors of landscape coverings such as ruby red granite, orange granite, black and pewter granite. Stone companies, many of which have an on line presence, have a wide selection of granite based groundcovers. Granite dealers may also sell quartzite, made from rock rich in quartz such as limestone and granite. Quartzite comes in vivid colors such as carmel and wintergreen. Over twenty different colors of granite based landscape mulch are available.
Pebbles, brick chips and lava rocks are also used as inorganic mulch. Brick chips are very attractive as ground cover when used with brick paving stones to create garden pathways. Lava rocks come in a variety of sizes and can be found in red and black and golden colors. Pebbles come in a variety of colors and sizes and can be purchased in bulk or in bags to decorate smaller areas.
Black landscaping material is also considered an inorganic mulch. Normally landscaping material is not used by itself but rather as a base for organic mulch or landscaping stone. Landscape fabric is not attractive by itself and it normally needs to be weighted down by stones or fastened to the ground where it is used. Landscape material is porous, thus allowing water and nutrients to seep into the soil. Its' main purpose is to prevent weed growth. Landscape material is easier than gravel to move if you decide to change your landscape design. It can be poked through or cut to allow new plantings. A word of warning, the more you mess with your landscape material the less effective at weed control it becomes. A small hole cut for planting a new hosta can suddenly become a huge rip in your landscape material, especially if you have pets or other wildlife in your garden. It is best to use landscape material on finished gardens or under foundation plantings.
Black plastic was used for a long time as landscape fabric. Plastic is not permeable so water nor nutrients reach the ground where plastic is used. Most garden resources no longer recommended the use of black plastic in landscaping.
The most exciting news in inorganic mulch are the recycled rubber alternatives that are relatively new to the market and are becoming increasing available. Rubber mulch allows drainage, retains moisture and provides insulation for you garden. Permalife Landscape Mulch sells its rubber mulch with its' polyurethane/ acrylic coating in six different colors ranging from a natural looking "Boston Brown' to a tropical feeling blue. This mulch does not promote or sustain fungus, is non toxic and does not stain. In fact Permalife offers a five year replacement warranty on the mulch it sells. Other companies also sell similar products and one, RubberStuff Landscape Mulch ,can be found at select Home Depot stores. Many mulch companies do sell recycled rubber mulch but it is a special order product. Most companies selling recycled rubber mulch will provide samples on request.
Inorganic mulch is perfect under foundation plantings or in areas where you do not anticipate changing your landscaping. While these products do not improve the soil, they do provide all of the other benefits of mulching. Most inorganic mulches will allow liquid fertilizers to seep into the ground thus keeping your plants healthy. While utilizing inorganic mulches seems to go against the earthy nature of most gardeners, there are times when it should be considered and utilized. It does not need to be replaced as frequently as organic mulch and for the gardener who is short on time it may be the solution to keeping a garden well tended and attractive. Inorganic mulch is not for everyone, but with new products coming out everyday, it may soon be found in more gardens then it used to be.