We’ve all heard of the importance of amending the soil properly for gardening and landscaping, but the number of soil amendments sold in garden centers often confuses gardeners. Which is which, and which will work best for your soil conditioning needs?
Types of Soil Amendments
Soil amendments fall into two basic categories, inorganic and organic. Inorganic amendments come from non-living materials such as sand, perlite, vermiculite and crushed stone. With the exception of limestone and gypsum, which are used to increase soil calcium, these are not commonly used in the garden.
However, organic amendments are the opposite. They come from previously living materials such as peat, manures and composts. When leaves, bark, peat, animals and animal wastes are mixed together to decompose, compost or “humus” is the final product. Very commonly used, these materials enrich the soil by increasing the air spaces, adding extra nutrients to the soil, improving the absorption of those nutrients and increasing overall soil fertility.
Why You Need Soil Amendments
Excellent soil is not common around most homes. Even if it was initially, house construction and roadwork often removes the good soil and construction equipment compacts the remaining soil. Furthermore, heavy use of the remaining turf – children and pets playing, for example – continues to compact the soil. Chemical treatments, runoff from gutters and downspouts, removal of existing plants, changes in local wildlife – all of these factors can wreak havoc on soil.
Adding organics loosens compacted soil and results in better gardens. Incorporate organics into the beds throughout the year by working evergreen needles, leaves and lawn clippings into the soil. Amendments such as peat or lime can improve a pH problem, if one exists. Calcium and magnesium deficiencies can be corrected using organic materials such as bone meal or wood ashes, or inorganic materials such as limestone, gypsum or soft rock phosphate.
Mulching is another simple way to add biodegradable materials to the soil. Simply place mulch around the plant, leaving several inches bare closest to the stem to discourage insect invasions and rot. In addition to slowly providing nutrients as it decomposes, mulching is attractive, reduces weeds and erosion, maintains soil temperature and prevents “crusting” that occurs when soil becomes too dry.
Another advantage of adding organics is the attraction of worms. They further assist in the decomposition, increase aeration and leave worm castings, a valuable organic material, behind. A healthy garden is home to many worms, and it all starts with adding organic soil amendments.
Whether you opt for organic or inorganic soil amendments, if you use them properly, you soil will improve and your landscaping, flowerbeds and garden will look better than ever.