Oxygen is essential for both the establishment of root systems and above-ground plant growth. The practice of increasing or restoring soil’s oxygen supply is known as aeration. Many homeowners may believe that aeration is only necessary for a healthy lawn, but in truth the entire landscape can benefit from increased access to oxygen. There are also several ways that a plant’s oxygen supply can be compromised, inhibiting further growth. Thatch (the covering of dead or mown grass across a lawn) is less easily broken up if there is not sufficient oxygen in the soil. The new landscaper must keep tabs on the oxygen level in the landscape, watching for dead spots or other areas that suggest soil compaction or loss of oxygen.
Ground-level areas with high foot or automobile traffic can become compacted due to the repetitive stress placed on the soil. This stress collapses the small pockets and passageways crafted in the soil by worms and microorganisms. After the pockets collapse, roots can neither penetrate the soil nor access the oxygen necessary for further growth. Excessive or repetitive stress is not the only source of de-oxygenation of the soil, however. Problems with drainage and nearness to the local water table may also cause major problems with the soil’s oxygen levels. As the water table rises—gradually getting closer to the surface—the amount of oxygen in the soil drops off dramatically. Severe drainage problems may have to be alleviated with major excavation, such as a pond or permanent culvert. Minor drainage issues can sometimes be corrected with simple planting beds or drainage ditches.
When considering solutions for aeration problems, landscapers have a number of different options depending on the size of the affected area. Smaller patches of compacted lawn may be aerated by a simple hand-operated aerator. These are inexpensive and available at many plant nurseries and garden centers. In addition to being cheap, these hand-operated aerators also offer excellent mobility for aerating in tight spaces (such as in flowerbeds or near other delicate plants). For larger swaths affected by compaction and poor oxygen supply, powered aerators may be needed. Local landscaping companies typically keep a variety of aerators—some of these may be available for rent. After the land has been successfully aerated, homeowners also need to take measures to prevent future aeration problems. If a piece of property is subjected to heavy foot or automobile traffic, regular aeration or a rotation of the activity will most likely be necessary. Heavy rainfall and potential drainage problems will also need to be addressed frequently if a more permanent solution—such as an excavated pond or culvert—is not implemented.
Tags: oxygen, aeration, soil, drainage, aerator, landscape