The Importance of Good Lawn Drainage
Good lawn drainage is imperative for lawn health. Drainage affects a variety of plant functions including metabolism, photosynthesis, and root health, as well as pest and disease resistance. When you read books, websites and extension pamphlets about plants, you often see that to diagnose a plant problem, first you start with the roots. If the roots are healthy, the rest of the plant has a better chance of being healthy. When the roots have problems, the rest of the plant will be affected. Roots in soil with poor drainage can rot. Wet conditions and lack of air provides an ideal place for growth of disease-causing bacteria. Additionally, if water fills all of the spaces near roots that generally hold air, the roots cannot take in oxygen, which is necessary for the metabolic processes through which plants break down the sugars they have produced during photosynthesis.
Factors Affecting Lawn DrainageSeveral factors affect the quality of lawn drainage. The soil type is one of the greatest factors. Soil that is high in clay, but low in sand or organic matter will have poor drainage. The molecules in heavy clay soils are close together, providing few spaces for air and water to move around. In clay soils, drainage is slow to non-existent. Very sandy soils have the opposite problem. They drain quickly-sometimes too quickly. Plants that are not well adapted to sandy soils, and like to stay on the dry side do not do well in sandy soils that drain quickly. Sandy soils also leach nutrients quickly because of their rapid drainage. The sand particles do not easily hold on to nutrients and frequent rushing of water carries nutrients out of the soil as it quickly drains. Another factor that affects lawn drainage is soil compaction. Soils that sustain heavy foot traffic consistently become compacted-literally pushing the soil particles together and squeezing out any spaces for air and water movement. Compaction can cause lawn drainage problems by prohibiting water from penetrating the soil in the first place.
How to Improve Lawn DrainageIf your lawn is poorly drained, all is not lost. You can alleviate lawn drainage problems with a few steps. The first step to improving lawn drainage is to aerate the lawn. The best aeration is done with a punch-core aerator that actually removes cores of soil, rather than pushing the soil further into the ground. The act of aerating in and of itself will add air pockets. To improve the soil drainage long-term, the next step is to top-dress the soil with a compost/topsoil or compost/sand blend. This will gradually introduce more organic matter into the soil, which will improve the drainage long-term. Organic matter works both to hold water and improve drainage. The unique properties of compost for improving drainage have not yet been replicated by any man-made substance. Because of these dual properties, addition of compost to your lawn soil will solve lawn drainage problems for both sandy soils and soils with heavy clay content. For healthy turf, you must pay careful attention to your lawn drainage. If necessary, take the steps described above to solve lawn drainage problems and improve your lawn for the long term.