The first step in switching from conventional to natural organic lawn care is to assess the quality of the existing lawn. If an existing lawn contains few weeds and consists of desirable turfgrass species, natural organic methods and cultural practices can maintain a satisfactory lawn. However, if a lawn has excessive weeds and/or consists of undesirable turfgrass species, it is best to kill the entire lawn and start over. After this decision has been made, the next step is to assess soil quality.
Natural organic gardening and lawn care methods underscore the importance of good soil quality as a primary factor in growing healthy turfgrass. Good soil contains adequate organic matter, which improves soil structure by binding mineral soil particles together to form aggregates. This creates greater pore space among the aggregated particles, providing optimal conditions for root growth. Increased pore space improves both soil drainage and water-holding capacity and also improves soil aeration. In addition, sufficient quantities of organic matter in the soil aid in nitrogen fixation, help reduce soilborne plant diseases, and help hold nutrients for plant use. Good soil also contains adequate amounts of the nutrients plants need.
A useful tool in the assessment of soil quality is a soil test performed at a soil-testing lab. Most tests will measure pH and various nutrient levels. Also included will be recommendations for chemical fertilizer application to correct any deficiencies. Organic matter tests are usually available as an option and measure the percentage of organic matter in the soil. In Ohio, 4-6% organic matter in the soil is considered satisfactory.
If an existing lawn is to be preserved, the transition to natural organic methods can be instituted at any time. See the "Natural Organic Lawn Care Calendar for Ohio" at the end of this fact sheet for details. When it is time to fertilize, choose appropriate organic fertilizers to correct deficiencies. Although soil test recommendations are based on the use of chemical fertilizers, use the nutrient rates recommended as a guideline for the application of natural organic fertilizers. More information on fertilization will be found in the "Maintenance" section.
An existing lawn of poor quality may need to be killed and re-established. Killing a lawn may involve use of a non-selective herbicide. The use of glyphosate (Roundup®) or glufosinate (Finale®) might be considered, as these do not leave residues in the soil. Tarping the lawn with plastic in summer heat can also be used the kill the existing grass, though this may be difficult to do based on the size of the lawn.
The advantages of starting a new lawn are: 1) grasses can be selected that require less nutrition and water, and that are resistant to insect and disease attack; 2) soil can be amended with organic matter; and 3) nutrient deficiencies can be corrected (per soil test) before seed is sown. Adding organic matter to the soil before seeding is more effective in changing the percentage of organic matter in the soil than top-dressing an existing lawn with compost. Using appropriate turfgrasses, adding organic matter to soil, and correcting nutrient deficiencies will go a long way toward producing a healthy lawn that will be easy to maintain organically.
Cultural practices in natural organic lawn care are similar to those used in conventional lawn care and are described in the "Maintenance" section. Proper maintenance techniques and timing are more crucial in a natural organic lawn since the aim is to prevent potential problems.
There are two key points to keep in mind when going organic. The first is that compared to conventional lawn care, organic methods take longer to produce visible results in most cases. Since the organic approach stresses the ongoing building of soil, there are no quick fixes as promised by chemical fertilizers. Secondly, perfection is an unreasonable expectation. Tolerating a few weeds or insects here and there is part of the natural organic approach. When natural organic methods are used consistently over time, a reasonably uniform green lawn that is resistant to adverse environmental conditions and/or pests can be expected.
ABOUT THE AUTHORS
Jane C. Martin, Franklin County Horticulture Agent
Alyn Eickholt, Franklin County Master Gardener
Joanne Dole, Franklin County Master Gardener
Source: Natural Organic Lawn Care for Ohio
