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Steps for a Health "Organic Lawn"
Barbara J. Bromley, RCE of Mercer County, Horticulturist
Residential lawns have a reputation for being high maintenance, chemical-requiring, water-guzzling, environmentally irresponsible luxuries requiring great expenditures of time and money. This is a misconception. Lawns are a beautifying link between the home and landscape, provide a play surface, reduce soil erosion, supply oxygen, have a cooling effect on nearby areas, and add to property value. Actually there is a happy medium. There are ways to maintain a healthy, low maintenance turf on any New Jersey soil with a minimum of chemical and labor input.
01. Accept a slightly lower standard for the lawn. "Perfect" is a nearly impossible standard for a lawn, especially if pesticides are not regularly used. Accepting a few weeds or a lawn with different shades of green or the presence of a few insects is far more practical. Commercial lawn care customers requesting "natural" care should be informed of this balance.
02. Select the right grasses for the site and program. By choosing the right grasses, many long-term problems can be avoided. There is a tremendous amount of diversity in today's available cool season grasses. Many Kentucky bluegrass varieties and all perennial ryegrasses are relatively high maintenance. The fine and tall fescues tolerate moderate shade and drought. Poa trivialis, roughstalk bluegrass, grows well in damp sun or shade. Established hard fescue does not require fertilization or as much mowing as perennial rye, bluegrass, or some tall fescues. Many perennial ryes and fescues are endophyte-enhanced to reduce damage by surface feeding insects. The advantages and disadvantages go on and on. Blends of grass species and mixes of varieties lend more diversity to a lawn and reduce the impact of insect and disease infestation. Even buffalo grass and zoysia may be useful on some sites.
03. Improve the soil. Having a deep rich sandy loam with 5% organic matter and 50% air- and water-containing pore space is great, but not everyone is so lucky. Soil improvement prior to planting, including the addition of organic matter, and occasional core aerifying of established lawns helps make the soil environment conducive to good rooting.
04. Apply fertilizers and lime properly. Everyone should have a soil test to establish the base for pH and nutrient levels. Liming (or not) or applying just any old lawn fertilizer without a soil test can result in undesirable nutrient deficiencies or excesses. There is also the concept that applying nothing at all to a lawn is more environmentally responsible. For most grasses some nutrient application will improve the stand of grass and prevent weed encroachment or grass thinning and subsequent soil erosion.
Organic nitrogen sources such as well-rotted (not fresh) manures or feather meal are slow-release, do not burn the grass, and stimulate slow, even growth. There is research evidence that slow-release nitrogen use generates fewer grass clippings and therefore less mowing. If minimum fertilization is desired, labor Day (or thereabouts) is the best time to take a single application to stimulate deep rooting and enhance winter hardiness. A second application may be made (if needed) on Thanksgiving or Mother's Day (or thereabouts).
If the grass clippings are left on the lawn (a must with organic growers), this reduces the amount of additional fertilizer needed by 30% to 50%. The nutrients in the grass are returned to the soil. I grass is mowed often enough, the mulching blades will finely chop up the clippings so they are practically invisible. And leaving clippings does not contribute to thatch buildup.
05. Mow properly Mowing too short, a.k.a. "gold course syndrome," or maintaining a regular mowing height below 2 inches is a stress for residential turf. Mowing is one of the most time consuming elements of yard work. Some assume that if the lawn is mowed shorter, it won't have to be mowed as often. The opposite is true. The shorter the mowing, the more frequently it must be done. Ideally, most residential mowing should be no shorter than 2 1/2" in spring and fall and 3" or higher in summer. Also, mow often enough so no more than 1/3 of the grass blade is removed each time. This may mean mowing more often than once a week.
06. Water correctly. Most years no supplementary irrigation is needed on low maintenance turf. If a drought period exceeds five or six weeks, then laws can be watered only to rehydrate the dormant grass crowns, not to bring the grass out of dormancy. When water is needed, irrigate in early morning (5-7 am) when grass blades are already wet from dew to help reduce disease problems. Also, shallow, infrequent water stimulates shallow rooting. Watering 1 to 1 1/2" per week on moderate to high maintenance turf helps promote deeper roots.
07. Identify problems and correct them promptly. When a problem arises, identify the cause. If it can't be corrected with biological, cultural, mechanical, or physical means, or with non- or low -toxicity controls, simply repair the damage by reseeding or sodding as soon as possible.
08. Time maintenance activities for the most appropriate season. It's called "Labor Day" because that is when you work on your lawn. Seriously, time lawn work to correspond with good growing conditions for cool season grasses. Seeding can be done any time, but the last week in August or first week in September is ideal. Overseeding on frozen or "honeycomb" ground in February or early March is also okay.
09. Consider alternatives to turf grasses in very shady sites. There are mosses, ground covers, and mulches that are better adapted to very shady locations than grasses (when was the last time you saw grass growing in the woods?) In light to partially shaded conditions, fine and tall fescues are a good choice.
10. Ask Questions. Use reliable reference sources. Consult your Rutgers Cooperative Extension office and libraries for grass varieties, culture and other information about responsible lawn care.
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