Here are some strategies for preparing turf and winter ornamentals for extreme weather.
Turfgrassand ornamentals will soon be shivering in the North and the Midwest, according to the 2014-2015 Winter Weather Outlook developed by The Farmers Almanac. Their predictions anticipate very cold to frigid temperatures over a wide swath of the area combined with precipitation levels ranging from below-normal to near-normal for the plains and great lakes states to “copious” in the northeast.
While the specific source of its predictions is never revealed, many old-timers rank its accuracy over the years as close to 80 percent – a lot better than a coin toss. To review the full Farmers Almanac outlook, go to http://farmersalmanac.com/weather/2014/08/24/2015-us-winter-forecast.
The primary source for daily scientific forecasts is the National Weather Service (NWS) National Oceanic and Atmospheric Administration (NOAA). Just go to http://www.weather.gov and enter your state, city or zip code. It’s a 24/7 resource, more up-to-date than the broadcast news and without the additional chatter.
Longer-range information, such as the Winter Weather Outlook, is issued by the NWS’s National Center for Environmental Prediction (NCEP) through its National Climate Data Center. These forecasts are posted monthly at http://www.cpc.ncep.noaa.gov.
Winter in the north and central regions: what to expect
Long-range forecasts for much of the north and central regions are ambiguous this year. Low temperatures and high precipitation predictions are listed for some areas. In other areas, the listing is for an equal chance of both factors being either above or below average.
The NCEP is also the primary source for other major weather issues, such as hurricanes and tsunamis, and for the El Niño Watch. Its September report puts the chance of El Niño at 60 to 65 percent during fall and winter for the Northern Hemisphere.
The National Drought Mitigation Center is the most complete resource for drought condition assessments and outlooks and for drought impacts. The link to all that information consolidated on the U.S. Drought Monitor map is http://droughtmonitor.unl.edu.
Where To Get Your Weather Data
Many local media stations combine National Weather Service information with their own resources to produce their weather reports. Some stations offer links to their information either through streaming of their on-air segments or connections to their constantly changing forecast models, or both. Pick the source with the strongest accuracy rate and channel the information to your computer, tablet or smartphone.
The best updates of the impact of weather conditions on lawns and landscapes come through the local extension service. Some university extension services have even developed special sections geared toward green industry professionals. In many cases, you can sign up for the periodic updates via emails, blog links, texts or tweets. When concerns develop, you can communicate directly with turfgrass or ornamental specialists by phone or email.
Though the coming winter is still just a prediction, looking back at the last few years may give some indication of what to expect. In both the central and northern regions, winters varied greatly, with areas that were too wet or too dry and/or experienced extreme cold or wild temperature fluctuations.
If adverse conditions repeat, no matter what precautions you’ve taken, some of your clients are destined to have problems. So be prepared for a flurry of customer calls next spring. While winter damage is obvious to you as a lawn care professional, your customers may need help recognizing it.
Tips for turf
You can’t control the weather, but you can prepare for it.
Preparation starts with basic agronomics, notes Dr. Brad Fresenburg, assistant extension professor/extension turfgrass specialist, University of Missouri. Take a soil sample and follow the recommendations given in the test results. When you get the pH, phosphorus and potassium levels right, all plants have better odds of standing up to adverse conditions.
“Potassium helps the plants harden off and prepare for winter,” Fresenburg says. “But if you have an adequate amount in the soil, you don’t need to apply more.” If you’re fertilizing in the fall, monitor the amount of nitrogen and the source. Pushing late-season vegetative growth can reduce the plants’ carbohydrate reserves. Additionally, Fresenburg cautions against late fall nitrogen applications for those in the transition zone dealing with warm-season grasses.
Early fall is the ideal time for aeration and overseeding with cool-season grasses. “Watch the timing for your region,” Fresenburg says. “Aeration too late in the season can increase turf’s exposure to desiccation when there’s little snow cover during cold periods with very strong winds.”
He recommends maintaining a higher height of cut year-round for cool-season grasses, 3.5 to 4 inches on turf-type fescues and on bluegrass mixes. “The taller turf provides a shaded effect to deter fall and spring weeds,” Fresenburg says. “The roots grow a bit deeper, too. The only time to drop cool-season height of cut is for early fall overseeding to get the seed through the canopy to the soil.”
Photo: The National Drought Mitigation Center
In some regions, where cool, very wet springs prevail, turf maintenance professionals suggest a lower height of grass cut in late fall to avoid overly tall, matted turf for the first mowing the following spring. Some also are using mowing to turn fallen leaves to the equivalent of a light layer of fine-textured mulch across the lawn. The key is monitoring the depth to prevent too heavy a layer in any one spot.
“Early winter dormant seeding is not an option for regions that don’t stay frozen throughout the winter,” Fresenburg says. “For Missouri, the best timing for dormant seeding is late February or early March. That allows the freeze/thaw cycle to go to work for you, moving the seed into place to germinate and grow when soil temperatures warm.”
Disease issues also can be a problem, with preventive treatments for snow mold often required.
Water is such a valuable and often costly resource, so irrigation system efficiency is essential. Introduce your customers to the advances in technology and assist them in selecting the most appropriate new system – or upgrade an existing system – to meet their needs and conserve water.
Tips for ornamentals
Ornamentals require more individualized care than turf, though soil testing and adjusting fertilization and irrigation do apply. Watch the pruning schedules to avoid a late season flush of growth.
Heavy snowfall before fall leaf drop can be quite devastating to deciduous trees and shrubs. Lack of adequate snow cover combined with cold temperatures and strong winds can be brutal for all ornamental plants in the landscape. Erratic freeze/thaw cycles in early spring, especially multiple days well above freezing followed by a sudden hard freeze, can be equally damaging.
Caution customers who want ornamental plants that are pushing zone limits prior to planting, when possible. Recommend protective mulching for those already planted. Or, convince them to adopt the approach taken by Dr. Michael Goatley, turfgrass extension specialist/professor, crop and soil environmental science at Virginia Tech. “I plant what I like and enjoy it while it thrives,” he says. “And, if it can’t withstand the winter, I try something else.”
Suz Trusty is a partner with her husband, Steve, at Trusty & Associates, Council Bluffs, Iowa. She has been involved in the green industry for more than 40 years. Contact her at firstname.lastname@example.org.