Turfgrass Frustration in Central Virginia
Central Virginia is simply not a satisfying place to grow a grass lawn. This is frustrating for all of us, but especially for those new to the area. I spoke with the Master Gardener Program Chair for the Healthy Virginia Lawn Program in Albemarle County, Diane Lowe, who says she often hears, “I never had trouble growing grass in Michigan, Ohio, Illinois, etc.” Says Diane, “Boy, if I had a nickel for every time I heard this!”
The problem can’t be blamed solely on our acidic, clay soil. Mostly, it’s the fact that newcomers have landed in the dreaded “transition zone” of the grass-growing world — too cool for warm- season grass varieties, and too hot for cool-season grasses, which tend to go dormant in our summer heat. Our area just doesn’t provide the right conditions for either warm-season or cool-season varieties of grass. No wonder it’s frustrating.
Here in the transition zone, most of us are growing (or trying to grow) one of the cool-season varieties of grass — typically, tall fescue or Kentucky bluegrass. The warm-season grasses, such as zoysia grass, will go dormant during our cold winters, but that’s a reasonable trade-off for some people. My neighbors have a zoysia lawn in their kids’ play area, and it is thicker and healthier-looking than any other lawn around — but it turns brown in winter. If, like most of us, you have a tall fescue lawn, it has a tough time with our hot summers and with our clay soil, especially if it’s compacted. As a result, it often gets thin and is vulnerable to weed invasions. Those of us who’ve been struggling in the transition zone for years can feel your pain, Newbies. But there are a few things you CAN do to improve your turf.
Perhaps one of the most important steps you can take to improve your lawn is to work on your lawn primarily in the fall, not the spring. The experts at the Virginia Cooperative Extension are on a mission to get us homeowners to stop focusing on our lawns in the spring and to switch our lawn-related efforts to the fall. This Extension article — “Breaking the Spring Seeding Cycle” — is well worth a read. ext.vt.edu//turfandgardentips/tips. And the cease-and-desist efforts are directed not just at spring grass seeding, but also at fertilizing and weed control. Apparently, it’s just natural for us to emerge from winter and gaze expectantly at our lawns, eager to green them up and ready them for picnics and ball games. However natural it may feel, it’s the wrong season for these activities, despite the presence of lawn seed and fertilizer at the garden stores!
September is the pefect time to work on your lawn. Fall is the season to improve your soil and to fertilize, if needed. Take a look at this helpful Maintenance Calendar for Cool-Season Turfgrass Lawns in Virginia: VaTech/edu/Pub. No. 430-523. It indicates the proper times to fertilize and to use a pre-emergent or post-emergent weed herbicide, if you’ve decided to do this. There’s a maintenance calendar for warm-season grasses as well. pubs.ext.vt.edu/Pub.No.430-522 (2014).
By the way, if you’re looking for an alternative to the standard lawn weed treatment — the chemical herbicide 2,4-D — you’ll be interested in new iron-based herbicides whose active ingredient is simply chelated iron — the same thing that is used to treat iron deficiency in plants. Apparently grass can tolerate an overdose of iron, but most weeds can’t. Check out this new kind of weed treatment for lawns in “Iron-Based Herbicides: Alternative Materials for Weed Control in Landscapes and Lawns,” Univ.Md.Extension.umd.edu/md.edu
Spread Compost on your Lawn
Yup, you read that correctly; compost ON your lawn. Spread as little as ¼ inch (not more than 1/2 inch) of compost on your lawn twice a year, and your soil — and as a result, your turf grass — will gradually improve dramatically. Compost will improve your soil’s structure, reducing compaction and enhancing moisture retention, and because it contains nutrients normally found in fertilizer, it will reduce the need to fertilize, thereby reducing fertilizer run-off, a menace to our ecosystems. To learn more about lawn composting, watch this brief video prepared by a turfgrass expert at Va. Tech. ext.vt.edu/lawn-garden/turfandgardentips/pete-dye/index.html. This is an entire series of lawn care videos entitled “A Lawn to Dye For” that were prepared at Tech’s Pete Dye Golf Course, and all are worth viewing. You’ll have to scroll down a bit to find the one on lawn composting.
Spread lime, if needed. Spreading lime on the lawn is a regular task in this area because our soils tend to be acid — not the optimum pH for most turfgrass — and dolomitic limestone increases the soil pH to make soil more alkaline. A soil test will tell you how much lime your lawn soil needs so that necessary nutrients are actually available to the grass.
Proper fertilization will indeed help your grass, but the best time to fertilize is fall. That’s because “fall presents growing conditions conducive for improving turf density through the development of new shoots and stems, increased carbohydrate storage (i.e., food for the plant), and enhanced root production.” Va.Tech.Ext. Pub. No.430-520/FallLawnCare. So fall is THE time to thicken your cool-season lawn! And thicker turf will just naturally keep the weeds down.
Keep in mind, however, that your grass is actually just a whole lot of plants, and like any plant, it will thrive only in soil that suits its needs. Too many of us assume that when it comes to fertilizer, “If a little bit is good, twice as much is better.” NOT TRUE! Before you fertilize, collect some soil samples in your yard and order a soil test from the Virginia Extension Office (Get the little soil sample box you need and directions at the local Extension Office, Fifth St. Extended Building, 460 Stagecoach Rd, Charlottesville). If it’s been three years or more since you had your lawn soil tested, you’re due!
The soil test report provided by the experts at Va. Tech’s Soil Testing Lab will tell you what nutrients your soil is lacking and if it needs lime and/or fertilizer in order for your turfgrass to thrive. Getting these amounts right is critical to success, and also to the health of our rivers and lakes. Ext.VaTech.edu/Pub. No. 426-059/”Groundwater Quality and the Use of Lawn and Garden Chemicals by Homeowners” A soil test of your lawn soil will measure and makes recommendations for the following major nutrients needed by turfgrass: P (phosphorus); K (potassium); Ca (Calcium); Mg (Magnesium) and five micronutrients. In addition, the test determines the soil pH and makes recommendations on how to raise or lower the pH. The nitrogen (N) requirements for turfgrass cannot be reliably determined by a soil test, but the report will nevertheless contain a nitrogen recommendation for the kind of grass being grown. Thus, the report will tell you exactly what to add so that your soil can feed your grass without damaging our water supply with fertilizer run-off.
For detailed information on meeting the nitrogen needs of a lawn, how to calculate amounts of nitrogen and properly spread them, you’ll want to look at Ext/VaTech/LawnFertilizationVirginia. I’ll warn you now, there’s math involved! Virginia Tech recommends 0.7 lbs of Nitrogen per 1,000 sq. ft — twice in the fall. If, like me, you avoid math like a plague, you can simplify this calculation by using the older recommendation of 1.0 lbs N/1000 sq. ft. in the fall (the N stands for nitrogen).
But you can avoid these calculations by using the Healthy Virginia Lawn service, which does the calculating for you! It provides clients with the exact amount of a specific fertilizer they need based on their total square footage of lawn and the soil test recommendations from Va. Tech. So for example, you might be told to spread 140 lbs of a 16-4-8 fertilizer two times, 4-6 weeks apart, in the fall. If this sounds good to you, can can sign up for a consultation with the Healthy Virginia Lawns program. For more information, call 434-872-4580 or email firstname.lastname@example.org. Here’s a link to the brochure. Healthy Va. Lawns Brochure.
Remember, those three numbers on a bag of fertilizer stand for the percent by weight of nitrogen, phosphate (for phosphorus), and potash (for potassium) in the fertilizer. Mature lawns often have adequate levels of phosphorus and potassium, so maintenance fertilizers containing only nitrogen are often used on these lawns.
Because cool-season grasses are actively growing in the fall, it’s a good time to aerate your lawn, especially in heavy traffic sections and other compacted areas. Soil compaction hinders the grass’s root development because it physically restricts root penetration and reduces the oxygen levels required in the soil for root development. Core aeration (removing plugs from the soil is a standard method for improving soil aeration. Now’s the time to do it! VaTechExt./Pub No. 430-520/FallLawnCare.
Use the resources and services of the Virginia Extension Service at Virginia Tech. The resources directed at lawn and turfgrass issues through the Virginia Extension Service are extensive. For any question you may have, you’re likely to find help on the Extension website. For example, if you’re wondering if your lawn spreader is properly calibrated, you’ll find help at pubs.ext.vt.edu/Pub. No.430-017/”Calibrating your Lawn Spreader”. For the list of publications that address lawn and turfgrass, see pubs.ext.vt.edu/category/lawns.
“Fall Lawn Care,” pubs.ext.vt.edu/Pub.No. 430-520
“A Virginian’s Year-Round Guide to Yard Care: Tips and Techniques for Healthy Lawns and Gardens,” www.dcr.virginia.gov/soil-and-water/document/yardcare.pdf (Va.Dept.of Conservation & Recreation).
“What Grass Should I Grow for my Lawn,” Va.Tech.edu/newsletter-archive/cses/2008-03
“Establishing Lawns,” pubs.ext.vt.edu/Pub.No.426-718.pdf
“Lawn Fertilization in Virginia,” pubs.ext.vt.edu/CSES-135