   Installing Cool Season Sod - September 5, 2001 Jeff Schalau, County Director, Agent, Agriculture & Natural Resources Arizona Cooperative Extension, Yavapai County Before I launch into this week's topic, I cordially invite everyone to attend the Second Annual Arizona Highlands Garden Conference happening October 8 and 9, 2001 at Chapel Rock Conference Center in Prescott. The conference is being planned and coordinated by the Yavapai, Coconino, and Gila County Master Gardeners and will feature several talks, demonstrations, and concurrent sessions by statewide experts. Lunch and snacks will be provided on both days. An embroidered canvas tote bag and notebook are included. There will also be several exhibitors and door prizes. The cost of the two-day conference is $60 (before September 7). For more information, call 646-9113 or visit the conference web site at http://ag.arizona.edu/yavapai/. I look forward to seeing you there! Now for this week's topic. September is a good month to install cool season sod in the high deserts of central Arizona. Cool season grasses are those that are adapted to favorable growth during cool portions (60 deg. to 75 deg. F) of the growing season and become dormant during hot weather. Kentucky bluegrass and tall fescue are common cool season grasses planted in our area. Cool season blends are also planted. One such blend is a combination of Kentucky bluegrass, perennial rye, and fine fescue. Sod is a great way to create an area of turf in a very short time. However, if installed incorrectly, it can be a costly disappointment. The soil preparation is the same as that for a seeded lawn. Sod has several advantages: little if any annual weed problems, no losses due to birds stealing seed, and no gulleys or washouts. If Bermudagrass or perennial weeds are present, be sure to kill them with a suitable herbicide (glyphosate) and repeat the treatment as necessary. Prior to soil preparation, check out the irrigation system by checking for uniform coverage and/or leaks. Install a new one if needed. This will pay for itself in the long run. To prepare the soil for sod, remove surface and buried rocks and debris. Add a 3 inch layer of well composted organic matter over the area. Also add 8 pounds of ammonium sulfate per 1,000 square feet. You may also add sulfur (5 pounds per 1,000 square feet) to help neutralize soil alkalinity. Rototill organic matter and fertilizer into the soil to a depth of 4-5 inches. Rake and level the entire area giving it a smooth, even surface. The soil should then be rolled with a water-filled lawn roller. This will prevent the area from sinking in after the sod is installed. Level the area with a rake again if needed, then irrigate to a depth of 6 inches an allow it to soak in. Ideally, the sod is cut from the farm the night before and installed the following morning. If you are not purchasing the sod directly from the grower, get a guarantee from the vendor to ensure quality. Choose a starting point parallel to the longest straight edge of your yard and lay sod strips in a staggered fashion as if you're laying bricks. Edges and ends of sod should fit tightly and not overlap. Trim pieces so that they fit with a sharp knife. However, you should avoid cutting sod into short, narrow strips as these tend to dry out very quickly. Be gentle with the sod as you lay it and sprinkle it lightly with water to avoid drying. After laying, roll the sod again to squeeze out air pockets. Irrigate the sod immediately after installation. You may need to irrigate two or three times per day until roots are established. Be careful not to flood. Roots will not grow in waterlogged soils due to lack of oxygen. Two to three weeks later, irrigation frequency can be reduced and gradually shifted to less frequent deeper irrigation. Infrequent, deep soakings will best encourage your grass to develop a strong, deep root system. Do not walk on the sod for several weeks to aid in establishment. Early on, the goal is to encourage root penetration into the soil. Over time, deep root growth ensures healthier turf and conserves water over the long run. To determine an appropriate irrigation schedule, observe the time then start the sprinkler system. Monitor the depth of irrigation with a long screwdriver. When the soil is irrigated to a depth of 6 to 8 inches, check the time. This becomes the starting point for your irrigation schedule. As seasons change, this exercise should be repeated to adjust the irrigation schedule. Begin mowing your lawn in about two weeks. Rotary mowers are best suited to cool season grasses in home landscapes. Keep the mower blades sharp. Mow the lawn about once a week thereafter. You should never remove more than one-third the total height of the grass at any given time. If you need to remove more than one third, do it gradually giving it several days to recover before mowing again. After 4-6 weeks of growth, fertilize the turf. Apply one pound of actual nitrogen per 1,000 square feet of turf. Remember to check the guaranteed analysis on the fertilizer bag. For example, if you use ammonium sulfate (21-0-0), you will need to apply about 5 pounds per 1,000 square feet. I recommend using a rotary type spreader rather than a drop type spreader. Rotary spreaders disperse the fertilizer more widely and decrease the potential for burning caused by over application. For more information on cool season turf maintenance, see the September 27, 2000 Backyard Gardener column on the web site (see web address below). For installing warm season sod, simply follow the same steps, but plant during the month of June. The University of Arizona Cooperative Extension has publications and information on turf installation and maintenance. If you have other gardening questions, call the Master Gardener line in the Cottonwood office at 646-9113 or E-mail us at mgardener@kachina.net and be sure to include your address and phone number. Find past Backyard Gardener columns or submit column ideas at the Backyard Gardener web site: http://ag.arizona.edu/yavapai/anr/hort/byg/. |