Welcome to our March edition and our third and final series on preparing our yards for spring. Based upon the title, I should be talking more about the growth of lawns and plants; however, for healthy lawns and plants, irrigation is a major component. We can apply all the fertilizer we want, prune the plants, aerate our lawns, etc., but if the irrigation is not right, the results at best are fair and at worse, we have dead plants and lawns. So growth has everything to do with irrigation, and proper irrigation has everything to do with the topics we have been covering. Also please note that this is Part III; I would recommend that you read Part I and II. The articles are on my website at www.executivecareinc.com under publications or on Home Improvement & Remodeling Magazine’s website at www.HomeImprovement-Magazine.com. With that covered, let’s start.
Last month, we left two items under lawn sprinklers not covered: seals and “sinking sprinklers.” Seals are a very important part of the sprinkler, and each manufacture has its way of designing them into the sprinklers. For example, Rain Bird’s seal is incorporated into the cap of the sprinkler. If you look at a
Rain Bird sprinkler, the top has a white inner ring. This is the seal, and as the “pop-up” part of the sprinkler rises, this seal prevents water from coming out. When the seal becomes aged via use and sun, it no longer seals, and water can be seen leaking out along the edge of the pop-up and seal. If not changed
out, the leaking will increase to the point of becoming a small stream of water, which not only wastes water, but it prevents the pop-up from fully rising and the nozzle from watering the full distance. Toro sprinklers have their seal as a separate piece, under the cap. The cap must be removed to be
able to exchange the seal. Combined with the seal is a retainer that holds the seal in place, so there are two pieces, but the rubberized one is the seal. Only if the retainer is damaged would you need to replace it; otherwise, it’s fairly permanent. The Toro seal, as the Rain Bird seal, becomes hardened through use, no longer sealing, and water can be seen coming from the base of the pop-up. Checking and exchanging seals is virtually never considered by the homeowner, mostly for a lack of awareness of how important this is
to do. Seals in general last between three to five years before they need to be changed. It is a simple process requiring two channel-lock wenches—one for unscrewing the cap and one for gently holding the sprinkler body. These seals often cost the same price as buying a complete sprinkler, so if you are not close to a sprinkler store where you can buy just the seals, the box stores sell the whole sprinkler that you can dismantle and use the seal or just swap out the sprinkler.
The second item is “sinking sprinklers.” Now we know sprinklers do not literally sink, though visually it appears as such. Year after year, less of the “pop-up” portion is visible, and in some cases, this pop-up portion is only an inch or two above the lawn. At this height, it cannot water without the lawn blades interfering, blocking the spray and causing poor coverage during watering, especially a few days prior to mowing, when the lawn is the tallest. So if the sprinklers can’t “sink,” what is happening? It is called thatch. It is most prevalent in lawns that are overwatered and fed high nitrogen. It is the accumulation of dead lawn that develops below the growing portion of the lawn, causing it to rise up. When a lawn has excessive thatch, it becomes a “high-maintenance” lawn, requiring more fertilizer, more water (which adds to the problem), and more chemicals to treat because it becomes more subject to infestation and diseases. Also it requires the lifting of the sprinklers by adding extension risers and couplers. So what can be done? For the lawn to get to this point, it required several years of overwatering and high nitrogen. Getting back to an acceptable thatch level of one-half inch or less will require several years of purposeful care. Rental yards have what is called a “dethatcher,” which is comprised of tiny little blades (not sharp) that spin at a high speed, “beating up” the lawn, and thereby pulling out the dead lawn matter from the base. If you can imagine a high-powered electrical rake, it is much like that. And because of the violent action that is used, thatch reduction must be done over a period of time, allowing the lawn to recuperate and heal itself. The best time to do this is early spring and early fall. About two weeks prior to dethatching, apply a moderate amount of 15-15-15 fertilizer (leaves/roots/cell structure is to what each number corresponds). Apply the fertilizer moderately, remembering that overdoing the fertilizer was one of the contributors to this problem. You can expect that each time the lawn is dethatched, between one-fourth inch to one-half inch of dead-lawn matter will be removed. If the thatch is one and one-half inches tall, it will require two to three separate attempts to remove it. If you use pre-emergent to control lawn weeds, apply this after dethatching. Once the thatch has been reduced, you will find the lawn returning to a healthy state and will be easier to mow and to maintain.
This concludes our lawn-care tips. As always, I hope I have helped. If you need assistance in implementing these tips or any of the tips mentioned in the prior articles, please do not hesitate to call. Spring, one of our more busier times, has started early with our warmer temperatures. So if you need help, or are planning to landscape or re-landscape your yard, I would suggest that you call sooner if possible, rather than later for an appointment.
Thank you and Good Gardening!