Weeds, Thatch, and Aeration

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Treating your lawn for insects isn’t the only preventive step you can take in the spring. The cold temperatures severely limit the effectiveness of almost every herbicide (so don’t bother trying to kill your dandelions until the daytime temperatures reach at least 70˚-75˚). However, the weather of early spring offers perfect conditions for applying a preemergent to stop the weeds in your lawn before they start.

The one thing to remember with preemergent herbicides is that unless you have a serious problem with these types of weeds, the cost usually outweighs the benefits. If you had spurge, chickweed, or crabgrass taking over areas of your parking strip or lawn this fall, the All Seasons Barricade will prevent the seed of these pesky weeds from germinating and infesting your lawn again this year. Generally, this herbicide will last from 6-8 weeks and should be applied so that it can reach its peak effectiveness when the weed seeds are germinating (usually in April). Gallery, a broadleaf preemergent, prevents dandelions, mallow, and other broadleaf weeds from germinating. Unlike the others, Gallery lasts up to 9 months, and can be applied in early spring or late fall. Again, try and assess the seriousness of your weed problem, then consult with your local garden center to find the product that best suits your needs.

Second, you can spray your lawn with a broadleaf herbicide. Trimec has always worked well for me, but there are many other excellent herbicides that will eliminate broadleaf weeds without damaging your grass. For really hard to kill weeds, such as morning glory and wild violets, you will have excellent results with Triclopyr (Turflon Ester). The newest product on the market is a weed killer called Weed Free Zone. This is an excellent product if you want to kill all kinds of weeds, even the hard to kill ones, and not pay as much. Remember, however, that most herbicides for your lawn work best when the temperature is above 65-70˚, but does not exceed 85˚. Also, the weed killer must stay on for at least 24 hours without being washed off to remain fully effective.

Third, you can apply a weed-and-feed. This is by far the easiest way to fertilize and kill weeds, but it needs to be timed just right to work properly. The grass must be damp when it is applied, so that the herbicide will stick to the weeds. Leave it on for 24 to 48 hours, then water it in to wash the fertilizer off the grass and into the soil. If you decide not to use a weed-and-feed, May is an excellent time to apply your second dose of fertilizer. Sprays and weed-and-feeds and pre-emergents can definitely alleviate some hard work, but these products are only aids to help the gardener in the never-ending war against weeds. Don’t expect miracles. A hoe, gloves, and a pair of hands (the more pairs the better) are still the best weapons against weeds. They’re fairly cheap too.


One common problem for many homeowners in Cache Valley is thatch. So what is thatch? Most lawns will normally show some scattered, dried-up grass clippings, or brown patches, but don’t worry, these are not thatch problems. To identify thatch (a visible, thin layer of dead, decomposing grass clippings just under the grass, on the surface of the soil), you must look closely at the turf itself. A thin layer of thatch (about1/8 to 1/4 inch deep) is beneficial. Too much thatch (1/2 inch or more), however, can create problems, such as, promote disease, reduce the effectiveness of fertilizers and pesticides, and prevent water and light penetration.

Normally, the only recourse for thatch is the power-rake, which can damage your turf. Another way to get rid of thatch is to apply humate, or humic acid, that naturally “composts” thatch right in your lawn. Humates contain all the trace minerals and nutritional substances not found in chemical fertilizers (such as organic matter, carbon, protein, chlorophyll, and humic acid) necessary to the development of plant life. They also serve as a home for microorganisms. These microorganisms are the culprits that actually convert the thatch grass clippings and organic matter in your lawn into soil. Not only do they compost your thatch, but they also free up unavailable nutrients in your soil, increase water retention, assist in soil aeration, improve seed germination, and enhance root development.

Aeration and Humate

One problem spot you commonly see around the valley is sloped turf. If you have lawn on a slope that keeps burning up because the water just runs off of it instead of soaking in, you might want to consider aerating. The water must get down to the roots and aeration will provide a way for that moisture to penetrate hard, sloped soil. The best time to aerate is in the fall when your grass is going dormant and not actively growing, which in turn will cause less damage to the roots. Humate has also proven very effective against dry conditions, and you will find your turf holding in more moisture. Also, if your soil has a lot of clay, aerating once a year for about 3 or 4 years will help break up the clay and let in more water and oxygen into the root system.