Winterize your lawn
Amy Jordan
Originally published 01:04 p.m., November 1, 2007
Updated 01:04 p.m., November 1, 2007
It’s an important time to fertilize cool-season lawns such as tall fescue to have a great looking lawn late in the year, and earlier green-up and thicker growth next spring.
Its also an excellent time of year to control lawn weeds.
Plants are still using sunlight to make food energy (photosynthesis). Since there is little demand for growth, any food produced is moved to turfgrass roots and crowns where it can be stored for the winter to sustain plant metabolic activity. It will also provide an immediate and plentiful food source when plants begin to grow in spring, so turfgrasses thrive through March and April without any extra nitrogen. Early spring nitrogen fertilization can promote excessive shoot growth and weaken the plant going into summer. November-applied nitrogen can help with winter hardiness, root growth, and shoot density, leading to a great start next spring.
There are many formulations of lawn fertilizer available and it is often difficult to decide which one is best, when in fact they are probably very similar.
“Winterizer” products typically have a higher percentage of potassium (third number on the bag) than other lawn fertilizers. Potassium is an element associated with stress tolerance. Most Kansas soils contain sufficient levels of potassium, so additional applications of this element are not usually necessary.
Nitrogen (the first number on the bag) is the element most needed by turfgrass. An important consideration when choosing fertilizers is the availability of the nitrogen source. At this time of year a quick release form of nitrogen is important so that the turfgrass plants can metabolize the fertilizer before they go dormant. Read the label on the bag of fertilizer to determine how much of the nitrogen source is released quickly or slowly.
Now is also an important time to control broadleaf weeds such as dandelions, henbit, and chickweed. These weeds are more easily controlled now than in the spring because they are actively moving materials from the top portion of the plant to the roots. Herbicides will translocate to the roots as well and will kill the plant from the roots up. Be sure to choose a day that is 50 degrees or over. The better the weed is growing, the more weed killer will be moved from the leaves to the roots. Cold temperatures will slow or stop this process.
The “weed and feed” fertilizer/herbicide combination products could be used to at this time of year if you have a significant broadleaf weed problem. This product will supply the needed nitrogen, so an additional application of fertilizer is not necessary. Be sure to carefully read the label before application. With most of these products, the foliage should be wet when applied so the herbicide will stick to the leaves.