There is a little nip in the air, indicating the approach of fall. This means its time to begin winter preparations for your yard and garden. In this process, the lawn sometimes gets ignored because it stops growing and seems to present few demands. However, fall is a key time of the year in lawn growth, and you can have a definite impact on how it looks next spring if you take time to complete a few simple tasks.
Cleaning up leaves is more than making the lawn look nice. If left on the ground during the winter, leaves become wet, mat down, and smother the grass during the winter. Grass does not completely stop growing, even in the dead of winter. As it grows, grass needs to breath and matted down leaves reduces air flow. Leaves also cause quite a bit of shading during the fall and early winter before snowfall when the grass is trying to store up energy. Just as chipmunks store food underground for the winter, grass uses sunlight to make food, which it stores in its stems growing underground. If you have just a few leaves and a mulching mower, mulching the leaves and letting them filter into the grass is fine as long as they are not too thick.
Speaking of mowing, it is a good idea to continue mowing your lawn well into October and maybe even into November. These late mowings will not only help chop up any leaves you may have missed, but more importantly, will help prevent winter diseases. You may have heard the advice to lower the mowing height a notch or two on your last mowing. This can help alleviate disease, but be careful not to overdo it. You are better off to leave the mowing height the same, but mow more often into late fall instead.
Fertilizing during late fall also is a good idea since the grass, as we mentioned above, is still growing underground, even though leaf growth has slowed considerably or stopped. Since the underground part of grass is what allows it to make it through the cold winter and green up in the spring, a light late fall application is a good idea. Again, be careful not to overdo it. Apply no more than 1 lb of nitrogen (N) per 1000 ft2.
If you have an automatic irrigation system and have not touched the timer since the summer months, now is the time to do so. Grass uses much less water in the fall than during the heat of the summer, less than half as much. That means you may need to irrigate your lawn only about every 10 days depending on soil type. Depending on your location, you may want to irrigate your lawn until the end of October or even into the second week of November. In colder areas of Idaho, freezing temperatures may dictate stopping irrigation before the end of October. A final deep watering just before you winterize your irrigation system is a good idea. This will help prevent winter desiccation damage to your lawn especially if we have a winter without much snow cover.
What about controlling those troublesome perennial weeds like dandelions? Fall is the best time to kill them. As with the grass, perennial weeds are preparing for winter and sending food reserves underground. Applying herbicide around the time of the first fall frost will be most effective.
Following these year-end practices will help to ensure winter survival and improve the lawn’s appearance next year.