30 September 9, 2009
It has been a rough year for your lawn. After the winter, the moles had dug tunnels all over the lawn. Spring rains led to fungus diseases. Summer heat dried the lawn. All the while, most of us forgot to fertilize the lawn. September begins the start of one of the most important time of growth for your lawn. Let me explain why this is so.
As the cool temperatures of fall arrive, your lawn begins another time of rapid growth. Eventually, the weather gets really cold and the lawn goes to sleep for the winter. At least this is what we thought happened to our lawns. Researchers began to look closely at what happens to a lawn in the fall. After years of studying the growth of a lawn in the fall, they discovered that once all of the top growth slowed down in October, there was a lot of root growth going on. The roots that grow in late fall are the roots that have the potential to push up many new blades of grass in the spring. Researchers looked at ways to optimize the growth of these roots. After all, if you could get more root growth in the fall, than you would get many more new blades of grass in the spring. More blades of grass led to a thicker lawn that could actually force out newly emerging weeds. Experiments on how to maximize this root growth led to the following formula for the best root growth in the fall.
Before root growth could really begin in the fall, the grass needed to put up new blades of grass in the fall. This new growth helped to produce food to repair damage to roots caused by summer growing conditions. To achieve this, an application of a high nitrogen fertilizer in early September would give the nutrients necessary for new blades of grass. In about 6 weeks after the application of the high nitrogen fertilizer, an application of a fertilizer high in phosphorous and potassium allowed for the development of all of the new roots that would produce those new blades of grass in the spring.
This should be telling you that for a better lawn, now is the time to apply a high nitrogen fertilizer to your lawn. After you apply the fertilizer, you should water the lawn to release the fertilizer into the soil.
The roots of the lawn will take up lawn fertilizer as long as the soil is not too acidic. If there is a high amount of acidity in the soil, the fertilizer gets bound up in the soil and the roots cannot take up that fertilizer. To prevent this from happening, it is important to keep the Ph of the soil at about 6.5. In New England, this usually means applying lime each year to keep the Ph in that range. Fall is an ideal time to apply lime to your lawn. Lime does take time to work and by applying it in the fall, the Ph can change before that period of rapid growth in the spring. If you didn’t apply lime in the spring, or if you didn’t apply enough in the spring, now would be a good time to apply lime to your lawn.
Early September means the hatching of all of the eggs laid by the Japanese beetles. What emerge from those eggs are the grubs that eat the roots of your lawn. If you apply a grub control now, you will kill those grubs before they have time to do major damage to the roots of your lawn.
September is also a good month to start a new lawn or to repair any damage to an existing lawn. More about seeding your lawn next week.
Well, that’s all for this week. I’ll talk to you again next week.