But Cooperative Extension horticulturist Amy Ivy has one chore you might want to cross off the list: "liming" the lawn. She talks with Martha Foley.
To lime or not to lime your lawn—that is the question. An application of powdered lime can sometimes raise the pH levels of your lawn and/or garden, so it can help with low pH problems. It is important to have your soil in the neutral pH range around 6.5 to 7.0. When the pH is in the right range the soil is much healthier and has more nutrients, which is better for growth.
Amy Ivy suggests doing a simple pH soil test first. It can be done at any extension offices and most garden centers. You don’t know what your soil is until you test it, she said, because there are many things you have added throughout the year that can change the reading.
About three-quarters of the pH tests that are done at Ivy’s extension office show too high a pH level, rather than too low. So in many cases there is no need for lime to be spread across lawns and gardens. The spreading of wood ash, which is about half as potent as lime at raising pH, can be used as an alternative treatment for low pH, but again, don’t use too much.
Lime that is sprinkled on the grass may be wasted, because it does not filter down into the soil’s root system where it is needed. Ivy joked, “Lime only moves when it’s on the lime truck coming to your farm.” More intensely managed lawns, such as golf courses, actually make holes in the lawn. If you were to do the same, and then put lime down, Ivy said, it would probably work its way down through the holes to the roots.
For the average homeowner, the lawn just needs to find its own balance, because there is not any easy way to change it. The only time when lime would really work is if you are starting all over, said Ivy, like fixing a dead area. Then it can be mixed into the soil and will help the grass establish quickly. After that the grass will find its own balance with the native soil.
Soil tends to be more acidic (low pH) in mountain areas where there is more granite bedrock and the soil is more sandy and gravely. Valley areas usually have more clay, which comes from limestone, and tends to have a higher pH. Soil with more clay is typically closer to the neutral pH reading. Ivy says there is no need to use winterizing fertilizer—research has shown it is too hard to time the application accurately.