Answer: Whether you hire someone or do the work yourself, you should be familiar with good lawn care practices. The best time of year to renew or restore a lawn is early September so you have a little time to prepare. First you need to run some basic soil tests to check the fertility and pH levels. Amend these based on the test results. If you have to redo the entire lawn, you would fist kill out all the existing vegetation using an herbicide containing glyphosate. Read and carefully follow all of the label directions including any waiting periods. Then you would loosen the soil down about six inches and add organic matter to it along with fertilizer and lime as indicated by the soil testing. Then you would seed or lay sod. After planting, the area must be kept evenly moist while the new grass becomes established. In the fall, seasonal rains will help with this step. (In August, the weather tends to be hot and dry and is the most stressful time of year to be trying to start a new lawn.)
You could also try to restore your existing lawn through good care over a year's time and see how it does. Good care includes adjusting fertility and liming if necessary, mowing often at three inches, mowing often enough to never remove more than one third the grass height at a time, possibly a core aeration and topdressing with compost in the fall, as well as overseeding. This can help the lawn grow thick enough to crowd out weeds.
In general, any lawn care should be done consistently over the entire area such as the whole front or entire back yard at a time otherwise you will have patchy results. I should also mention that lawn grass needs full sun in order to grow well, so if your lawn is shaded you may want to consider using a shade tolerant ground cover instead of grass.
The following lawn care calendar should help you plan out what needs to be done.
In addition, your local Penn State county extension should be able to help you wiht the soil testing and interpreting the results as well as in planning what to do to improve or renew your lawn. Good luck with your project!
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