Lawn renovation involves restoring an area of turfgrass to an improved condition. For lawn renovation to be successful, steps must be taken to correct underlying causes of turf deterioration. Common causes of turf deterioration include drought, excessive shade, weed infestation, disease, insects, poorly adapted grass species, soil compaction, poor drainage, excessive thatch, and inadequate fertility. I suggest targeting the second week of September through the first week of October for getting the seed down, I’ve found this to be the sweet spot in our area on past renovation projects.
The following suggested steps are best sequenced when thatch doesn’t exceed ½ inch and the existing population of desirable turfgrass is less than 50 percent.
- Soil test – Take a soil test three to four weeks in advance of renovation activities. Soil testing services are available from UMass Amherst Center for Agriculture Food and the Environment – https://ag.umass.edu/services/soil-plant-nutrient-testing-laboratory
- Weed control – By use of a nonselective herbicide to kill all vegetation in the lawn, or by use of a broadleaf herbicide which will selectively eradicate dandelion, knotweed, clover, etc. Be sure to follow the manufacturer’s recommendation concerning the required interval between herbicide application and seeding.
- Mow – Mow remaining vegetation to less than one-inch height and rake to remove all loose debris and excess thatch.
- Core Aeration – Use a mechanical aerating machine to remove plugs of soil from the turf area which alleviates soil compaction and prepares a partial seedbed. Initiate multiple passes over the renovation area with the core aerator machine.
- Lime – Apply pursuant to soil test
- Rake –Rake or drag (weighted chain link) the area to work lime into the soil and to break up cores from aerating.
- Seeding – Uniformly broadcast the seed over the area with a drop or rotary seeder. Alternatively, a slice seeder can be used. Choose a good quality seed adapted to your site’s unique conditions, i.e., solar exposure, available water, use conditions, etc.
- Fertilize – Apply a starter fertilizer pursuant to the manufacturer’s label.
- Roll – To initiate seed to soil contact.
- Mulch – Apply a light layer of straw to retain moisture and promote germination.
- Water – Keep the seeded area moist through germination and until the seedlings have become well established.
- Maintenance – From this point on utilize best management practices for pest management, proper mowing heights, watering, and monitor soil acidity.