Over-seeding means sowing grass seed over your existing lawn. A seed mixture that contains one or more modern varieties of Kentucky bluegrass, fine fescue and perennial ryegrass is recommended. Kentucky bluegrass provides a lush, dark green lawn. Fine fescue is a lighter green grass that blends well with bluegrass and tolerates shadier parts of your lawn. Perennial ryegrass is added because it germinates quickly and is more resistant to turfgrass diseases. Before overseeding, consider the following steps:
Preparing for Overseeding
1. Mow the lawn to about the height of 1.5"-2"
2. Rake up and bag the clippings
3. Aerate the lawn which reduces lawn thatch
4. Add a layer of topsoil especially if the topsoil is too thing such as areas with shallow tree roots. This is optional. However, majority of people do this anyway.
To properly overseed the lawn, use a spreader. This way the seeds will be evenly spread. The grass seeds need to be kept moist until germination. When watering don't allow the water to puddle or run off as this will wash your seeds away. It is recommended to use a fine spray to avoid a run off. This is a good time to apply a starter fertilizer. Once the grass blades sprout, water it a couple times per day. You can apply a quick-release nitrogen fertilizer after about five weeks.
The best time to overseed lawns in the Greater Toronto Area and Durham Region including Uxbridge is in early September or in the spring (April or May). Successful overseeding will allow you to cover patches in the lawn and have a healthy looking lawn for the summer.