Lawn Topdressing & Overseeding (Simple Guide)

When to do it

In Ontario, the best time to topdress is early spring—usually March through early May. You want the grass just starting to grow, while the weather is still cool.

When to start

Don’t rush it. Wait until the ground is firm and dry. If it’s still soft and soggy, you can do more harm than good by compacting the soil or leaving ruts. Once the lawn starts to green up and you’ve done a good spring rake and cleanup, you’re ready to go.

What soil to use

The goal is to match or improve the soil you already have. We use a 50/50 mix of ultra-fine organic compost and sand.

The compost adds nutrients and healthy microorganisms that help your lawn (and even your gardens) thrive. The sand helps with drainage—especially important in the GTA where a lot of soil is heavy clay.

Step 1 – Cut it short

Mow your lawn down to about 1–2 inches and bag the clippings. You want the soil to actually reach the ground, not sit on top of loose grass.

Step 2 – Aerate (if you can)

If you’re able to core aerate first, do it. It puts small holes in the lawn so the soil, water, and nutrients can get right down to the roots.

Step 3 – Add the soil

Spread your topdressing soil in small piles around the lawn, then work it out evenly.

You’re only going about ¼ to ½ inch thick—don’t bury the grass. You should still see the blades sticking through.

Step 4 – Level it out

Use the back of a rake or a levelling rake to work the soil down into the grass and fill in any low spots. This is what helps smooth the lawn out.

Step 5 – Seed and feed

Now’s the perfect time to overseed. Use a good mix like perennial ryegrass and Kentucky bluegrass that works well here in Ontario.

You can throw down a starter fertilizer too if the lawn is actively growing—it’ll help it come in faster.

Step 6 – Water

Give it a light watering right after you’re done. After that, keep it damp with light watering every day until the new grass comes in.

We supply quality soil, seed, and materials—and we deliver. We also offer full service and free estimates if you want it done right the first time!