How to tell if you have clay
Squeeze a handful of damp soil. If it holds together in a smooth, sticky lump and you can roll it into a ribbon, it's mostly clay. Water that sits for hours after rain is another sign.
Why clay is tricky
Clay drains slowly, so water sits after rain. It compacts easily under foot traffic and machines. It swells when wet, shrinks and cracks in a dry summer, and heaves with frost in winter.
Get the grade right first
On a flat Windsor lot with clay underneath, water has to be sent somewhere. The ground should slope away from the house so rain runs off instead of soaking in by the foundation. Grading comes before any lawn, bed or patio.
Lawns on clay
Sod does well on clay with the right prep: the old lawn out, the ground levelled and sloped, and a layer of good topsoil on top where the existing soil is poor. Then water deeply and less often once the sod has rooted, so the roots grow down.
Garden beds on clay
Plants struggle in heavy, waterlogged clay. Bringing in fresh soil, and raising beds slightly above the lawn, gives the roots something to grow in and helps water drain away.
Plants that cope with clay
Some plants handle heavy soil better than others. Daylilies, coneflowers, black-eyed Susans, switchgrass, ninebark and red osier dogwood are all good places to start. Whatever you plant, give it fresh soil around the roots, and don't let it sit in standing water.
Turf, patios and driveways
Anything hard or synthetic needs a compacted granular base between it and the clay. That base spreads the load, lets water move and keeps the surface flat through freeze and thaw.
Don't work it wet
Digging or rolling clay while it's soaked turns it into a dense, airless layer. Clay is best worked when it's moist but crumbly, not sticky.
Don't just add sand
Mixing a little sand into clay doesn't loosen it, and it can set even harder. Bringing in fresh soil, and working compost into beds over time, does more good.
Is gypsum worth it?
Gypsum is often sold as a clay fix, but it rarely does much unless the soil has a salt problem. Fresh soil and compost do more.
Clay and your foundation
Clay swells when it's wet and shrinks when it's dry, so the soil along your foundation moves through the year. Keep the ground sloped away from the house, and top up any low spots that form beside the foundation so water doesn't collect there.
When water still won't leave
Grading moves surface water away from the house. If water is coming in through the foundation or up through the basement floor, that's a job for a waterproofing contractor.
Working with clay in your yard?
Free on-site estimate anywhere in Windsor-Essex, with a written quote the same day. One-year warranty, fully insured and WSIB covered. Call or text 519-567-4724.
