Removing clay soil and replacing soil for new sod

Question

I’ve been struggling for a while trying to save my 12x12 front yard grass from not growing well and dying. Mostly because the clay soil doesn’t absorb any water from the rain and it just becomes puddly/muddy. It can rain on a Sunday and then be 70°F for a week and still muddy after a week of no rain and good sunny weather. The grass has died off in patches and way past trying to have it survive or do any kind of patch fixing.

I’m going to remove all the grass this weekend and replace at least 8inches depth of the clay with better soil that can drain better and the grass can grow better on. Here is my question can I use all topsoil to fill this area to have the best soil or would there be a better mix. After filling up the soil I will lay new sod back down.

Answer 1

Drainage is a touchy one. It might be that just the eight inches is enough. Or you could just wind up with eight inches of wet soil on top of the clay.

I would suggest digging down a foot or two in one small location to see how much clay you have. If the clay is deep you may still have problems after replacing the top layer. If you want to encourage draining, you might need to get yourself some sand to mix in with the soil. The usual "best practice" sand is called "play sand." It should be available from the same garden store you got your topsoil. This is sand that has been washed in a river or lake to wear off the sharp edges on the grains. It then is pleasant to walk on, and good for your grass. No more than 50% sand is the usual rule.

If it's possible to arrange to have a small slope in the grass that would probably be very helpful. Even a slope of one or two inches over your small patch of lawn would be very helpful. Slope it away from your house or you could wind up with a wet basement. If the possible "down hill" place is a good place to have water drain to, then that's a good plan.