50% compost and 50% soil

[Dean Hiller]

We live in colorado and are going to dig out 6" of the top dirt/clay and replace with a 50/50 mixture of compost and soil(I am still researching which compost but am looking at some of the stuff on richlawn.com). My question is since I am digging out 6" which is really the deepest I think a bluegrass mix of grass will go, do I even need to both tilling the soil/compost into that top area of clay (ie. the 7th and 8th inch of clay below the surface). I mean, it may seem better to actually let the water stick there anyways rather than wasting it to leak below the 6" mark....right? or am I wrong and may end up with it pooling too much water therefore preventing the roots from wanting to be 6" deep.

thoughts? Should I till it in or should I just replace all 6 inches. I had a neighbor go past the typical 4" that most people do and it just looks way better and way easier to take care of going the full 6" (and it lasts many more years after the fact too).

thanks,
Dean

 

[Vinaya]

I make compost in a compost pit as well as compost bin. It takes just about three months to decompose organic waste in a compost pit and just about one month on compost bin. My compost pit is 3 by 5 meters and I use the compost on my farm land. I make compost in a bin for the backyard gardening or pot gardening.

 

[Corzhens]

Isn't that 50-50 mixture of soil and compost too much fertilizer? May I suggest that you put the 50-50 mix be in the bottom part of the 6" topsoil maybe the bottom 3 inches and the upper 3 inches would be 90% soil and 10% compost. Take note that compost as fertilizer is also hot and it needs more irrigation and too much compost may harm the plants.

 

[Sheal]

Welcome Dean.

If you are gardening on clay then I'd be inclined to remove that top six inches and then dig over at least a further six inches below. At the same time digging in some sand or small gravel to help open the soil up and give drainage. If you don't you will probably find you have minor flooding during heavy rain fall that in turn will rot the roots of your new lawn. 50/50 topsoil and compost can then be laid on top or dug in, but remember that compost is organic and will eventually rot down. Roots of most lawn grasses will only need 4 inches of soil to grow but the lawn will be healthier with more.