posted 6 years ago
If that dirt has been under concrete for 20 years it most likely is also contaminated since construction workers rarely are concerned about keeping spills from occurring while they are laying forms and installing rebar or wire mesh.
You want to think a bit about a good plan of attack, this will allow you to take less time and end up with a really good start up soil.
As Walt mentioned, manure and compost are naturals and most people do start with these, but there are other things to consider prior to spreading these microbe containing goodies.
This dirt might be contaminated, fungi are great cleaners of contamination, especially when they are able to work with the bacteria and other organisms of the microbiome.
Fungi need lignin in the soil, which is the material already broken down in good compost and well rotted manures.
That means you might want to see about first adding straw or cleaned hay or if you don't worry about "weeds" sprouting in-cleaned hay works well. This gives a cheep, usually easy to find batch of organic matter that has a lot of fungi food built in.
Most of the organisms you want can be grown by heaping up lots of different materials that can be gathered as people start cleaning up their lawns in the spring, these material are usually set at the curb in big black bags (leaves, twigs, first growth clippings, etc.)
all work for growing the soil biota you want and a bit of spoiled milk, past good to eat fruits and vegetables, everything but meats can be added to the heap, including a bag of rotted manure and or compost.
If you go to my soil threads, I have posted a lot of information on building soil not only quickly but also rich in life forms, and I am usually around some 5 days a week so if you have questions, just ask them, I'll answer and others will too.
Redhawk
Once you have the dirt turning into soil you might want to think about long term fungi food like wood chips for a soil top dressing/mulch layer.
2
