Comment by krisroadruck

Avid backyard gardener here. When we moved to our new house in Fort Wayne our yard was a real problem child. It was a new build in an old neighborhood. All the other houses where about 40ish years old. Ours had also had a 40 year old house, but at some point that house was abandoned, eventually condemned and then knocked down. Eventually a builder snapped up the lot and built our current house. But that means the ground had been stripped of topsoil and compacted all to hell not once, but 3 times in the past 40 years. What was left was dead heavily compacted clay subsoil. It had drainage issues in wet weather, it developed crazy deep & wide cracks in dry weather, and just generally didn't want to grow anything.

We solved it by dumping around 400 cubic yards of arborist woodchips spread 12-18 inches thick over most of the yard, then top dressed that with composted manure and worm castings. Finally, we planted a bunch of wine cap mushroom spawn (to break down the wood) and clover (to fix nitrogen and feed the fungi) over the whole thing. 3 years later we have rich loamy soil that drains well, is full of earth worms and grows anything we plant it it.

TL;DR: Add tons of carbon and nitrogen into degraded soil and the local fungi, bacteria and worms will turn that into good soil if given sufficient time.