When starting late on amending soil, a lot can go wrong. Recently, I have come to the conclusion that sometimes it's ok to give up on the soil you're working with.
With three demanding small children I really didn't get to do that much to try to improve my nutrient barren backyard. I was led into this newbie move by being impatient, which isn't the best attribute for a gardener. I hoped that the soil wasn't as bad as I thought and just mixed in some rabbit manure into the ground and planted my seeds. Well ... in short I had mixed results. In one area where I had actually did some soil amendment the Kentucky Wonder Beans are growing strong. The other three beds have stunted growth or didn't grow at all. Which could partly be because of the weeds galore
So what DO you do when you through your hands up and curse the ground you plant on? Easy, you make a lasagna garden. No, not like the Italian dish but a layered soil where you can start fresh. In a lasagna garden you cover the soil with either cardboard or blank & white newspaper. This stuffs out the weeds and grass. I suggest you wet the paper down while covering the ground or placing rocks on top so it doesn't fly away with a gust of wind. Then alternate layers of organic matter (compost, manure, etc.) and coir, or a peat alternative (Top soil from garden centers work ok). And that's it! Then once your plants start sprouting spread a nice layer of mulch.
So if you feel like you are a horrible gardener, don't. Learn from your mistakes like I'm still learning now. Patience is the key to success in the gardening world.