By which I mean "put down Miracle Gro soil."
Which means your basic soil mixture is pretty good, and you had a good location.
My Dad didn't use Miracle Gro, his secret ingredient was more bother to come up, but it did grow some killer tomatoes and other food plants as well. The ingredient was chicken shit, cleaned from his own chicken coops. Raising chickens, even prize show chickens, is at least as much bother as keeping plants from being pollinated.