Gardening from scratch

Here's what my back yard looked like last year:

It was a gravel parking lot. From satellite photos, it seems that the previous owner had had it that way for about 5 years.

In July, a landscaping company came and scraped the gravel off, put on some new topsoil, and seeded grass where we wanted grass. I've been planning a vegetable garden since then, and I knew the soil would be in pretty rough shape. It just has not had much going on for at least five years -- no organic material, nothing growing (aside from a few weeds), nothing.
Last summer, I put down newspapers and ordered a truckload of lake weeds that I piled on top of the newspapers to keep weeds from germinating before this year. I piled the weeds at least one foot thick all over my planned plot. It was a very unpleasant job, as the weeds include dead fish. Wheelbarrow after wheelbarrow of hot (they compost very fast and hot in as big a pile as they were in), slippery, stinky lake weeds. Here's what the soil looks like now. You can pretty clearly see the black, fibrous layer of last summer's lake weeds on top of the clay.

This spring, I've entered into an arrangement with a local coffee shop, and I pick up all their coffee grounds (with filters) each day. So every day, I dump out about 2 gallons of coffee grounds on a 2 foot square area and turn the soil over. It is heavy, solid clay, which comes out in one whole chunk. I break it up and mix it with the combination of last year's lake weed mulch (now about 1" thick) and the coffee grounds. I've also been working in whatever is most digested from my composter and a neighbor's chicken manure/wood shaving compost. I save the filters for a weed barrier in between rows, or I compost them. Here's what things are looking like so far this spring. We've got some grass coming up, though it could be thicker, and my vegetable garden, and lots of perennials that I planted late last year and forgot about: