Hi!

I'm in the middle of reading Square Foot Gardening and have a
question. In my backyard, I have an ideal spot to garden, however,
it's on top of cement. There use to be a small one-car garage there,
and the previous owner knocked it down but left the cement.

I was thinking of building a 4x4 box to garden in on top of the
cement. Will this work? How deep would I have to make it?

One of my concerns is about drainage. If I build it on top of the
cement, then the water probably won't drain well. I'm also concerned
about the hot/cold of the cement. I think dirt regulates heat/cold a
little better than cement. BTW, I also live in Chicago.

My other idea is to build it in the yard. I'd rather not do it
because the cement area gets the most sun, and my yard is pretty
small. However, if it will affect my yield, then I can spare some
room. ;-)

I would also like to plant (if it matters) broccoli, parsley, onions,
peppers, tomatoes, muskmelons, peas, carrots, beans (pole), and
corn....if possible.

Thanks in advanced for any suggestions!