We also have clay and I keep it covered with a straw mulch as well as adding as much humus as I can. The straw keeps the soil nice and damp and makes it workable. Where it dries out it sets like concrete. The straw gradually rots down and the worms pull it in to the ground. At the end of the season I dig in the straw and replace it for the winter which also helps the gound not to be panned by the winter rain.

After even one year of this treatment the difference is quite amazing.

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Gardening requires a lot of water - most of it in the form of perspiration. Lou Erickson, critic and poet