Answer: A little, but not much. Certainly wouldn't hurt. However, your best bet would be to till in some organic matter such as compost, leaf mould, or composted cow manure...and lots of it! This stuff is great for breaking up clay soil. In addition to loosening the soil, it provides nutrients for your plant life. If you do this every season at tilling time you will, in time, have soil to make any gardener green with envy.
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