Answer: Clay soil can grow a terrific garden. The main concerns are that it does not drain well and then once dry, can be difficult to remoisten. It also will compact and harden like concrete if worked when it is overly wet. This means that there may only be limited windows of opportunity when it can be worked. If it sticks to your shovel, it is too wet. If it is too hard to dig into, it is too dry. Generally speaking I would suggest adding generous amounts of organic matter such as good quality compost, rotted leaves, well aged stable manure and bedding, spoiled straw, or similar materials. Loosen the soil and work in the organic matter; a layer six inches thick is not too much. You may also want to add some coarse sand (builders' sand, not the fine play sand) or some fine grit, maybe an inch. Gardening on a slight slope or using a slightly raised bed can also help. Then take care to add organic matter on an ongoing basis by using an organic mulch year round, this will help feed the soil as it breaks down over time. Your soil improvement program will be a long term one. In addition to the above, I would recommend you work with your county extension to run some soil tests and determine if any particular amendments such as lime or fertilizer may be needed, depending on what plants you wish to grow. They may also have information on soil preparation under local conditions and on plant selection that would be helpful to you. Finally, you will want to select plants that tolerate a clay based or heavier soil, so definitely avoid those that need perfect drainage or a sandy soil. I hope this helps you get started.
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