Answer: For either vegetables or flower beds, clay soil is usually best amended with ample amounts of organic matter (such as compost, milled sphagnum peat moss, rotted leaves, spoiled straw or aged stable manure and bedding or any similar material) and a small amount of sand. You should also run some basic soil tests to see what additional amendments are needed during this initial soil preparation phase. If your soil is very heavy clay you might want to use raised beds. To do this, loosen the soil and add the amendments, then add additional soil from your own property to achieve the needed height. A height of anywhere from a few inches to about a foot can be helpful in improving drainage and encourraging better plant growth. Your county extension (971-0079) should be able to help you with the soil tests and interpreting the results.
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