Choose a site that has lots of sunlight and good air circulation. Vegetable gardens should be located in wide-open sites for best results. The plants need lots of sunlight and not too much shade. If there are trees near your garden, make sure they're on the west or north side so they won't block the sun. Level ground is best as long as extra water can drain away from your plants.
A soil analysis will give you the pH level of the soil and the levels of nitrogen, phosphorus and potassium, as well as the levels of critical trace elements. Call your local extension service to get a soil test kit; they'll tell you where to send it and how to get the best samples for your soil type. You can also buy test kits at your garden center; the results are quick, but they're just not as accurate as what you'll get by sending a sample off to your county lab. The soil samples can go to your local extension service for testing. You get the results back in a few weeks.
To take a soil test you need samples from six to 10 areas in your garden; you need to get the soil below the surface to obtain the most accurate results. The soil directly on top may not give a true representation of what lies beneath, where the roots will actually be growing. To take a sample, dig about a trowelful of dirt and put it in a clean pot or bucket. Repeat this process in all areas of your garden; then pour the samples onto a cardboard lid or some type of wide pan and let the soil dry out.
Once you have all of the samples dried, put it in the bag provided by your county extension service (Image 1). The bags are designed to keep your sample from coming in contact with anything that might contaminate the soil. Seal it tightly so nothing falls out. Remember the goal of this test is to check the overall fertility and nutrient balance of the entire garden site. The lab will get more accurate results if the soil is ready for them to test (Image 2).