Step 1: Have soil tested You can't look at the soil, or smell it, or feel it and tell whether it has 10 pounds or 100 pounds of available phosphorus per acre. But if you bring a sample of this soil to your local University Extension center, it can be tested to determine how much available phosphorus it contains.
Why is it so important to know how much phosphorus is in your soil? Because vegetables and flowers grow poorly where soils contain less than 100 pounds per acre.
Your soil test report also tells you the level of potassium, calcium (lime), and magnesium in your garden, and indicates the pH of the soil. In addition, it tells you the percent of organic matter, which is an indicator of the naturally available nitrogen that is released as the organic matter breaks down. This is about all you have to know to fertilize your garden soil properly.
To make it easy for you to interpret the soil test results, your report form will indicate which fertilizers, and how much, you should apply in carrying out Step 2.
How do you take a soil sample? 1. Take a spade and clean pail. 2. Push spade deep into soil. 3. Throw out a spade full of soil. 4. Cut a 1/2-inch to 1-inch slice of soil from the back of the hole with the spade. Be sure the slice goes 7 inches deep and is fairly even in width and thickness. Place this sample slice in the pail. 5. Repeat five or six times at different spots over your garden. 6. Thoroughly mix the six or seven slices you have in the pail. 7. After thoroughly mixing, take out about one pint of soil and mail it or, preferably, take it to your University Extension center or use one of our soil testing kits.
How long will it take to get the results? Use of our kit is immediate. Results usually take from one to two weeks, depending on the number of samples coming in to the soil testing lab. When should the sample be taken? Any time of the year - but if you can take your sample during October, November or December, you probably will get faster service than in the rush season, January through March.
How often should your soil be tested? Once every five years is sufficient if you follow Steps 3, 4, 5 and 6.
Is there a charge for this soil test? Yes, a nominal fee covers costs of chemicals and a technician.
Step 2: Establish basic fertility level This just means putting fertilizer - the right kind and right amount -Ñ on your garden. Your soil test report will indicate the kind and amount to apply. Remember that this basic application is a fertility-building process and will not be needed every year. After this level is established, it can be maintained by following Steps 3, 4 and 5. The best method for making the basic application is to put on half the recommended fertilizer and plow or spade deeply, then apply the other half and disc or rake in lightly. This distributes the fertilizer throughout the upper 7 inches.
Important: Your soil test report may recommend "no basic application." This means the fertility level of your garden is fine. If the report shows you have too much of an element, leave it out of fertilizer applications. Plowing just a little deeper for a year or two and sowing green manure crops also will help reduce the effects of those elements present at levels that are too high.
