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Don't Worry, it's Just a Name!
by John Harmon
April 27, 2003

There can be no doubt that spring is on its way in the Whitehorse area! The weather has been great and most of the snow is gone. One of the things that should be on your to-do list this spring is to test your garden soil. Testing your soil now gives you the advantage of knowing which materials you need to add to your soil so it will be perfect for spring planting. There are many choices of materials to add so the first thing you should do is test the structure of your soil.

Here's the simple way to test your soil structure at home. It has the fancy name of Soil Fractional Analysis but don't worry, it's just a name and it's not hard to do. You're going to need a good representative sample of your garden soil for the test. Start by taking a small soil sample every few yards throughout your garden. Small in this case means a handful. Take soil from the surface as well as down where the roots feed. You're going to till the garden later and mix up the surface soil with the soil deeper down so you want to collect a good representative mix.

Use some of the soil you collected and mixed for the Soil Fractional Analysis and save some for other tests. Take a quart canning jar or similar clear jar with a lid and put in a cup of dry soil. Add a teaspoon of non-sudsing dishwasher detergent. Fill the jar two thirds or so with clear clean water and put on the lid. Shake it up thoroughly till it's mixed completely. Set it aside someplace where it won't be disturbed for a few days till it's done settling. The soil will separate into its component parts. The top layer will be clay. Silt will settle in the middle and sand will go to the bottom. Now you have a visual idea of the structure of your soil. The target for good garden soil is 40 percent sand, 40 percent silt and 20 percent clay. By looking at the soil levels in the jar you can get a good idea of what you need to add to adjust the soils structure.

Take some of the rest of the mixed soil you collected and set it aside for soil testing. Once you have the structure right you want to check for content. Some of the garden centers here in Whitehorse do soil testing. Take a cupful or so of your soil in and they will test it. The test will tell you what the levels of Nitrogen, Phosphorus and Potash (NPK) are. These are the same numbers you find on the label of commercial fertilizers. If you want to test your own soil there are a number of soil test kits available. They are easy to use and give fair results but it's better to have it done by a garden center if you aren't knowledgeable about doing the testing. Once you know what the N, P and K numbers are you will be able to choose which fertilizer or other material you might need to use to get them right.

Another easy test you should perform is one that will tell you if your soil is alkaline. Put a tablespoon of dry garden soil in a cup and add a tablespoon of white vinegar. Mix it up and have a listen. If you hear a bunch of fizzing going on you will know your soil is alkaline. If you had your soil tested at a garden center they will also tell you if your soil is alkaline and can tell you what the options are to correct it.

Once you have the results of your soil test you will know exactly what kind of shape your soil is in and just what it needs. If you garden organically you will be able to choose the ingredients you use when making your compost so you add the right amendments to improve your soil. You can also mail off a sample to be tested. For a list of soil testing labs in Canada check out

A soil test will also tell you what the pH of the soil is. Beside lime there are many choices to adjust the pH of your soil. Compost will tend to lower the pH of alkaline soils and raise the pH of acid soils. Sawdust and peat are useful to lower the pH if your soil is too alkaline. Wood ashes, oyster shell, and bone meal are good for raising the pH of acid soils. The results of your soil tests will give you the information you need to tell which amendment you need and how much of it.

Once you have all your soil amendments and get them all tilled into your soil it won't hurt to do another soil test. The second soil test is worth the extra cost just to assure yourself that all the stuff you added was in the right proportions and balance just in case you have any doubts.

With a balanced soil you will have higher yields in your vegetable garden and better flowers in your beds. You will also have fewer problems with bugs and disease. Healthy, strong plants growing in good soil are just too busy getting big and producing to get sick or be bothered by bugs.

John Harmon owns and operates Tropicals North. Write to John at The Real Dirt, c\o 211 Wood St., Whitehorse, YT., Y1A 2E4 or e-mail


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