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C-I-L® Soil Test Directions

How to Test Your Soil

Each test and capsule is colour coded: pH = Green, Nitrogen (N) = Purple, Phosphorus (P) = Blue, Potash (K) = Orange; with a separate colour bar to compare your results.

Before You Begin

Soil testing will not return accurate results until the soil is warm enough to support growth. Do not test in early spring until the grass has shown visible growth.

The soil pH level should be in the range 5 to 8 before testing the nutrient levels. A pH outside this range should be corrected. Allow 30 days after treatment for pH correction before testing nutrient levels.

Preparing Your Soil Samples

For annuals or houseplants, clear away surface soil and take the soil sample from about 5 - 8 cm (3-4") below the surface. For lawns, perennials especially shrubs, vegetables and fruit, the sample should be from 10 cm (4-6") deep. Use a clean shovel or spoon to avoid touching the soil with your hands. Test different areas of your soil, as it may differ according to past cultivation, underlying soil differences or a localized condition. It is preferable to make individual tests on several samples from different areas, than to mix the samples together. Place your soil sample into a clean container. Break the sample up with the trowel or spoon and allow it to dry out naturally. This is not essential, however it makes working with the sample easier. Remove any small stones, organic material such as grass, weeds or roots and hard particles of lime. Then using a spoon, crumble the sample finely and mix it thoroughly.

pH Testing

• Remove cap from one of the green-capped vials. Remove the green capsules.
• Fill vial with soil to the first line.
• Carefully open a green capsule and pour the powder into the vial.
• Add water (preferably distilled or bottled) to the fourth line.
• Cap vial and shake thoroughly.
• Allow soil to settle and colour to develop for about a minute.
• Compare colour of solution to the pH colour chart on the back of the box. For best results allow daylight (not direct sunlight) to illuminate the solution.
• Record your results and test location

Refer to the information that follows for adjusting soil pH, if required, as well as the plant pH preference list enclosed.

Soil pH - Results and Corrections

Soil acidity or alkalinity will affect the availability of nutrients to the plant. The pH can be adjusted to provide more suitable growing conditions for the different plants you wish to grow. Or, you can leave the pH of the soil as it is and select plants that suit the level revealed by your test. Once you have your pH reading, check the pH Preference List for the pH levels of popular plants, trees, shrubs, vegetables and fruits. Raising and lowering pH is not an exact science and most plants have a reasonably wide tolerance, certainly to within 1 pH point. The majority of plants can manage well on a pH around 6.5 but some need an alkaline soil (higher pH) and some a particularly acidic soil (lower pH). Altering pH takes time so do not expect rapid changes; rather, work steadily towards giving a plant its ideal conditions.

If your pH reading differs significantly from the list’s recommended levels, follow instructions below for adjusting soil pH. You can correct pH at any time of the year but it is best to start in the Fall and check progress in the Spring. Wait 30 days after a corrective treatment before retesting the soil. If results are still significantly off, treat your soil again, not exceeding recommended application levels.

N, P, & K Nutrient Test

Take a soil sample from about 10 cm (4") below the surface. Fill a clean jar or can with 1 part soil and 5 parts water (for best results use bottled or distilled water ) . Thoroughly shake or stir the soil and water together for at least one minute and then allow the mixture to settle out for at least 10 minutes.

• Remove the cap from the vial. Remove coloured capsules. (Please note that the colour of the capsules should match the colour of the vial cap.) Using the dropper provided, fill the vial to the fourth line with liquid from your soil mixture. Avoid disturbing the sediment.
• Carefully separate the two halves of one of the capsules previously removed from the tube. Pour the powder into the vial.
• Cap the vial and shake thoroughly. Allow colour to develop for 10 minutes.
• Compare colour of solution to the appropriate portion of the Plant Nutrients colour chart on the back of the box. For best results allow daylight, (not direct sunlight,) to illuminate the solution.
• Record your results and test location. Repeat for remaining capsules

Refer to the information that follows for adjusting soil nutrient levels, if required.

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