Soil laboratory result


Sites are on the College of Micronesia-FSM campus.

pH Nitrogen Phosphorus Potassium
Red clay near administration 5.5 depleted depleted depleted
El Niņo fire burned soil across the road 4.5 depleted adequate deficient
Muck behind maintenance 7.0 depleted deficient deficient
Black soil from forest near agriculture building 7.0 depleted adequate deficient
Cyanobacteria Nostoc, ground up in a mortar - depleted depleted depleted
Coralline sand 7.5 depleted depleted depleted

Preparing your soil samples

For lawns, annuals or house plants, take the soil sample from about 2-3" below the surface. For perennials, especially shrubs, vegetables and fruit, the sample should be from 4" deep. 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 crumble the sample finely and mix it thoroughly.

Set a small amount of soil aside after cleaning (about a spoonful) for the pH test. The rest will go into the N, P, and K tests.

N, P & K Tests Only

1 . Fill a clean canning jar or coffee can with 1 cup of soil and 5 cups of water. (An aerosol can top also makes a handy measurement - use same 1 to 5 proportions.) For best results use bottled or distilled water.

2. Thoroughly shake or stir the soil and water together for at least one minute; then allow the mixture to stand undisturbed until it settles (30 minutes to 24 hours, dependent on soil). A fine clay soil will take much longer to settle out than a coarse sandy soil. The clarity of the solution will also vary. The clearer the better, however cloudiness will not affect the accuracy of the test.

When to test your soil

Testing your soil should be routine at the end of the growing season after harvest, again just before planting, and periodically during the growing season.

The importance of pH

Soils are known as "sweet" if they are alkaline and "sour" if they are acid. Values of pH 7 indicate a neutral soil; above pH 7 is alkaline and below pH 7 is an acid soil. Most Soils are within a range of highly acidic pH 4 to alkaline at pH 7.5 to 8.

If you wish to grow plants not suited to the pH of your soil, you can change the pH. You can make an acid soil more alkaline by adding lime. Slightly acid soils can be made more acid by adding peat, iron sulphate or flowers of sulfur. It is, however, more difficult to convert an alkaline, lime-rich soil into an acid soil.

pH affects the availability of plant foods - Nitrogen, Phosphorus and K (Potassium) - and prevents the spread of soil borne diseases. Check it regularly - at least twice a year - because nature tends towards the acid side.

Working with your soil - not against it - will help you achieve more successful results. Any changes in pH should be small scale - 1/2 to 1 pt at the maximum.

Adjusting pH

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 like the level revealed by your test.

Once you have your pH reading, check the enclosed pH Preference List for the pH levels of over 400 popular plants, trees, shrubs, vegetables and fruit.

If your pH test reading differs significantly from the list's recommended levels, follow the instructions below for adjusting soil pH by the addition of lime, iron sulfate, or flowers of sulfur.

Altering pH does take time so do not expect an immediate change. After adding lime or iron sulfate to your soil, retest for pH in 40 to 60 days - If results are still significantly off, retreat your soil , not exceeding recommended application levels.

When to add Lime

You can correct pH at any time of year but it is best (in temperate Northern hemisphere) to start in Fall and check progress in Spring. Allow one month to pass between adding lime and adding fertilizers.

How to make your soil more acid

To make soil more acid, dig in plenty of peat, compost and manure, and retest in a few months. For quick action use ammonia sulfate at the rate of 1 oz./sq. yd. or flowers of sulfur. But remember ammonia sulfate also adds Nitrogen (ammonia is NH3).

Recommendations for lawns

For a new lawn, pay special attention to soil preparation before planting. Proper soil preparation for any size will have a significant impact on the amount of water care it demands in the future. Till the soil to a depth least 12" and incorporate plenty of organic material more). Test your soil for pH and adjust to the levels following chart for your type of grass. Refer to the chart under "adjusting pH", for recommended lime sulfate applications.

Turf grass	   pH	    Turf grass	  pH
Bahia grass        6.5-7.5  St. Augustine 6.5-7.5
Bermuda Grass      6.0-7.0  Tall Fescue   6.0-7.0
Canada Bluegrass   5.5-6.5  Velvet Bent   5.0-6.0
Centipede grass    4.5-5.5  Zoysia        6.0-7.0
Kentucky Bluegrass 6.0-7.0

For established lawns, Nitrogen is the most essential nutrient to promote lush growth and deep, green color. Phosphorus and Potash, in lesser quantities, are all important for strong root formation and growth. Compound fertilizers will supply all 3 nutrients, or you select an individual fertilizer with a Nitrogen, such as our rapid feed Nitrogen with 44% Nitrogen.

Feeding your plants a "healthy" diet

There are three major plant foods which are essential to plant growth - Nitrogen, Phosphorus and Potash (potassium), expressed as N, P, and K.

NITROGEN (N) is essential to the proper functioning of plant metabolism. It increases the protein content of food crops and is needed by most leafy vegetables, foliage plants and grass. Nitrogen gives plants their dark green color (chlorophyll) and helps the growth of leaves and stems. Lawns, foliage plants and dahlias require a regular supply of nitrogen.

PHOSPHORUS (P) is the most important nutrient in root formation, creating good fibrous root systems. It enables plants to get off to an early start and hastens maturity. Phosphorus encourages blooming and seed formation, helps plants' resistance to wintry weather and disease and increases the vitamin content of plants. Lettuce, potatoes, carrots, for example, require good reserves of phosphorus.

POTASH (K) is probably one of the better known foods because it stimulates flowering and makes fruit tastier through converting sunshine into starches and sugars. Tomatoes, strawberries, beans, peas and flowering plants require especially high levels of potash.

Nutrient Replacement

Plant food deficiencies can be corrected by adding nutrients in the form of fertilizers. Nutrient replacement can be approached two ways: 1. Apply a general, slow-release fertilizer (usually organic) at the beginning of the growing season prior to planting. This creates a food bank for the plants to draw on and balances any deficiencies. 2. Feed established plants with the food they prefer, particularly in the case of vegetables, fruit and lawns. In all instances, feeding can be supplemented with a liquid feed (usually chemical) throughout the growing season.

Fertilizer Recommendations

Feeding: Soil Preparation

Adequate reserves of plant food should be available in the soil before planting vegetables, preparing a seed or flower bed, sodding or seeding a lawn, or planting shrubs and trees.

Feeding: Established Plants

Based on your test results, apply the appropriate fertilizers in the amounts recommends in the following chart:

Soil Test Kit Results

Depleted Deficient Adequate
N P K N P K N P K
Lawns 17 6 6 11 3 3 3 - -
Fruits 11 17 17 6 11 11 3 6 6
Flowers 11 17 17 6 11 11 3 6 6
Shrubs (flowering) 11 22 17 6 11 11 3 3 6
Shrubs (foliage) 17 28 11 11 14 6 3 6 3
Veg. (root) 11 32 11 6 16 6 3 8 3
Veg. (Leafy) 22 27 11 11 14 6 6 6 3
Trees 11 27 11 6 14 6 3 6 3
General Feeding 17 28 11 8 11 6 3 3 3

Amounts in chart are in oz./100 sq. ft. and are based an the following fertilizer sources:

N (N) - Ammonia Sulfate (21% N) Phosphorus - Super Phosphate (17.5% P205)

Potash (K) Potassium Sulfate (48% K2O)

Always water in when applying as top dressing on lawns or if rainfall has not occurred within 48 hours. If applied as a liquid feed do not water directly onto plants. Rest at least 10 days after adding fertilizer.

If you wish to use other fertilizers (e.g. organic), simply check the package for the percentage of nutrients for N, P, and K, and adjust the application level accordingly. For example if you have an 11 % Nitrogen fertilizer, then you would double the levels in the chart to achieve the same results.

Compound Fertilizers

A compound fertilizer is a mixture of all the essential foods a plant needs. Compounds are available in slow release (granular)and quick-acting (powder and liquid forms) and can be for general feeding or for specific plant

If you prefer to use a compound fertilizer, which should normally be applied during early Spring (slow release and during the growing season (quick-acting), use your soil test results to apply the fertilizer more efficiency You can thus avoid the possibility of over-feeding, which can be as detrimental as a lack of food.

If, for example, you find the levels for phosphorus and potash are both drastically low, you should increase the application rate of the compound by at least 100% and vice versa. Apply half of a soluble feed in dry form directly onto the soil and the other half as a liquid feed.

If, on the other hand, the levels are widely out of balance e.g. high in phosphorus and low in Potash you should not be using a compound fertilizer. This would not only be wasteful, but would increase the already high level to a potential excess.

Where a lot of fertilizer is needed to correct one p food, divide the applications over several weeks. Do not add lime and fertilizer together. Lime first. Allow least a month to pass before applying fertilizer.

The unique color comparison system

This new, easier-than-ever Rapidest( Soil Test Kit is designed for simplicity of use and accurate results. At the heart of the new system are 4 specially designed testing devices called "color comparators" - one each for pH, Nitrogen, Phosphorus and Potash. Each comparator has a removable film color chart and color coded top. Capsules for each test are also color-coded.

pH = Green

Phosphorus = Blue

Nitrogen = Mauve

Potash = Orange

A dropper is also provided to facilitate transferring the test solution into the color comparator.

pH Test Only

1 . Remove the cap from the green comparator and take out the package of capsules. Make sure the color chart (film) is in place.

2. Fill test chamber to soil fill line with soil sample.

3. Carefully separate the two halves of the green capsule and pour powder into the test chamber.

Note: To reduce powder spillage from capsules, hold the capsule vertically by the outside half (top) and gently tap inside halt (bottom) on a hard surface to settle powder. To remove top, hold capsule vertically at bottom with top pointing up. Grasp top and slowly twist and pull upwards until the two halves separate.

4. Using the dropper provided, add water (preferably distilled) to water fill line.

5. Fit the cap onto comparator, making sure it is seated properly and caps tightly. Shake thoroughly.

5. Allow soil to settle and color to develop for about a minute.

6. Compare color of solution against pH chart. For best results allow daylight (not direct sunlight) to illuminate the solution.

Refer to the information for adjusting soil pH, if required, as well as the pH preference List enclosed.

N, P & K Tests Only

1 . Fill a clean canning jar or coffee can with 1 cup of soil and 5 cups of water. (An aerosol can top also makes a handy measurement - use same 1 to 5 proportions.) For best results use bottled or distilled water.

2. Thoroughly shake or stir the soil and water together for at least one minute; then allow the mixture to stand undisturbed until it settles (30 minutes to 24 hours, dependent on soil). A fine clay soil will take much longer to settle out than a coarse sandy soil. The clarity of the solution will also vary. The clearer the better, however cloudiness will not affect the accuracy of the test.

3. Select the appropriate comparator for the test you wish to make. Remove the cap and take out the poly bag of capsules which should be the same color as the cap. Make sure the color chart (film) is in place and avoid interchanging color charts between comparators

4. Using the dropper provided, fill the test and reference chambers to the fill mark on the chart with solution from your soil sample. Avoid disturbing the sediment - transfer only liquid.

5. Remove one of the appropriate colored capsule from its poly bag. Carefully separate the two halves and pour the powder into the test chamber.

Note: Refer to pH Test step 3 for easy direction separating capsules without spillage.

6. Fit the cap on the comparator, making sure it is properly and caps tightly. Shake thoroughly.

7. Allow color to develop in the test chamber for 10 minutes.

8. Compare the color of the solution in the test chamber to the color chart. For best results, allow daylight (not direct sunlight) to illuminate the solution. Judge if necessary and note your results for future refer

Follow the same easy steps for each of the N, P and K tests. When you have the test results you need, refer the information above on fertilization guide lines.

Safety & Hygiene

Dispose of test solutions by rinsing down the sink. Empty gelatin capsules should be disposed of immediately with household waste. Remove the color charts. Wash the comparators and caps in soapy water immediately after each use. Make sure any sediment or color staining is removed. Rinse well and dry. Replace the color charts on the appropriate comparators. Each bag of capsule should be stored inside its comparator. Fit the caps on each and make sure the color charts are in place. Place all components back into the package. The blister pack has been specially designed to be reused as a storage container. Store your kit in clean, conditions indoors.

The powders are safe in normal domestic terms, but like all chemicals and pharmaceuticals, they should be put away and kept out of reach of children. Try to avoid touching the powders. Always wash your hands thoroughly after making your tests. Do not eat, drink or smoke while using the soil test kit. Keep powders away from food, drink and animal feed. If taken internally, drink copious amounts of water and seek medical advice.

This kit is available from:

Luster Leaf Products Inc.
2220 Tech Court
Woodstock IL 60098

For $15.95 plus $3.50 shipping and handling.

Fax: (815) 337-5567

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