Garden Insurance with PH Soil Testing

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Soil Testing pH Meter

Her Majesty the Rose, Queen of all flowers, adored the world over by millions. Her beauty, fragrance and language of love has been the theme of those gifted words makes my poor effort to praise seem presumptuous.

As I am not a rose “expert” (not even a rose “fan”) I shall not discuss rose care. My love of roses is limited to a humble dirt gardener’s admiration of growing beautiful things.

However, like most gardeners, I do have a “first love,” mine being our soil, the medium which feeds, clothes and shelters us while giving the beautiful flowers so well loved.

Soil is “just dirt” only when tracked indoors or found behind the ears of healthy offspring. In the garden soil is a living, dynamic thing capable of being improved or misused to the point of ruination.

The respect and understanding which we exercise in the use of it predicates the prosperity of our future; indeed, predicates whether or not we have a “future.”

In spite of today’s advancement in rocketry and space-travel, compact cars and vitamin pills, we are just as dependent on Mother Earth as when friendly Indians taught our Pilgrim Fathers to bury a dead fish under each hill of corn.

Soil Make Up

  • Soil consists of many things:
  • Rock fragments of varying sizes
  • Plant and animal remains in all stages of disintegration which eventually form humus; of living organisms
  • Bacteria
  • Molds
  • Yeasts and
  • Fungi

… all playing a part in the formation of humus and its conversion into usable plant nutrients, soil solutions and gaseous elements.

It is my sincere hope to bring to you a simple understanding of soil and to convince you of the vital importance of soil testing. Ideal rose soil (ideal garden soil for that matter), is of a granular consistency called a “crumb structure.”

This porosity encourages deep rooting and allows air to enter the soil freely. Air is essential to soil organisms and to healthy roots.

A crumb structure holds moisture like a sponge, affording ample supplies of usable plant nutrients while accomplishing fast drainage of excessive moisture and leaching of adverse salts which would become toxic if retained.

This structure can be obtained in practically any soil with proper supplementation. You’ll find literally thousands of books and pamphlets printed and distributed expounding rose culture in great detail.

Those of recent vintage refer repeatedly to soil pH. The glaring shortcoming of this information, in my opinion, is that no writer ever seems to encourage the gardener to make his own soil test.

They inform readers that an Agricultural College, the local Department of Agriculture office or by a reputable commercial laboratory can perform soil testing.

The few articles which actually deal with testing are based upon laboratory-type operations involving chemical symbols, intricate logarithmic equations and couched in such terminology as:

  • Ionization
  • Ionic exchange ratios
  • Densities
  • Electrolysis

… and such innumerable other technicalities as to require either intensive study or a college degree for understanding.

Hob by gardeners will of necessity discard such information in disgust and label soil-testing as “something for the scientist.”

Locking Up Plant Foods – Acid or Alkaline

Over-acidity or over-alkalinity causes plant foods to “lock up,” that is to unite with other chemicals into insoluble compounds that plant roots cannot absorb. It will also destroy or seriously slacken the activity of soil organisms. The resulting yellowing (we call it chlorosis) of leaves, defoliation, bud blasting and drop – sometimes death – spurs us to frantic, “guess work” methods of correction.

Let me ask you a question. Would you men drive your automobile into “Jiffy Lube” and order a quart or two of oil without first checking to see if oil were needed? Of course not!

Would you ladies add salt or seasonings to your recipe without first tasting to see what’s needed – and how much? Of course not!

Yet you, kind sir, and you, dear lady, will go into your garden and pour “everything in the book” on your rose beds and landscape plants without the faintest idea in the world what is needed, or how much. Why? Because you saw it on TV?

Because your favorite garden magazine had an article by a rose expert who recommended it? Because your favorite nurseryman told you it was a good product?

Those sources were probably dead right – it may have been the best product on the market BUT not one of those people knew the condition of your soil. Consequently not one was actually qualified to tell you what that, or any other product, could do for you.

Another beautifully stupid trick we’ve all been guilty of at one time or another is to “double up” on recommended quantities on the assumption that if a little is good, a lot is better.

For heaven’s sake, don’t add things until you know they’re needed, and then stick to the manufacturers recommendations. He spends millions on research to provide those specifications.

Let’s not get involved with chemical formulas. Few of us want, or need, to delve that deeply. For now, we’ll settle on our old friend H20 (water).

In the soil a tiny portion of the water (about one part in ten million) ionizes and the chemical structure (H20) breaks down into an ionic structure H – OH). A few of the H – ions reunite with certain elements, but most of them escape into the atmosphere as pure hydrogen gas.

The OH – ions (called hydroxyl ions) are considerably more receptive to compounding and unite quite readily. A preponderance of hydrogen ions in the soil creates acidity – hydroxyl ions cause alkalinity.

Mathematical Notation Called pH

In testing soil, a mathematical notation called pH has been established to indicate the relative acid-alkaline condition present. The term pH is based upon water ionization and means “potential Hydrogen.”

The expression is in common usage because the relative degree of acidity is so vitally important and can be so much more briefly and precisely stated in figures than in words.

The figure 7 has been established as the middle of the scale or true neutral point. Readings below 7 are increasingly acid as the number decreases; readings above 7 are increasingly alkaline as the number increases.

Plant food manufacturers are required by law to indicate on each package the percentage of the three primary nutrients; nitrogen, phosphorus (phosphate) and potassium (pot- ash) contained in the formula, in that order.

Thus, a 5-10-5 formula tells us we are purchasing 5% nitrogen, 10% phosphate and 5% potash. Other elements (called trace elements) are not tabulated.

They are present in satisfactory quantities in most average soils and are to be found in minute amounts, intentionally or otherwise, in most commercial fertilizers.

Let’s digress a moment and look at the elemental breakdown of a rose plant. It is about 75 percent water which is taken up by the roots from the soil.

Water serves in a dual role, acting as the transportation system that carries nutrients in solution from the soil and for moving from place to place within the plant the elaborate food materials manufactured by it.

The remaining 25 percent is solid (or dry) material, 50 percent of this dry material is carbon dioxide.

Carbon, in combination with water is recombined by the chlorophyll with the aid of sunlight into starches and sugars, a process we call photosynthesis. Such use of hydrogen ions in water frees oxygen ions which the plant releases in gaseous form into the atmosphere.

Forty percent of the dry matter is made up of hydrogen and oxygen in various compounds other than water.

The remaining 10 percent of the plant contains nitrogen, phosphorus, potassium calcium, sulfur, iron and magnesium in varying proportions together with very minute amounts of manganese, boron, copper and zinc.

These are all obtained in solution from the soil and although they represent only a small part of the total weight of the plant they are indispensable.

Soil Elements are Lost in Many Ways

Soil elements are lost in many ways. Cutting flowers and foliage to take indoors, raking and removing leaves, pruning, weeding, leaching and wind-blown topsoil all contribute to the loss. These must be replaced at the right time and in the right quantities if our roses and other landscape material are to flourish.

Thus you can see good healthy plants are the result of good soil-husbandry, and good soil-husbandry simply cannot be without a soil test to determine the correct proportions of replacement elements.

Testing assumes even greater importance when you consider these elements though necessary become toxic in over supply.

A rose plant is just as dead from poisoning by too much food as by starvation. Believe me, you can’t correctly balance food sup- plies by estimates, crystal ball or your neighbor’s requirements. A soil test is the only accurate “balance sheet.”

The most favorable pH range for roses is 5.5 to 6.5 (slightly acid). Within this range the bacteria that fix atmospheric nitrogen and the fungi that change nitrogen compounds in organic matter perform best. Also, the organisms that convert ammonia to nitrates (the usable form of nitrogen for plants) do best in this range.

The relative availability of all elements except phosphorus is excellent too at the 5.5 to 6.5 range. Phosphorus avail- ability tapers off quite sharply at 6.0 which is an indication that perhaps it would be best to maintain pH as nearly 6.0 or 6.5 as is practical.

At any rate, it isn’t too critical a problem if you drop to 5.5 – a bit of inexpensive superphosphate will carry over nicely until the pH has been “cranked up” a little.

I may as well add also that our good crumb structure is easiest maintained within this same range and our great good friends, the earthworms, seem most plentiful and active too.

If tests indicate that your soil is too acid the addition of limestone or wood ashes (never coal ashes) will correct the condition nicely.

High acid soil is also generally a bit shy in calcium and magnesium, so a little gypsum (calcium sulfate) and Epsom salts (magnesium sulfate) might be added at the same time – remember to add these sparingly as an over supply is toxic.

High alkalinity is a bit more complex to handle as it is so often associated with poor drainage which must first be corrected. With good drainage, natural or attained, alkalinity can easily be regulated with additions of soil sulfur as indicated in the following table:

Sulfur in pounds

pH value per 100 sq. feet

  • 7.5 1 pound
  • 8.0 2 pounds
  • 8.5 3 pounds
  • 9.0 4 pounds

Iron sulfate may also be used at the rate of one or two tablespoons per plant (dry) or as a liquid at two pounds per 10 gallons of water for each 100 square feet. NEVER use aluminum sulfate on roses – aluminum is deadly for them.

Slight alkalinity caused primarily by hard water can be effectively controlled with periodic long, deep watering that will leach away much of the adverse salt accumulations. Salt build up happens in potted plant especially.

I realize many of us love to stand each evening after work and sprinkle things by hand. It’s relaxing, gives a person a chance to meditate, but DON’T do it.

When your roses need a drink, set a sprinkler or soaker (or fill the basin if your beds are set up that way) and allow the water to run long enough to soak down at least six inches.

Don’t water again until the surface is quite dry, in most areas about ten days to two weeks. This encourages deep rooting, a prime requirement for long blooming and survival in hot weather.

Now, let’s recapitulate. We’ve learned roses, to do their very best, must have a proper balance of food elements, good soil structure and pH and a carefully regulated supply of moisture. We’ve also learned testing is the key to this accomplishment.

So, just as Mr. BestPlants Grower checks his oil before adding more, and Mrs. BestPlants Grower tastes her cooking before adding salt or seasonings, we must run a test of our soil before adding anything. It’s most essential to know how much of what is needed.

I will never forget the “soil testing” learned from my father. It was simple, direct, and thoroughly inaccurate.

You simply picked up a pinch of soil and put it in your mouth. If it tasted sour, it was acid and needed lime; if bitter, it was alkaline and needed sulfur. When neither sour nor bitter it was “‘sweet” (neutral) and ready for planting.

But oddly enough, we often got the poorest crops from the “sweetest” tasting soil, which was always blamed to a “bad year.”

Now, there are modern laboratories everywhere with elaborate equipment and up-to-the-minute techniques that can tell everything about your soil. This is a “must” for the commercial grower who must cut costs and boost production in order to remain in business. This is not true of the “hobby gardener.”

There are several home-garden soil test kits available at better garden supply centers and nurseries. They are offered in several sizes, from a “midget” that tests for pH only to a real “super-duper” that does everything but kiss the kids goodbye. These are inexpensive, simple to use and above all safe.

Run Test Every Three Months

Tests should be run at least every three. months (quarterly), perhaps a bit oftener after taking severe correctional steps with particularly bad soils. You will discover that variations occur from bed to bed and from season to season.

Nature provides a constant change in the chemical and organic makeup of all soils, and man with his fancy ideas and superstitions aids materially in upsetting the applecart.

There is no need to clutter up this article with detailed instructions for conducting a soil test. Each kit contains clear, concise instructions together with everything needed in the way of equipment.

All tests are simple and can be conducted on the back porch, in the garage or right out in the yard whichever you elect.

Some soil test kits have even converted the numerical scale to a color scale so that you need only make a color comparison to have your answer quickly and safely. You work out no mathematical equations and you need no knowledge of chemistry.

From a “money angle” the kits cost no more than a good sprinkler or spray gun and will last a lifetime. Replacement solution costs are so little, as to be negligible.

Timewise, complete tests in a huge garden can be made in a couple of hours, probably less once you’ve acquired the simple routines. That adds up to only about eight hours a year of your valuable time.

When you discover how much less plant food, soil supplements and water you’ve used as a result of testing, you will realize the soil testing kit has paid its way and given you back some change and you’ve enjoyed the “biggest, bestest, bloomingest” roses and plants in the neighborhood.

All of us prefer living under safe, assured conditions. We spend huge sums annually for instance; on our homes, our automobiles, our liabilities and our lives. Your soil test kit can well be considered “successful garden insurance.”

Certainly there’s no better way to be sure of success with landscape plants and roses and you don’t have to have an accident, or die, to cash in on it. And besides, scientifically grown roses are always “far and away better than guess work roses.”

Contributed by F.R. Laughton