By: Debra Stringer
Horticulturist

Healthy plants that grow properly and require little maintenance have one thing in common: good root systems.  Roots that can move through the soil freely help plants establish in new settings more quickly than those that are placed in compacted and poorly drained soils do.  Compacted soils force roots to either stay in the hole that you originally dug or grow very near the soil surface.  This situation greatly reduces drought resistance and increases the possibility of root rot from poor drainage.  It can also cause roots to eventually strangle themselves if they do not grow out of the original planting hole they were set in.  It is very similar to plant roots growing in a container.  Setting plants several inches above the surface and mounding the soil around them is not any better in the long run if the surrounding soil is compacted.  The roots will again follow the path of least resistance and grow along the soil surface.  The next time you see tree roots growing up through cracks in the pavement or sidewalks you will be able to see that the roots are growing where air is available.  Unfortunately this makes them more susceptible to mechanical damage and drought.  Raised beds are popular alternatives that are affective in situations where large tree roots are nearby or it’s just aesthetically pleasing to the eye to raise the grade in certain areas.  But remember, if you don’t improve the original soil under the raised bed, you will have drainage problems, and if you are creating raised areas for trees and shrubs, these plants will not anchor themselves deeply into the native soil that is now just a hardpan under the soil you till.  Just digging a hole in heavy clay soil and plopping a plant in, or piling soil on top of a hardpan for a raised bed is easier, but if you look at the big picture, a few years down the road, you will see that initial soil preparation will not only insure your investment in plant material, but enhance it.

So what do we do first?  Evaluate the soil.  A soil test is the best way to find out the nutrient values and needs of the proposed planting site.  Compressing a handful of soil can show the texture.  It should hold together yet crumble easily.  All the nutrients you apply will not be effective if they cannot move freely through the soil, latch on to clay-humus particles and have air and water available so they can be converted into forms that the root hairs can absorb.  The chemical reaction necessary for nutrient production and uptake requires the presence of negative charged particles like clay and humus.  It also requires water, air, and microorganisms.

A healthy soil is made up of 50% particulate matter (sand, clay, humus, organic matter), 25% pore space for air and 25% pore space for moisture.  This type of soil is easily found in natural forest areas that people don’t visit and there are tree canopies that protect the soil surface from the harsh sun and the rains that compact soil over time.  These areas are also protected from soil loss due to wind.  Roots that die from natural causes and tunneling mammals and insects help to aerate the soil in these natural areas.  In this undisturbed environment, organic matter (leaves, branches, insects, etc.) that die and decompose on the forest floor are able to break down into slimes that can flow down through the uncompacted soil, adhere to clay particles and form natural clots or aggregates in the soil that in turn create gaps for air and gas exchange, water movement, nutrient conversion, and root growth.  The perfect environment, but who has that in their backyard?

Many, many years ago, the first settlers didn’t use soil amendments like peat moss or pine bark.  Wood was used for heating and building structures.  In the crop fields, they would incorporate livestock manure and pea sized rocks and rock powders for nutrients and trace minerals.  The rocks helped create cracks in the soil for aeration.  Today we are gardening in soils that are not only compacted by man, machinery and nature, but quite often the topsoil has been stripped away completely to be replaced with who knows what or where it came from.  Many times it isn’t replaced at all.  When planting season arrives, we buy plants that are grown in specially blended growing mediums, take them home, and slap them in a soil that is initially foreign to them, low in organic matter, and very likely lacking in air and adequate drainage.  And we expect them to grow as if they were meant to be there.  The plants lack vigor, become diseased or even die from poor drainage, lack of water, or nutrient deficiency or overload.  We tend to blame ourselves or where we bought them.  What should be an enjoyable and satisfying project or experience becomes very frustrating.  It can also become expensive.  We buy more fertilizer, better fertilizer, and pesticides to control diseases and insects that are attracted to weak plants and poor soils.  As impossible and complicated as it seems, if we take a few steps in the right direction when preparing our planting sites and spend a little more time and energy balancing air, water, and particle spaces in our soil so that it is not only habitable, but inviting to beneficial microorganisms, then we can recreate the natural balance that plant roots thrive in.  Landscaping and gardening then becomes rewarding and satisfying.  Your investments flourish and you visit your local nursery or garden center with confidence and anticipation.

So how do we achieve healthy soils?  Sandy soils already have good drainage and aeration (unless it is the very fine sand particles) and need humus.  Soils that consist of tiny plate-like clay particles (ex. our southern clay) compact easily and lack pore spaces for air, water, and humus.  Clay particles hold moisture and further reduce the amount of available air pore space.  Breaking up clay soil to depths of 8 to 12 inches (depending on the plant to be installed) is the first and physically most taxing step.  The next step is adding amendments like ground up pine bark or compost.  The organic amendments are essential for healthy balanced soils, but they absorb water, and without adequate air and drainage can contribute to the growth of harmful fungi and bacteria.  The settlers used pea size gravel to improve aeration and some folks do that today.  The problem with gravel is that the particles are usually solid.  Roots can’t grow into and through the particles, and over time, the clay particles compact around the gravel, reducing pore space once more.  Gravel can leach minerals into the soil and affect nutrient balance.  Some people use Gypsum.  Gypsum is calcium sulfate, and in certain types of clay acts like a binding agent causing the clay particles to clot together or aggregate.  This chemical alteration of soil texture is temporary, and even though calcium and sulfur are essential nutrients, you don’t want to over do it.  Eventually these soils compact again due to man, machinery and nature.  The permanent solution for aerating soil is PermaTill.

PermaTill is a unique product produced from a special slate that is found in Gold Hill, NC where the first gold rush took place in the United States.  This particular slate is a half billion years old and has a different origin compared to other slates.  It is compressed volcanic ash formed by gradual earth changes due to volcano and glacier activity.  Typical volcanic or lava rock is made of large particles that make it brittle.  Volcanic ash particles are very small and dense in comparison.  The Carolina Stalite Company heats the slate in large kilns that maintain temperatures of 2000 degrees Fahrenheit.  At this temperature, the slate expands or bloats, whereas common slates would shatter.  The particles maintain their strength after the heating process even though they have become lighter and porous.  It is strong enough to use under pavement and sidewalks.  It has a low absorbency (6%); therefore it retains air and doesn’t absorb moisture away from plants like other amendments.  PermaTill is the superior aggregate for use in areas where trees are planted in pits surrounded by brick or pavement.  Roots will grow in the spaces and paths filled with PermaTill because the root hairs that absorb water, air and nutrients grow freely in and through the PermaTill particles.  It is also the number one medium used in roof gardens because it is light and it doesn’t break down.  It is used by itself for growing orchids.  PermaTill is permanent, offers superior drainage and aeration, and has a nutrient holding and exchanging ability that is higher than the clay particles in typical southern red clay.  Another application is water gardening; PermaTill is sterile and acts like a natural biological filter when used in water gardens.

The clay soils in our landscapes are difficult to work with.  You will probably discover a long and meaningful relationship with a 5-lb. mattock and a commercial grade spade fork.  But once you crack open the soil, add the right amount of PermaTill for 25% air space, incorporate composted organic matter for nutrients, and mix it together, the clay particles play an important role in moisture and nutrient retention.  Since PermaTill is permanent, you will only need to incorporate it one time.  Occasional additions of compost will move easily down through the soil wherever there is PermaTill.  How about that summer water bill?  When you water areas that have been prepared with PermaTill, you will see less runoff.  The soil surface is no longer impenetrable thanks to the porous particles.  Plant roots will grow deeply into PermaTill amended areas and be able to withstand drought conditions and help conserve water.  Roots that grow freely through soil that are balanced with particles, air, water and nutrients produce plants that are healthy and meet your expectations.  Now, that’s not so complicated, is it?

For more information, see our website: www.PermaTill.com or call 877-737-6284.