Soil is several things to a plant. It is the medium which holds the plant
upright. It is also the medium that holds the nutrients so that the plant
can gather them in order to grow, flower and fruit. Soil must also hold water
in suspension. So the plants can gather nutrients from it. There many substances
that, if modified slightly, might provide these three processes for a plant.
Cat litter will hold a plant upright and will suspend water quite well. If
the proper nutrients were added, cat litter would make an excellent medium
in which to grow plants. The problem is that there are many such nutrients,
elements and minerals. To provide them all, in very particular and sometimes
minute quantities would be a difficult task. Not impossible, but difficult.
Growing hydroponically uses such a process.
Certainly we dont have to start with some neutral medium. Right in your neighborhood,
or down at the local nursery, you can find soil that will fulfill the three
basic requirements to support plant life. Some are better than others, some
are easier than the others, but with some minor modifications, which will
be described in this chapter, most soils will support your cocal.
For beginners, it might be well to examine the three support systems that
the soil will provide for your plants: 1) supports the plant 2) holds and
provides nutrients, and 3) suspends water. In this way you can get a clearer
conception of how to provide the proper soil for your coca. You can be as
exacting as you wish, but there are certain basic minimum requirements.
1. SUPPORTING THE PLANT: Of course, the plant must be held upright in order
that it can function, but the matter is somewhat more complex than that.
It must be held gently but firmly. Firmly so that when it reaches six or
more feet in height, it does not fall over. Gently so that the plant has
room to move and expand to grow. The physical texture and structure of
the soil also plays a vital part in its ability to store nutrients and provide
them to the plants. Remember that the soil you choose must hold the young
plant gently but firmly.
2. HOLDING NUTRIENTS: Pedologists (soil scientists) have learned
that there are many nutrients that are important to plant growth
and more particular for our purposes, coca growth. The main
elements that must be in the soil for plant growth are nitrogen,
phosporous, potassium, magnesium, and sulphur. If the particular
soil you choose has a growth deficiency in any particular one
of these it can be made up with the addition of some special
substances. Sulphate of ammonia will provide nitrate and sulphate;
superphosphate, bone meal and basic slag will provide phosphate;
woodash and kainite will supply potash. Though these are a few
of the main constituents of those used in plant tissues, they
are by no means the only ones. Others which occur in minute
quantities, but which are just necessary for growth are known
as trace elements. This list of trace elements is constantly
being added to and increased until it may be soon shown that
all of the chemical elements - in however small an amount are
necessary - for really healthy plant growth. Although we only
need concern ourselves here with the main constituents of the
soil, it is well to note how complex the nutritive process is.
The three main nutrients, nitrogen, phosphorus and potash are
those contained in fertilizers. The three numbers on fertilizer
bags are the indices of how much of each is contained in the
fertilizer. The first number gives the amount of nitrogen, the
second number the amount of phosphorus and the third number
the amount of potash. The Sudbury Soil Testing Kit, which is
available at nurseries, uses color charts to help the cultivator
determine the percentage of each plant food that is needed in
the fertilizer mixture when it is applied at the rate of 5 lbs.
per square feet. The kits are easy to use and a must for a serious
coca cultivator. The soil tests may show, for an example, that
the fertilizer should contain 10% N, 20% P and 12% K. A fertilizer
analyzing 10-20-12 would be ideal. Of course, fertilizer analyzed
at 5-10-6 would work equally as well, but the amount added would
have to be doubled. Caution should be exercised whenever fertilizer
is added. Fertilizer is easily overdone and over fertilizing
will burn your plants up. It would be a good idea for every
grower to touch a bit of fertilizer to his tongue and see how
it stings. It would give him a much better picture of why fertilizer
must be applied with caution.
3. HOLDING WATER: The size of grain of which the soil is composed is of considerable
importance to plants because this affects its water-holding capacity. Between
the grains of soil there are gaps through which the water will travel. If
the gaps are big, water will pass down very easily, but it will not pass
up. It is only in soil where the gaps are small, as in clay or loam, that
water will travel up as long as there is surface evaporation and enough water
to keep supplying the surface. This process is called capillarity. Much less
water is lost by evaporation when the surface of the soil is kept loose.
In close conjunction with water, it is important to remember that the roots
will need air as well. Therefore, it must not be concluded that plants need
wet soil. Almost the opposite is true. If the soil were so wet and waterlogged
that air couldn't penetrate, the roots would be unable to breathe and the
plant would die. It follows then, that the texture of soil must be such that
it can hold some water between its granules, yet be loose enough to allow
the water to drain and the plant roots to breathe.
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