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Plant growth
Eating locally grown organic food is important for your health and the health of
the
planet. You can’t get more local than growing this nutritious food yourself.
What could be better than good food and light to medium intensity exercise in
the fresh air?
Lets start by understanding the plant life cycle shown above.
Sand, silt and clay in various ratios are the
main ingredients of soil. They are inert but can contain many plant required
minerals in plant unavailable forms (water insoluble).
Healthy soils are teaming with microbes:
bacteria, fungi, and other forms of biological life such as insects and
earthworms. They live by digesting organic matter from dead plants and plant
root exudates. It is a complex interconnected ecosystem often referred to as the
soil food web.
As well as soil and the soil food web, plants
need the following to grow:
Energy from the sun for photosynthesis.
This is the main mechanism for converting energy to matter. It pays the
bills.
Air-Carbon dioxide for plants to grow structure.
-Oxygen to keep the soil aerated for micro-organism
metabolism. Without air soil can go anaerobic. If this happens
soils start to pro duce alcohols which are toxic to plant roots.
-Nitrogen which can be captured by nodules in some plants’
roots
Appropriate temperatures
Water for nutrient exchange
Major nutrients such as nitrogen, phosphorus, potassium. Minor nutrients
such as calcium and magnesium. Trace minerals
All of this is fairly well understood. Less well
understood is what happens when plants die and decay. The soil Micro Organisms
(MO) begin digesting Organic Matter (OM) from dead plant materials.
Understanding the MOOM interaction is key for the organic gardener.
The final products of organic matter decay are humus and carbon dioxide. In the
soil carbon dioxide joins with water to form weak organic acids which have the
ability to react with the storehouse of mineral nutrients in plant unavailable
form (remember them from our discussion of basic soil) and make them plant
available (water soluble). At the same time humus has the unique ability
to hold electro-statically, the now plant available nutrients until required by
the plant. Humus is a very important transitional material. It is the product of
death and decay but it also contains within it the material for new life, the
hub of the wheel of life. An enlightened society would find ways to protect
humus and produce more. Will the current Alberni-Clayoquot Regional District
waste management review be enlightened enough to recommend composting
biodegradable wastes which make up 25% of the waste stream? It would be
important for the health of the planet and the health of the community to do
this.
The next columns will examine MO & OM in more detail and how organic gardeners
can assist the MOOM interaction.
The plant life cycle graphic was provided by the Alberni Environmental
Coalition.
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Sustainable
Living Through Organic Gardening