THE BIO-INTENSIVE URBAN GARDENING SERIES – EPISODE 16

In episode 15, we explored the importance of Fertilization and Soil Testing which is critical to raising a profitable garden. If you missed the lesson read here.

For episode 16, we are discussing the chemistry of soil nutrients. To start with, soil is a major source of nutrients needed by plants for growth, elements present in the soil are the essential nutrients that plants need to blossom, hence the reason why this study is super important.

Soil Nutrients

Elements that are essential to higher plants are divided into 3;

1.     Primary macronutrients
2.     Secondary macronutrients
3.     Micro nutrients

Primary Macronutrients

They are Nitrogen (N), Phosphorous (P), and Potassium (K).

Secondary Macronutrients

They include Sulphur (S), Magnesium (Mg) and Calcium (Ca).

Micro Nutrients

They include Iron (Fe), Manganese (Mn), Zinc (Zn), Copper (Cu), Boron (B), Molybdenum (Mo), Chlorine (Cl), Nickel (Ni) and Cobalt (Co).

The primary macronutrients are needed in the soil in large quantities. That is one of the reasons we always see and hear about NPK fertilizers and that is what you see on most fertilizer packaging with a few putting the analysis of the secondary and micro elements on their products.

The secondary macronutrients are needed in small quantities while the micronutrients are needed in minute quantities for efficient plant growth. To determine nutrient deficiency in a garden or farm, it is most likely that there is a uniform occurrence across the field. It is very important for farmers or gardeners to be able to differentiate between nutrient deficiency symptoms and plant disease symptoms so as not to waste resources or lose investments.

Nitrogen which is a key element in protein serves as a fuel source for microorganisms in a compost pie and it helps green growth. Phosphorus gives energy to plants and it is important for the growth of flowers and seeds. Potassium helps in protein synthesis and the translocation of carbohydrates to build strong stems and roots which are the controlling part of a plant.

Sulphur, a constituent of ammonia acids in plant protein, is responsible for various flavours and odour components in plants. Magnesium promotes the sugar supply in growing fruits and it is a constituent of chlorophyll. Calcium strengthens cell wall structures while Boron promotes cell divisions, elongation and wall strength.

Magnesium plays a direct role in photosynthesis as part of the enzyme system and it helps to reduce the availability of phosphorus and calcium. Copper is essential in several plant enzymes as it is involved in photosynthesis and closely linked to Vitamin A production, so when your produce lacks vitamin A, know that you have issues with copper. Zinc is required for protein synthesis and growth regulation. Long internodes of large leaves are highly important at the early growth stage.

Molybdenum helps bacterial and soil organisms convert nitrogen in the air to soluble nitrogen compounds in the soil. This is essential for legumes and it is important for the formation of protein soluble nitrogen compounds. Chlorine is essential in photosynthesis where it is involved in the evolution of oxygen, increases cell osmotic pressure and water content of plant tissues.

Nickel helps to metabolise urea in nitrogen into usable ammonia within the plant. Without nickel, toxic levels of urea can build up within the tissue forming necrotic lesions on leaf tips. Iron regulates and promotes growth and it is a constituent of many compounds. Manganese helps with photosynthesis. Copper interacts with other elements to form complexes. It is essential for stem growth, elongating the coleoptiles and expanding the leaf tips. It is also a critical element for plants to reach maturity and for healthy broad development.