Section 5: Plant Growth Requirements

Glossary

Lesson 6: Nutrient Requirements


Plants need certain minerals and nutrients to grow and survive. Most of these nutrients are supplied by the soil, and are dissolved in water and taken up by the plant through its roots.

The three primary macro-nutrients, so called because they are the most important nutrients needed by plants in large quantities, are often added to the soil by means of commercial fertilizers or manure and compost. These three important nutrients are:

Nitrogen is needed for above-ground growth; it's what gives plants a dark green colour.
Phosphorous helps plant cell division; it aids in flower and seed production and also in the development of a strong root system.
Potassium helps fight off disease; it also provides for strong stem growth.

    There are also three secondary macro-nutrients needed by plants in fairly large quantity.
    These are:  
     

    • calcium

    • magnesium

    • sulphur



      Although these secondary macro-nutrients are needed in fairly large quantity, they rarely need to be added to soil artificially, since they are generally readily available.
      However, in western Canada, there is a trend to add some sulphur to the content of commercial fertilizer preparations.

      A pile of compost consists of organic matter that has been decomposed. It can be recycled as a rich fertilizer and soil conditioner. Almost any organic matter can be composted.
      Source: http://www.cyber-north.com/gardening/compost.html 

      ©iStock
       
      ©iStock
       
      Plants also need other micro-nutrients, so called because they are needed in very small amounts.
      These are also generally available from soil. They are often referred to as trace minerals and consist of the following: iron, manganese, boron, chlorine, zinc, copper, molybdenum, nickel, selenium, and sodium.
      Fertilizer with a high nitrogen content will result in the intensive green of a lawn.
      But the other primary macro-nutrients must also be present.
      The same is true of all grass-like crops, e.g., cereal crops such as wheat, rye, and barley.

        Digging Deeper


      Plant Requirements   

      Click here to view a video on "How to Grow a Forest in Your Back Yard".  Many of the concepts discussed in this section, are also addressed in the video.