Saturday, March 5, 2011

"NPK- The big three" FAQs

1)    What is NPK? All plants, any species in the world, needs 4 major elements for its survival, growth and reproduction -Nitrogen (N), Phosphorous (P) and Potassium (K) and Carbon (C). The first 3 are coined as NPK available as chemical fertilizer and carbon is generally available from organic manures.

2)    Great, where do I get it? Your plant will get these normally from soil and manures. However, they need to be broken down into forms that can be absorbed so the plants can use them. Our invisible friends such as bacteria and visible wriggly friends such as earthworms do this. Think twice before you chuck out the hardworking critters.

3) What does Nitrogen do?
  • Nitrogen is a part of all living cells and is a necessary part of all proteins, enzymes and metabolic processes involved in the synthesis and transfer of energy.
  • Nitrogen is a part of chlorophyll, the green pigment of the plant that is responsible for photosynthesis. 
  • Helps plants with rapid growth, increasing seed and fruit production and improving the quality of leaf and forage crops. 

4)    What does Phosphorus do?

  • Like nitrogen, phosphorus (P) is an essential part of the process of photosynthesis. 
  • Involved in the formation of all oils, sugars, starches, etc.
  • Helps with the transformation of solar energy into chemical energy; proper plant maturation; withstanding stress.
  • Effects rapid growth.
  • Encourages blooming and root growth.

5)    Why Potassium?
  • Plants absorb potassium in larger amounts than any other mineral element except nitrogen and, in some cases, calcium. 
  • Helps in the building of protein, photosynthesis, fruit quality and reduction of diseases.

6)    So do I need to add a chemical fertilizer containing NPK to my soil?
Yes and no.  Often a cause of debate (chemical fertilizer production causes pollution and harms the environment in some cases) NPK formulations have been used since as far back as 1800’s. Farmers and commercial growers swear by it, because these fertilizers are fast acting and absorbed by the plant very quickly. They also need to be used in smaller quantities for same result as organic manure- because they are concentrated.

7)    Are chemical fertilizers more expensive? Of course! But you do get more bang for your buck…

8)    Are they all I need? No. Fertilizers containing NPK, contain just that. They are the basic plant food, but not the complete set of nutrition. Plants still need micronutrients, other macro elements like Carbon, Sulphur, Calcium, and Magnesium etc.

9)    So should I stick to organic manure? Sure. But if you have very old pots with soil in them, or you have moved into a newly built plot with no garden, just bare empty soil in your backyard, the soil will need to be replenished. Use a combination of NPK, which will give a quick boost of nutrients to your plant along with organic/farmyard manures or compost, which will release smaller amounts of nutrition over longer period of time.

10) Have you got a drip irrigation system? Water-soluble NPK formulations will work great with your drip system and because they are absorbed quickly, and dispersed more accurately than flooding the bed.


  1. Hi. You have a very interesting blog, with a lot of useful information on it. I'm glad to have found it, and am looking forward to keeping up to date.
    Best regards,

  2. Hello. I found your blog on Excellent article on NPK. I love all the people, like you, growing organically. I do my best to use what I can to grow organically.

    Keep up the great writing.


  3. Hi Simon and Spencer,
    Welcome to the Greenbay blog. Since you both are very successfully growing your own veg's, please do stay in touch with us and share your experiences.