If you are not a seasoned plant whisperer, thats totally ok. Understanding more about what NPK is, will help you take a more educated approach to the use of fertilisers in your garden which will only enhance the health and vigour of your plants. After you have read this blog I encourage you to read my blog “Choosing the right fertilisers for your plants” which goes hand-in-hand with this blog.
Plants, just like us have dietary requirements. We need a varied amount of Carbs, Protein and Fats whilst plants need varied amounts of Nitrogen (N), Phosphorous (P) and Potassium (K) – each nutrient affects the plant in a different way.
Nitrogen: Encourages leafy plant growth and development, and encourages greener thicker leaves. Great for herbs, green leafy vegetables and thickening out of hedges.
Phosphorous: Encourages strong root growth, and the creation of flowers. Perfect if you want to encourage more spring flowering or maybe a second flush of flowers in the Autumn.
Potassium: Sometimes called potash, encourages the creating of flowers and fruit and increases plants resistance to pest and diseases.
So, NPK literally stands for the three major nutrients plants need. Now that you know how each nutrient affects plant growth you can begin to understand why you should choose a fertiliser base on your objectives in the garden.
now choose a fertiliser with a N-P-K ratio that suits your objectives in the garden, which is the best way to choose your fertilisers.
If a light bulb has gone off in your head than you maybe thinking “OMG! If I just put a whole heap of Nitrogen on to my lemon tree I am going to have THE biggest tree“. Well! before you go off and do this I should let you know that TOO much of a good thing can have dire affects on your plants. Excess nitrogen in the soil will be taken up by the roots and result in lush new growth, however the roots would not have grown to sustain that growth. After the nitrogen has been depleted from the soil, your lemon tree will start to go back ward – very quickly. And No! more nitrogen in quick succession from your previous heap is not the answer. ICE drug addicts don’t get more sexier and healthier the more they consume, neither will lemon trees if you you feed them excess Nitrogen.
You can purchase Nitrogen, Potassium and Phosphorus as separate nutrients and apply them as needed throughout the garden however unless you offer professional garden services, I would suggest you stick with the branded fertilisers that contain a varied N-P-K ratio at first. Choose your product based on what you might want to achieve in the garden.
Choosing the right fertiliser for your garden isn’t easy. If you have ever walked the fertiliser isle in your local garden centre you may have noticed a flood of products with fancy packaging, clever names and big claims. To say the least, I wouldn’t be surprised if your last fertiliser purchase was made in a flurry of confusion and settled for the one with the fanciest packaging – you wouldn’t first nor the last.
We all know that we can’t trust solely on packaging claims, I mean how many times have you bought a food item you thought was healthy only to check the nutrition label and find that its full of unhealthiness. Many people these days use nutrition labels to help them make better decisions about their health, if only fertilisers had the same label we could move past the fancy packages and get down to the merits of the product. Well the great news is that they do – its called N-P-K and is on every fertilising packet.