When we read about fertilising gardens, lawns or pot plants one of the most common piece of advice can be something like ”and use a fertiliser that is high in N:P:K” or ”use a fertiliser that has high in Nitrogen (N)”, that’s fine if you know what N:P:K is!
So what is N:P:K ?
Simply put, the N:P:K of a fertiliser is the measure of how much nutrient the fertiliser contains, the higher the N:P:K numbers the more of these nutrients it has. All plants need a balance of N:P:K and other elements to grow to their potential, a bit like we need a balanced diet to grow healthy and strong, so the N:P:K of a fertiliser is a very important part of your decision making when buying a fertiliser.
Government fertiliser regulations require all fertilisers to have their complete analysis on the pack, this includes the N: P:K of the product. This is usually found on the back of the bag or container and is called the analysis. At Richgro we make it easier for you by putting the N: P: K and S (Sulphur) on the front of the bag.
So to break it down what are N, P, K and S?
Let’s start with N. The N stands for Nitrogen. This element is very important for plant growth and is particularly important for plants that are green in colour as green plants tend to need more nitrogen. A good example of a green plant is lawn of any variety or lettuces, palms and ferns.
So in summary, N is great for rapid plant growth and particularly good for lawns and green leafed plants.
P stands for Phosphorus; Phosphorus is important in promoting root growth and promotes overall strength that helps plants survive through the colder winter months and extremes in temperature over summer months.
Most plants will benefit from the application of Phosphorus but be aware that Australian Native plants are Phosphorus sensitive so do not apply fertilisers with high phosphorus near these plant types. Specific fertilisers for Australian Native plants are available. Richgro Mega Booster for Native Plants for example, is specifically blended with low Phosphorus making it safe to use on these plant varieties.
K stands for Potassium; Potassium is essential to plant growth as it promotes bigger, healthier fruit and vegetables and in the case of flowering plants, more flowers and increased plant health. The most common form of potassium is Sulphate of Potash which can be bought in a soluble powder for liquid application or granular for spreading.
S stand for Sulphur; Sulphur is a much underrated element in plant growth it as important to plants as Phosphorus as it assists in the formation of plant proteins which in turn help with overall plant vitality.
So the next time you look at a bag to determine what you should buy, have a look at the analysis as this will assist you in that final decision. And remember that generally, the cheaper the fertiliser the lower the quality , when in doubt spend a bit more and you will get a far better result, happy gardening!
Colin Barlow shows you how to choose the right fertiliser for your Garden – http://https://www.youtube.com/watch?v=3xp6Vc0TxvI