testing machine for npk value from a test tube in a lab for plant nutrients

What is NPK value in plant nutrients?

The NPK value indicates how much nitrogen, phosphorus and potassium there is in your substrate or fertiliser. These three essential macronutrients are needed by all plants. Knowing the NPK value of your soil and fertiliser helps you give the right amount of nutrients to your plants.

What is the full meaning of NPK?

Nitrogen, phosphorus and potassium. Let’s review what each of these three nutrients does for your plant.
  • N stands for nitrogen. Nitrogen is needed for the growth of a plant.
  • P stands for phosphorus. Phosphorus promotes the formation of roots and development of flowers and fruits.
  • K stands for potassium. Potassium helps move water and nutrients around in your plants.

NPK explained in plant fertiliser

Let’s take a closer look at the value itself. For example, the NPK value of Alga Bloom is 3-2-5. This means it contains 3% nitrogen (N), 2% phosphorus (P) and 5% potassium (K).

How to use NPK fertilisers for plants?

A plant does not need the same amount of these nutrients in each phase. This is why substrates and (liquid) fertilisers do not all contain the same amount of NPK. Some products, like our non-fertilised substrates, don’t contain NPK at all. This way, you can decide yourself how you want to get nutrients to your plants.

It’s important that your plant receives enough NPK and other nutrients. If it does not, it may start showing deficiency systems. You can read more about nitrogen, phosphorus or potassium deficiency in our grow topics on the subject.

Do you need help during your grow? Contact our Grow Expert via Servicedesk.
young seedlings in fresh soil enjoying the sun
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