Choosing the right NPK fertilizer for your garden can be a tricky task if you don't know the needs of your plants. NPK fertilizers contain nitrogen (N), phosphorus (P) and potassium (K), the three essential nutrients for healthy plant growth. Depending on the type of plant and its stage of development, the proportion of these elements varies, so it is important to know which is the best combination.
We are going to tell you the Differences between NPK fertilizers, how to interpret their proportions and which one is the most suitable depending on the type of crop. We will also see whether it is preferable to opt for liquid or solid fertilizers and how to apply them correctly to obtain the best results.
What is an NPK fertilizer and what is it used for?
An NPK fertilizer is composed of three fundamental macronutrients that plants need for their growth:
- Nitrogen (N): Essential for the development of leaves and stems, promoting vigorous growth and an intense green color.
- Phosphorus (P): Essential for root development, flowering and fruiting.
- Potassium (K): It helps the plant's resistance against diseases, improves the quality of the fruits and regulates the transport of water in plant tissues.
The proportion of these elements in fertilizers varies depending on the type of plant and its development phase. For example, a 20-20-20 fertilizer has balanced amounts of N, P and K, while a 10-10-30 has a higher potassium content, ideal for plants in the flowering stage.
How to interpret the proportions of an NPK fertilizer
Fertilizer labels show three numbers separated by dashes, such as 10-10-10 or 12-24-12. These indicate the percentage of each macronutrient in the mixture:
- The first number represents the nitrogen (NOT).
- The second number indicates the match (P).
- The third number corresponds to the potassium (K).
Depending on the type of plant and the time of its growth cycle, one formula may be more suitable than another. For example:
- For young plants or newly sown grass: A high phosphorus fertilizer, such as a 12-24-12, is recommended to encourage strong root growth.
- For green leafy plants: A fertilizer with more nitrogen, such as a 20-5-5, encourages lush leaf production.
- For flowering and fruiting: A 10-20-20 helps to promote flowering and the production of healthy fruit.
Liquid vs. Solid Fertilizers: Which is Better?
NPK fertilizers are available in both liquid and solid forms, each with its own advantages:
- Solid fertilizers: They are usually found in granule or powder form. They are ideal for soil applications and have a slower release, providing nutrients over time.
- liquid fertilizers: They are absorbed more quickly, so they are useful in fertigation or foliar application. They allow immediate nutrition, but require more frequent applications.
The choice between solid or liquid will depend on the type of crop and the application method you prefer.
How to apply NPK fertilizer correctly
For the fertilizer to be effective without harming the plants, it is recommended to apply according to these criteria:
- Do not exceed the recommended dose: Too much fertilizer can burn plant roots.
- Ensure uniform distribution: Spread the fertilizer well around the plants to avoid excessive concentrations in one spot.
- Water after application: This helps nutrients penetrate the soil and be absorbed by the roots.
If you use liquid fertilizers, add them to the irrigation water according to the manufacturer's instructions. If you want to know more about how to prepare homemade fertilizers that benefit your plants, check out our guide on effective homemade fertilizers.
Which fertilizer to choose according to the type of plant?
To make it easier to choose the best fertilizer, we leave you some recommendations according to the type of crop:
- Grass: A high nitrogen fertilizer, such as a 15-5-10, to encourage a denser green canopy.
- Vegetables: A balanced 10-10-10 fertilizer or with a higher phosphorus content if they are in the flowering stage.
- Fruit trees: Preferably with a higher amount of potassium, such as 10-5-20, to enhance the formation and quality of the fruits.
It is essential to know the specific needs of your plants when you choose the right fertilizer.
Using the right fertilizer and applying it properly will make your garden look more beautiful. healthy and with optimal growth.
