Why is it important to read fertilizer labels?
When growing plants, whether in an urban garden, a garden, or a hydroponic setup, understanding a fertilizer label is critical. These labels contain crucial information about the nutrients your plants will receive, helping you optimize their growth and health.
Essential elements on fertilizer labels
Primary macronutrients: NPK (Nitrogen, Phosphorus and Potassium)
Fertilizers list their composition with a three-number formula, such as 10-10-10, which represents the ratio of:
- Nitrogen (N): Promotes vegetative growth and foliage.
- Phosphorus (P): Essential for root development and flowering.
- Potassium (K): Strengthens plant resistance and improves fruit quality.
Secondary macronutrients: Calcium, Magnesium and Sulfur
These elements are also essential, although in smaller quantities:
- Calcium (Ca): Prevents structural and physiological problems.
- Magnesium (Mg): Key to photosynthesis.
- Sulfur (S): Essential for the synthesis of amino acids.
Essential micronutrients for growth
These elements, although in small quantities, are vital:
- Iron (Faith)
- Zinc (Zn)
- Manganese (Mn)
- Boron (B)
- Copper (Cu)
Interpreting numbers on fertilizer labels
What does the NPK ratio mean?
The numbers represent the percentage of each macronutrient. For example, a 20-10-10 fertilizer contains 20% Nitrogen, 10% Phosphorus, and 10% Potassium.
How to choose the right ratio according to the type of plant
Each type of crop has different needs:
| Type of Plant | Recommended NPK ratio |
|---|---|
| Leafy vegetables | High N (Ex. 20-10-10) |
| Fruit trees and flowers | High P and K (Ex. 10-20-20) |
| Grass | Balanced (Ex. 15-15-15) |
Types of fertilizers according to their composition
Organic fertilizers vs. synthetic fertilizers
Organic fertilizers come from natural sources, such as compost or manure, while synthetic fertilizers are manufactured chemically.
Liquid fertilizers vs. granular fertilizers
Liquids are fast-absorbing, ideal for hydroponic crops. Granules offer a gradual release.
Additional information on fertilizer labels
pH and its importance in nutrient absorption
The pH of the substrate affects the availability of nutrients. A soil that is too acidic or basic can prevent proper absorption.
Regulations and certifications in fertilizers
Quality seals and organic certifications
Look for labels like EU Organic or OMRI to ensure that fertilizers meet organic standards.
Common mistakes when interpreting fertilizer labels
Confusion with units of measurement
Some fertilizers list their content in grams per liter, while others list it in percentages. Make sure you interpret this information correctly.
Over-fertilization and its risks
Excess fertilizer can cause toxicity in plants and contamination of soil or water.
To find the best fertilizers and specialized advice, visit Hydroponics Blanes, your trusted Growshop.