DIY Hydroponic Fertilizer: complete guide for healthy plant growth

Hydroponic cultivation represents a revolutionary way of growing plants, allowing you to maximize yields in small spaces while maintaining precise control over nutrients. However, to achieve great results, you can either use commercial hydroponic nutrients or easily make your own diy hydroponic fertilizer. That’s why we’ve put together this complete guide on how to build a homemade hydroponic system and which cannabis fertilizers can be used for excellent results.

What is hydroponic fertilizer?

Hydroponic fertilizer is a nutrient solution formulated to provide all the essential elements plants need to grow in soilless systems.

Unlike conventional fertilizers, hydroponic formulas contain an exact ratio of macro- and micronutrients in a fully soluble form, allowing for direct absorption through roots suspended in water or inert mediums.

These fertilizers are designed to maintain the ideal pH and electrical conductivity (EC), two crucial factors in hydroponic systems that determine nutrient availability and uptake. A well-balanced hydroponic nutrient solution completely replaces soil as the nutrient provider, giving you unprecedented control over your plant’s feeding. You can easily grow with a complete hydroponic grow kit.

Why do your plants need hydroponic nutrients?

One of the main characteristics of a hydroponic system is that plants don’t have access to the natural nutrients found in soil, so they fully rely on the nutrient solution you provide. Supplying the right nutrients is crucial for several fundamental reasons:

1. Optimal development: Without proper nutrients, plants cannot complete their life cycle, affecting both vegetative growth and flowering.
2. Prevention of deficiencies: A balanced formula helps prevent nutrient deficiencies such as yellowing, necrosis, deformation, or stunted growth.
3. Yield maximization: A precise nutrient supply allows plants to reach their full genetic potential, resulting in better yield and quality.
4. Total control of cultivation: Hydroponics lets you adjust nutrition depending on growth stage, customizing the solution for either vegetative or flowering needs.
5. Efficient resource use: Hydroponic systems with accurate feeding use up to 90% less water than traditional farming and eliminate fertilizer waste.

Essential nutrients for hydroponics

Hydroponic systems require various essential nutrients for proper plant development. The necessary nutrients for hydroponics include:

Primary Macronutrients (N-P-K)

• Nitrogen (N): Vital for vegetative growth and protein synthesis.
• Phosphorus (P): Crucial for root development, flowering, and seed formation.
• Potassium (K): Enhances disease resistance and improves fruit quality.

Secondary Macronutrients

• Calcium (Ca): Strengthens cell walls and plays a role in cell division.
• Magnesium (Mg): Central component of chlorophyll and enzymatic activator.
• Sulfur (S): Involved in amino acid formation and protein synthesis.

Essential Micronutrients

• Iron (Fe): Aids chlorophyll synthesis and respiration processes.
• Manganese (Mn): Functions as an enzymatic activator in photosynthesis.
• Zinc (Zn): Regulates hormonal balance and protein synthesis.
• Boron (B): Involved in sugar transport and flower development.
• Copper (Cu): Supports photosynthesis and protein metabolism.
• Molybdenum (Mo): Essential for nitrogen metabolism.
• Chlorine (Cl): Aids photosynthesis and cellular osmotic balance.

Additional Beneficial Elements

• Silicon (Si): Strengthens plant structure and boosts stress resistance.
• Nickel (Ni): Involved in nitrogen and enzymatic metabolism.

Common Sources for Homemade Solutions

• Potassium nitrate (KNO₃)
• Calcium nitrate [Ca(NO₃)₂]
• Monopotassium phosphate (KH₂PO₄)
• Magnesium sulfate (MgSO₄) – Epsom salts
• Iron chelates (Fe-EDTA, Fe-DTPA)
• Micronutrient sulfates (ZnSO₄, MnSO₄, CuSO₄)
• Boric acid (H₃BO₃)
• Sodium molybdate (Na₂MoO₄)

Precise amounts of hydroponic nutrients

The exact formulation of homemade hydroponic nutrients depends on the growth stage and type of plant being grown. However, the following ratios serve as a general base for most plants in hydroponic systems:

It is essential to maintain the pH between 5.5 and 6.5 to ensure optimal nutrient availability, with an electrical conductivity (EC) between 1.2–1.8 mS/cm during the growth stage and 1.8–2.4 mS/cm during the flowering stage.

How to make homemade hydroponic fertilizer step by step

Making your own homemade hydroponic fertilizer allows you to customize the nutrient solution and reduce costs. To obtain a quality hydroponic nutrient mix simply, follow these steps to prepare a basic but effective solution:

1. Material preparation

Before starting the process, you need to gather the following materials:

• Mineral salts: magnesium sulfate (Epsom salts), potassium nitrate, monopotassium phosphate, calcium nitrate.
• Micronutrients: iron chelates, manganese sulfate, zinc sulfate, boric acid.
• Plastic containers for mixing.
• Precision scale (measuring in grams).
• pH and EC meter.
• Distilled or filtered water.

2. Preparation of stock solution A

To avoid issues, prepare two stock solutions (A and B) which will be mixed later:

• Dissolve 12 g of calcium nitrate in 1L of water.
• Do not mix with Solution B to avoid precipitation.

3. Preparation of stock solution B

Dissolve in 1L of water:

• 6 g of monopotassium phosphate
• 2.5 g of magnesium sulfate
• 8 g of potassium nitrate
• 1 g of commercial micronutrient mix or your own chelated blend

4. Preparation of the final solution

To make 10L of nutrient solution, add 50 ml of Solution A and then:

• Stir vigorously.
• Add 50 ml of Solution B.
• Adjust pH to 5.8–6.2 with citric acid (to lower) or baking soda (to raise).
• Check EC (should be between 1.2–2.2 mS/cm depending on the phase).

5. Application and maintenance

• Replace the solution every 7–14 days.
• Monitor pH and EC daily.
• Adjust according to the specific needs of your plants.

The best fertilizer for hydroponics

Although making homemade hydroponic fertilizer is a valid option, specialized commercial fertilizers offer precise and complete formulations that maximize results. Here are some of the best options available on the market:

Hydro-Supermix

Hydro-Supermix by Bio Nova is an all-in-one solution for hydroponic systems, noted for its versatility and balanced formula. This professional fertilizer contains all the essential macro and micronutrients in optimal ratios, supporting full development from germination to harvest.

Main features:

• Complete NPK formula + chelated micronutrients.
• Perfect balance for the entire growth cycle.
• Instant solubility with no residue.
• Compatible with specialized additives.
• Consistent results across various hydroponic systems.

Hesi Hydro Growth

The Hesi Hydro Growth fertilizer is specifically designed to boost the vegetative stage in hydroponic crops. Its formulation is rich in nitrogen and balanced with micronutrients to stimulate lush foliage and a robust structure.

Key benefits:

• High content of bioavailable nitrogen.
• Stimulates root development.
• Prevents deficiencies during the vegetative phase.
• Highly efficient concentrated formula.
• Optimized absorption technology.

Flower by Flower Power

Flower Power is the ultimate solution for the flowering stage in hydroponic crops. Its formulation is rich in phosphorus and potassium, with low nitrogen levels, and is scientifically designed to maximize flower and resin production.

Main benefits include:

• Significant increase in floral weight and density.
• Enhances natural aromas and flavors.
• Accelerates flowering metabolism.
• Compatible with recirculating systems.
• Enriched with natural biostimulants.

The strategic combination of hydroponic nutrients can make all the difference. That’s why crafting a homemade hydroponic fertilizer enhances nutrient input and results in high-quality crops.