Hydroponic Nutrients Guide: What You Need for a Successful Grow


Grow Generation Editorial 

With hydroponics, you can grow almost anything indoors without soil. However, one of the most critical aspects of hydroponic growing is properly providing the nutrients your plants need to thrive. Keep reading our hydroponic nutrients guide to learn more about plant nutrition and the different types of hydroponic nutrients and related products that growers should understand. 

What are hydroponic nutrients?

Hydroponic nutrients are a type of plant food specifically formulated for use in hydroponic (soilless) growing. They are vital for your plants to thrive indoors because — unlike traditionally grown plants — those produced hydroponically don’t have soil to help provide and deliver nutrients.

Hydroponic growers must take an additional step and provide all the essential nutrients that plants can’t grow without, including the big three: Nitrogen (N), Phosphorus (P), and Potassium (K).

To be considered hydroponic nutrients, formulas must meet three basic requirements:

  1. They must be 100% water soluble.
  2. They must be 100% mineral salt form (not organic).
  3. They must include all 14 of the 16 essential elements—except carbon and oxygen, which plants get from the air.

Below is our hydroponic nutrients guide to understanding the differences between soil and hydroponic plant nutrition.

Plant Nutrition in Soil vs. Hydroponics

To help you better understand hydroponic nutrients, it helps first to know how plant nutrition typically works in soil-grown plants.

Plant Nutrition in Soil

In traditional growing, nutrients come from minerals in rocks, soil, and decaying organic matter, such as leaves and branches. To be used by plants, organic materials must decompose into inorganic matter. Gradually, nutrients are released into the soil, where plant roots absorb them.

In addition, soil organisms such as bacteria and fungi help to release nutrients that would otherwise be locked up in the soil. Once absorbed by the roots, nutrients are transported throughout the plant, where they are used for various functions like cell growth and photosynthesis. Growers regularly supplement their soil with organic matter like compost and manure to replenish nutrients.

Plant Nutrition in Hydroponics

In hydroponics, plants grow in watertight containers with their roots nestled in a growing medium, such as perlite, clay pebbles, coco coir, or peat moss. Growing media supports the plant’s root system, which handles nutrient absorption. Those roots are directly exposed to the nutrient solution (water mixed with hydroponic nutrients). As a result, the plants can take up nutrients more quickly, allowing them to grow faster and achieve higher yields.

Plants primarily only uptake essential nutrients in their non-organic, mineral-dissolved salt form—regardless of whether the source is organic or synthetic. Hydroponic nutrients are in their inorganic ionic form, ready-made for uptake and use. This structure gives hydroponic growers a shortcut that bypasses the lengthy and complex processes needed to break down organic nutrients (via mechanical and/or microbiological pathways naturally occurring in soil).

Next, we will guide you through the different macronutrients, and micronutrients plants need and the vital functions they make possible. 

16 Essential Macronutrients & Micronutrients for Plants

Plants require 16 essential elements to grow. Each of these elements is considered either a macro- or micronutrient. The difference between macronutrients and micronutrients lies in how much element plants require. Plants need macronutrients in higher amounts than micronutrients. 

From structural differences to their roles, let’s go over each element and explain its importance. 


Plants that require high levels of nutrients are macronutrients. Below is a list of macronutrient types and the functions used for hydroponics success. 


Nitrogen nutrients increase yield production and food quality in hydroponics. It encourages protein growth, which in return, increases the leaf area of a plant. 


This macronutrient plays a role in the beginning stages of plant growth. Phosphorus is responsible for maturing the seed for solid blooms and roots. 


When it comes to potassium in hydroponics, this nutrient acts as an immune system booster for plants. Potassium strengthens the plant to prevent disease, helps crop production, and increases quality control. Nitrogen, phosphorus, and potassium are the top three macronutrients in most commercial fertilizers.  


This mineral helps plant metabolism, which is critical for hydroponic plant development. Sulfur assists with building proteins, amino acids, and vitamins for adequate growth and maturity. 


Magnesium produces chlorophyll which affects plants during photosynthesis. The signs of magnesium-deficient plants include discoloration and growth delays. 


This macronutrient is responsible for cell growth and root division. Calcium helps cycle water movement and contributes to plant growth and disease prevention. 


Adding a small amount of hydrogen peroxide into nutrient solutions is like treating wounds. It kills bacteria and stimulates new growth as it would for your skin. Hydrogen assists with water purification to help fight root rot and algae buildup since it is constantly moist. 


Plant photosynthesis is the mirrored version of how we breathe — they breathe in carbon dioxide (CO2) and exhale oxygen. It is one of the essential nutrients for hydroponic systems. 


Oxygen is a macronutrient essential in hydroponics because it generates air bubbles in the water. The bubbles help aerate the water and oxygenate the plant roots needed for growth and development. It also plays a part with CO2 in photosynthesis.


Nutrients that plants need only small amounts of are called micronutrients. Let’s discuss some of the different micronutrients essential for your plants to grow.  


The effects of iron in plants are similar in how it impacts the human body. Iron is a micronutrient that works in hand with chlorophyll production. It cycles oxygen throughout the plant structure, which gives plants their healthy green color. 


Zinc also assists with the production of chlorophyll, enzymes, sugar, and protein. This mineral is responsible for the vegetative and blooming phases of the plant cycle. 


When it comes to boron, it acts as a vehicle because it transports sugars throughout the plant structure. This micronutrient supports reproductive growth, plant functionality, and stability. 


This micronutrient is responsible for seed development. It also helps chlorophyll production by interacting with the enzymes necessary for yield growth. 


This element acts like hot steam before applying a facial cleanser product. It opens the pores to take in solutions easier. Chlorine opens plant pores to take in the nutrients needed for growth. A sign of healthy chlorine levels in hydroponic gardening is strong leaves. 


Manganese is an essential nutrient for activating enzymes during chlorophyll production. This element helps plants absorb light and energy, which are the fundamentals of gardening. 


This mineral is one of the hydroponic nutrients responsible for regulating plant functionality. Molybdenum ensures nitrogen converts into ammonia which is essential during the growing process. Some signs that your plants have a molybdenum deficiency include discoloration and stunted growth. 

Now that you know the importance of all the essential nutrients you need to provide for your plants, it’s time to pick out your products. In the next section, we will guide you through some of the most common types of nutrient products that growers need to understand. 

Different Types of Hydroponic Nutrients

When shopping for hydro nutrients for the first time, you’ll notice a few different types of nutrient products. Let’s go over the differences between various nutrient products on the market for hydroponic growing.   

Hydroponic Base Nutrients

Hydroponic base nutrients provide a mixture of all the different essential nutrients plants need. Like the kibble you feed your dog daily, base nutrient products offer a complete, nutritious diet for your plants in just one formula. There are different base nutrients for various plants, and even for the individual stages of plant development, for example, separate grow and bloom formulas. 

Grow vs. Bloom Nutrients

The difference between grow and bloom nutrients are the stages of the plant life they impact. Grow nutrient solutions assist during germination to seed production. Bloom nutrients help during the flowering stages to support plant maturity. 

NPK Ratio

The NPK ratio is the amount of a fertilizer’s nitrogen (N), phosphorus (P), and potassium (K). As mentioned above, these three macronutrients are the top three ingredients found in commercial hydroponic base nutrients. These three numbers are the percentage of these elements’ solutions. 

Understanding the NPK ratio is key to helping growers find the right type of nutrient products. A general base with a balanced NPK ratio, for example, 5-5-5, would be a nutrient formula with 5% nitrogen, 5% phosphorus, and 5% potassium. 

Different formulas with more significant amounts of certain nutrients boost different parts of the plant at different growth stages. For example, the NPK ratio for bloom phase nutrients will have a higher percentage of phosphorous to help with seed maturation for solid blooms and roots. 

Organic Base Nutrients

Another choice is whether you want to invest in organic nutrients over synthetic ones. Organic options are made from plant and animal byproducts that are a good source of certain nutrients. For example, some organic nutrients are made from bone meal (which is high in phosphorous and fish emulsion, which is a good nitrogen source. 

Organic solutions are generally a higher quality option, just like in the vegetable aisle. Growth and taste are impacted by what you feed to your plants. More natural nutrients will have a lesser negative impact on flavor. 

While organic nutrient products are high quality, one con is that some organic solutions contain particles that can cause clogs in your hydro system. Synthetic/manufactured nutrient products won’t clog your water pumps or hydroponic tubing as readily. They are also released faster than organic nutrients in solution.

Hard vs. Soft Water Nutrients

Hard water has high amounts of minerals such as calcium and magnesium. Soft water is free from these minerals. How hard or soft your water supply is depends on your water supply. Understanding your water hardness levels is crucial for mixing hydroponic solutions properly because it affects the solution formula. 

Hydroponic Supplements and Additives

Depending on the crop, certain additives and supplements are sometimes needed to sustain plant development and support overall growth. While base nutrients are like a plant’s daily puppy chow that they eat every day, supplements and additives are more like pumpkin powder or heartworm pills that you give to your pup as needed, for a specific purpose, when they need a little extra care. They come in a variety of formulas with different objectives. Some basic hydro supplements include bloom boosters, CalMag, root stimulators, and flushing agents

Monitoring and Adjusting Your Nutrient Solution

Growers need to keep tabs on several measurements that affect nutrient uptake. The individual amounts of hydroponic nutrients required for yielding are known as nutrient uptake. This process is administered at the plant roots and acts as an entryway for taking in nutrients.

To help with nutrient uptake, we recommend grow formulas designed for the vegetative stage in plant development. Grow nutrients facilitate healthy photosynthesis respiration and enhance stalk and root growth to stimulate rapid bud production.

hydroponic nutrients guide

pH Levels

pH stands for potential hydrogen, which measures how acidic or basic a substrate is. Depending on your plant’s unique needs, the best pH for your solution for hydroponics is typically between 5.8-6.5. To measure the pH levels of your water, you will need a pH meter or a complete pH calibration kit. 

EC Levels

EC stands for electrical conductivity. It is a unit of measure in your nutrient solution. Also known as conductivity factor (CF), it’s used to understand the precise amount of nutrients in the water. The EC levels will increase throughout the plant life cycle, and the required measurements vary on crop types. EC calibration kits help manage EC levels for your indoor hydroponics system efficiently.

How to Add Nutrients to Hydroponic Systems

Since nutrient kits are highly concentrated, growers only need to add a specific, carefully measured amount to their hydroponic system. Adding nutrients to hydroponic systems requires tools such as meters and dosers to get the exact measurements necessary. 

Troubleshooting Hydroponic Nutrient Problems

Incorrectly mixing hydroponic solutions is a common misstep made by novice growers. Improper measurement and calculations can cause toxicity or deficiency issues. However, once you set up the right nutrient system, the maintenance process is streamlined moving forward. If you mix too much nutrient concentrate into your water, add more water to dilute it and restore the right pH level.

Shop GrowGeneration’s Huge Selection of Hydro Nutrients and Supplements

With the right hydroponic system and nutrient solution, you can grow almost anything indoors – even in winter. Now that you’re more familiar with our hydroponic nutrients guide, it’s time to start shopping for your nutrient supplies. 

At Grow Generation, we offer various hydroponic nutrients, supplements, and additives to fit your needs. Browse our selection of hydroponic nutrients or find them at a store near you.   

Grow Generation Editorial 


Inline Feedbacks
View all comments

Related Articles