The Essential Hydroponic Nutrients for Plants: What You Need to Know

Hydroponic Nutrients.

A hydroponic garden is a great way to grow your own plants without having to worry about soil. But what hydroponic nutrients do you need?

Keep reading to see our essential nutrients list, and how to use them.

The hydroponic nutrient solution is the most important aspect of how well your plants will grow.

Without it, they won’t be getting the proper nutrition that they need in order to thrive!

They are composed of macronutrients (nitrogen, phosphorus, potassium) as well as micronutrients (iron).

The key hydroponic nutrients you need to know about

Here’s everything your plants need to thrive:

Primary Macronutrients

  • Nitrogen (N) – Promotes healthy, green plant growth.
  • Phosphorus (P) – Help strengthen the roots and helps with flowering/fruiting plants.
  • Potassium (K) – Helps maintain a steady supply of sugars to your hydroponic plants which helps them grow as quickly as possible!

Secondary Macronutrients

Calcium, Magnesium, Sulfur, Iron, and Copper. Micronutrients are also present but only needed in tiny amounts such as Chlorine, Manganese Zinc, and Boron.


Micronutrients in hydroponics refer to elements that plants need for healthy growth, but only in very small amounts.

So, chlorine (Cl), manganese (Mn), iron (Fe), and zinc (Zn). The micronutrient Boron is often added as a nutritional supplement because it works as a natural antioxidant and increases cell wall strength.

Liquid Nutrients

Using liquid nutrients in hydroponics guarantees that your plants get the nutrients they need.

Liquid fertilizers provide all of the essential macronutrients and micronutrients for healthy growth in a form that is easily absorbed by plant roots.

Dry Nutrients

Dry nutrients are usually cheaper to buy initially, but they require more work to maintain since you need to mix them into your reservoir regularly using pH-adjusted reverse osmosis (RO) water solution.

Liquid vs Powder Nutrients

Which is better, dry nutrients or liquid nutrients? Well, that depends on your grower and what kind of hydroponic system you’re using.

Dry nutrients are great for drip systems because they don’t require much setup or regular maintenance, but liquid fertilizers work better with other types such as ebb-and-flow and deep water culture setups.

But liquid nutrients, on the other hand, although more expensive initially, offer superior nutrients that will help your hydroponic garden thrive.

Water Top-ups And Changes

Changing your water level is another important aspect of hydroponics that can make or break your growing project.

Hydroponic systems require you to top up the water level in reservoirs and change it out entirely at least once every two weeks. If you don’t do this, toxic salts will accumulate around plant roots and cause problems with nutrient uptake while also limiting the oxygen supply.

This is why you need to check pH levels regularly so that they stay within the range of between five and six. This will ensure your plants get optimal nutrient uptake while keeping them safe from toxic salt build-ups.

Keep in mind that some systems require more frequent water changes than others like ebb-and flow setups for example.

How To Choose Hydroponic Additives

Hydroponic additives are used for a variety of different reasons.

They are used to change the pH balance, nutrient concentration levels and water salinity.

If you’re using a hydroponic system for the first time, you will probably want to buy base nutrients that come with additives so you don’t have to worry about which ones are best just yet.

1. Flower Boosters

These types of additives increase the number of essential oils and terpenes in your plants.

They can improve a plant’s taste, smell, and color while also increasing weight yield. They’re great for use with flowering plants!

2. Mycorrhizae

Mycorrhizae are beneficial fungi that live in plant roots and help to transport nutrients.

They can also increase nutrient uptake, improve soil structure, protect against disease-causing pathogens, and increase drought tolerance.

3. Enzymes

Enzymes are used to increase nutrient uptake and transport.

They can also improve the health of your plants by protecting against pests, pathogens, and environmental stressors.

4. Vitamin B1

Vitamin B is also known as thiamine, and it helps with photosynthesis.

It’s often used during the early stages of plant growth because it protects against root rot in young plants. It can also increase flower formation.

5. Root Stimulants

Root stimulants are used to promote the growth of root mass and increase nutrient uptake.

They can also decrease transplant shock, germination time, and speed up seedling growth rates.

6. Sweeteners

Sweeteners are used to increase the sweetness of your plants.

They can also improve their smell and color, boost weight yield, and increase essential oil production.

7. Flushing

Flushing agents are used to remove excess nutrients from your system.

They’re usually added near the end of a plant’s life cycle before harvest so that they don’t affect their taste or weight yield negatively.

They can also be used during growing phases if you want to reduce salt levels in your water reservoir, which will increase nutrient uptake and growth rates.

Vegetating and Flowering Plants

There are some plants that grow better hydroponically than others.

Vegetating plants like lettuce, kale and spinach do not need to be rooted in the soil so you can use them with any type of system including ebb-and-flow or deep water culture setups. They also thrive when their roots are regularly cut back during the growing process.

Flowering plants that have a longer root system are best suited to deep water culture setups. These include tomatoes, peppers, and cucumbers.

Tomatoes in particular require a lot of regular pruning because they’re heavy feeders so you will need to cut their roots back regularly according to how much foliage is being produced by the plant.


Hydroponic fertilizers are generally designed to give your plants everything they need to grow in just the right quantities.

This is why you should only use a hydroponic fertilizer that are specifically made for hydroponics because regular ones will not be absorbed properly by plant roots and could lead to toxic salt build-ups or nutrient deficiencies (which look like yellowing leaves).

There are three main types of hydroponic fertilizers that are typically used in grow operations.

They are:

  • Quick Release Fertilizers
  • Controlled Release Fertilizer
  • Liquid Organic Fertilizers

Can you make your own hydroponic nutrients?

There are companies that make their own hydroponic nutrients. However, it is cheaper to buy ready-made fertilizers than try and create your own nutrient mix in a lab.

If you’re interested in making your own fertilizer though, all you need is some phosphate rock, potassium sulfate (a type of superphosphate) and potassium nitrate (saltpeter).

Mix these three ingredients at a ratio of one part phosphate rock to two parts superphosphate and five parts saltpeter.

Add in some magnesium sulfate to increase the absorption ability, but don’t add anything else! These ratios work well for both vegetating plants like lettuce, kale, and spinach as well as flowering plants like tomatoes.

Use this fertilizer at a rate of 0.25 to one pound per square foot on your grow area floor which equates roughly to 20-30 grams for every ten gallons of growing medium. Keep in mind that fertilizers will not be absorbed properly unless you mix them into the water.

Do you have to use nutrients in hydroponics?

Yes, and the reason is simple.

Plants use nutrients to grow and without them, they won’t be able to absorb water so there is no way for the plants to live.

Since hydroponics requires you to give your plants everything they need in just the right quantities, it is essential that you know what nutrients are needed for each stage of growth before using them.