A Q&A Guide on Hydroponic Fertilizers – What to Know

Growing plants hydroponically is arguably a bit more complex than growing them in soil. This leads to plenty of confusion regarding the subject, and growers often unwittingly make mistakes that cause their plants to grow poorly or eventually die.

When it comes to fertilizers specifically, many hydroponic growers are uncertain about their use. This is what we aim to clarify in the sections below. We’ve gathered some of the most common questions regarding using fertilizers in hydroponic systems to give you the answers that you seek.

Q: Can I use regular fertilizer for hydroponic plants?

A: While it is possible to use regular fertilizers in hydroponic systems, we advise you to purchase fertilizers that are specifically designed for this type of growing medium. Regular fertilizers may lack or contain excessive amounts of certain compounds that will prevent healthy growth.

Q: How do I use fertilizer in my hydroponic system?

A: Hydroponic fertilizers usually are in liquid form. You basically just pour the correct amount of the fertilizer directly into your system. However, you must be careful with the amount you use, as too much can effectively kill your plants. We suggest that you follow the instructions on the product label to be certain.

Q: How often do I need to add fertilizer to my system?

A: Again, it’s best to follow the instructions on the product as different fertilizers will have their specific fertilizing schedules. However, a general rule of thumb is to base the frequency of fertilization on the nutrient levels present in the water. This is done by testing the EC (electrical conductivity) of the water, which pertains to the proportion of dissolved compounds in the water. When the EC dips below a certain level, this indicates that there aren’t enough nutrients in the water and you need to fertilize again.

Q: Do all plants require the same amount of EC?

A: No. Different plants will thrive in different levels of EC. For instance, basil and most other herbs thrive in EC levels ranging from 0.8 to 1.4. Spinach, on the other hand, can tolerate EC levels many times greater, up to a maximum of 3.5 This is why it’s important that you research beforehand on the amount of fertilizer a plant needs, and continue to check the water regularly to ensure healthy growth.

Q: Is fertilizing necessary in hydroponic systems?

A: Yes. The absence of soil means that hydroponic plants will require you to provide additional nutrients via fertilizers to sustain plant growth. These fertilizers essentially act as plant food, giving the nourishment that plants need to grow healthily.


We hope this guide clarifies the use of fertilizers with your hydroponic systems. As stated earlier, fertilizers are essential to this type of growing method, so knowing more about how they work is especially important.

To make your fertilizer more effective, however, we recommend supplementing it with natural plant growth enhancers that promote better nutrient absorption. Our products are designed to work with any type of fertilizer by boosting your plants’ ability to feed themselves, allowing them to grow stronger and more resistant to disease.

Visit our store if you’d like to purchase our hydroponic plant enhancer or other products, or get in touch with us if you’d like to learn more. We’d be more than happy to help.