Can I Use Regular Fertilizer For Hydroponics?

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By Alex Harris

The question of whether or not you should use regular fertilizer for hydroponics has come up before.

Regular fertilizers are made to be used in soil, but many people wonder if they can also be used in the water that plants grow in.

The answer is yes, but DON’T.

Regular fertilizers can kill your plants because they do not contain nutrients that are appropriate for a hydroponic system.

There are many different types of fertilizers available for this type of growing system, so make sure you choose one that is designed specifically for it!

Also Read: How Often Should I Give Add Nutrients To My Hydroponic System?

Why shouldn’t I use regular fertilizer for hydroponics?

Many people use regular fertilizers to grow plants in water, but this is not a good idea.

Regular fertilizers are designed to provide nutrients gradually over time and need soil to help them stay mixed with the water.

When you use it in your hydroponic system, it will release too much of a certain nutrient at once and burn the plants.

Since you are providing all of your plants’ nutrients through water, regular fertilizer can cause root burns or other problems.

Regular fertilizers will not provide the right types of organic nutrients for hydroponics systems either!

What fertilizer is good for hydroponics?

The best hydroponic fertilizer is one that is formulated to provide the nutrients needed for your plants without adding any unnecessary chemicals.

The fertilizers are available in dry powders, liquids, and granular forms.

They do not contain salts or other additives that could be harmful to your plants, so they will work fine with hydroponics systems.

We like Fox Farm and General Hydroponics as these guys provide a lot of options and their products are highly rated by experienced hydro growers.

Can I use soil nutrients in hydroponics?

You can use a soil fertilizer in your hydroponics system, but you should refrain from using a regular one.

Soil fertilizers are made to gradually release nutrients into the soil and therefore work best when used on land plants.

When these types of fertilizers are added directly to water, they will give too many nutrients all at once, which can burn your plants.

Instead of using the soil fertilizer you already have at home, why not just buy one that is specifically designed for hydroponics?

Regular Fertilizer and the dreaded hydroponic salt buildup

The most important reason for not using regular fertilizer is the salt build-up that can occur.

When you apply a normal fertilizing routine with a high nitrate nutrient solution, it will cause calcium and magnesium to be pulled from the hard water deposits in your pipes causing white powdery buildup everywhere.

This white dusting on all of your equipment will cause an immediate need to clean everything down before the next grow.

Regular fertilizers are not made for hydroponics systems and can burn your plants when used with them.

The best types of fertilizer for this type of growing system are one that is specifically designed for it, like dissolving in water nutrients or dry nutrient powders.

Also, make sure to buy a fertilizer that is designed for your specific plants’ needs.

Regular fertilizers do not provide the right types of nutrients and can cause buildup in hydroponics systems.

Flower drop when using regular fertilizer

This is a big one.

When using regular fertilizer in your hydroponic system, you are likely to get flower drop (stunted plant growth) at some point.

Regular fertilizers have high amounts of potassium which will cause the plant to stop flowering so it can gather more nutrients from the soil before continuing its growth cycle.

Instead, use a hydroponic fertilizer that is designed for your specific plants’ needs.

Using regular fertilizers can result in a buildup of salts, causing damage to the roots and plant burn.

It also causes flower drop when used with blooming crops like cannabis or tomatoes/peppers because it contains high potassium which will stop flowering so nutrients can be absorbed from the soil.

The 20-20-20 fertilizer rule you must follow

A simple rule to remember is to buy fertilizers with the numbers 20-20-20.

This means that there are equal parts of nitrogen, phosphorus, and potassium in your fertilizer.

To find out how much you need for each nutrient in your plants, check the label on your container.


Even if you have regular fertilizer lying around in the shed, don’t consider using it for hydroponics.

Regular fertilizers are not good for plants grown in water and can even kill them in some cases, so it’s not worth the risk.

There are many different types of fertilizer specifically designed to be used with this type of growing system, which is why you should buy one that works best for your situation.