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8 Reasons Why Houseplants NEED Fertilizer (Explained!)

You have probably read everywhere that fertilizing your houseplants is very important. It is universally recommended for your plant’s health.

However, you might also know that plants take all their required nutrients from the soil. So, when it comes to fertilizer, why do houseplants need it if they are so self-sufficient?

In this article, I will tell you all the reasons why it is recommended to fertilize houseplants, as well as answer all the facts you need to know about it.

Here are the most important reasons why houseplants need fertilizer:

1. Fertilizer Feeds Your Plant

Fertilizer’s main job is, of course, to feed your plant. Plants require certain nutrients if they are to grow well and build new leaves, stems, roots, and flowers. Although they do get energy from sunlight and turn this into food, they must also have access to nutrients in the soil.

Your plant’s compost will contain these nutrients to begin with, but as the plant grows, it will gradually deplete them.

It will deplete the ones it needs the most faster than others, so it’s very important to keep your plant fertilized if you want it to keep growing well.

2. Fertilizer Makes Your Plant Insect Resistant

Happy, healthy plants are less likely to get attacked by insects, so fertilizing your plant regularly is a good way to keep it safe from insects.

Of course, that isn’t to say you will never see aphids, scale insects, spider mites, or other pests on a plant as long as it is well fed, but if your plant is sickly and hungry, it is more likely to suffer from pests because its natural defenses will be down.

You should therefore make sure that you feed your plants regularly when they are growing, to discourage pests from bothering them.

3. Fertilizer Encourages Healthy Microorganisms

Fertilizing your plant’s soil makes it rich and healthy, as outside soil should be. Soil in nature is constantly enriched by decaying plant matter and dead animals, so it’s full of food for microorganisms. These microorganisms can be beneficial to your plants.

Indoor soil does not get enriched in the same ways, and it is therefore not as hospitable to microorganisms.

Some of these microorganisms are beneficial to your plants, so creating a good environment for them will help your plant to stay happy and healthy.

4. Fertilizer Saves Your Plant Energy

This one might sound odd, but if your plant is constantly struggling to find more nutrients in soil that is poor, it is using up energy unnecessarily. It will keep soaking up water in the hopes of getting the minerals it needs, but if they aren’t there, this is a waste of its other resources.

By keeping the soil rich, you save your plant this energy, and may reduce its stress levels, because it has everything it needs readily available.

This lets it focus on growth.

5. Fertilizer Helps Reduce The Risk Of Diseases

Just as a healthy plant is more resistant to pests, it is also more resistant to diseases. Plants that are suffering from deficiencies are much more likely to get sick, because they don’t have the nutrients that they need to grow strong and healthy.

Think of this working just as it does for people. A diet that is lacking in the necessary vitamins and minerals leaves a person exposed to more diseases, and less capable of recovering from them.

If your plant doesn’t have the food it needs, it is more likely to get sick, and less likely to recover.

6. Fertilizer Makes The Soil Suitable

In some cases, your soil might be rich in some nutrients, and deficient in others. Adding fertilizer is a good way to balance it and ensure that it is suited to your particular plant. For example, if your plant uses lots of potassium, it will soon use up everything that is in the soil, and its soil will no longer be suitable for it.

Fertilizing the soil will help to make it more suitable and encourage your plant to grow strong.

It will also ensure that the soil is similar in terms of structure and microorganisms to the soil your plant would naturally grow in, and this should make the plant happier.

7. Fertilizer Encourages Leaf Growth

Many kinds of fertilizers will help your plant to develop new leaves, and this can prompt more growth overall. If your plant is not putting out enough leaves, a good dose of fertilizer may help to correct this.

It is the nitrogen in fertilizer that encourages leaf growth, and adding it to your soil will give your plant a boost.

With more leaves, it can photosynthesize more effectively, and this will give it more energy from sunlight that it can put into its roots, shoots, leaves, and flowers.

8. Fertilizers Create A Standard Quality Soil

When you fertilize your soil, you make sure that it is up to a certain standard and has all the nutrients that are needed for a plant.

You give yourself peace of mind that the plant isn’t lacking in something it needs.

Using a suitable fertilizer regularly ensures that your plant always has access to the right levels of nitrogen, potassium, and phosphorus, so it’s a good way to ensure that your plant thrives year after year without having to worry about it.

What Happens If You Don’t Fertilize Houseplants?

Your plant will not usually die if you don’t fertilize it, but it may significantly slow down its growth, and its leaves might turn pale. It may flower too early, with just one or two blooms, and then do little else throughout the year.

You might also observe wrinkled, small foliage.

Can Houseplants Survive Without Fertilizer?

Yes, most houseplants can survive without any fertilizer, at least for a few years. Fertilizer is needed for houseplants because they are constantly using up the nutrients in their containers as they grow.

After a while, the soil will get heavily depleted of the nutrients your plant requires. Furthermore, when you water your plants, nutrients will be washed out of the container and into the saucer underneath, beyond the reach of the plant.

Do All Houseplants Need Fertilizer?

Not all, but most houseplants need fertilizer. There are a few exceptions to this rule. Plants that like very poor soil will not appreciate being fertilized and in some rare cases, it could even kill them.

For example, the Venus Flytrap does not like to be fertilized, because it gets the nutrients it needs by trapping insects. Rich soil will burn its roots and kill it.

If you want a list of houseplants that never need fertilizer, I have just the article for you.

What Kind Of Fertilizer Do Houseplants Need?

There are three major kinds of fertilizer: granular, slow-release, and liquid. All of the have the same purpose, but many people prefer liquid because it’s easier to dilute and it spreads throughout the container.

With liquid fertilizer, it’s also easier to adjust how much you give the plant, adding different amounts for different plants.

What Fertilizer Is Best For Houseplants?

Plants have different needs when it comes to fertilizer, so it’s often a good idea to research your specific plants before you choose which fertilizer to use. As a general rule of thumb, all-purpose fertilizers tend to be suitable for most houseplants and can be given to them as needed.

However, some plants benefit from having higher doses of certain nutrients, and you may want to use a fertilizer with unequal ratios.

The numbers on the front refer to the three main nutrients, nitrogen, phosphorus, and potassium. NPK 20-20-20 means the fertilizer contains 20 percent of each of these nutrients.

Choosing the specific ratio your plant likes best is a good idea, and will give it the best chance of healthy growth.

Non-flowering plants tend to prefer higher levels of nitrogen, for example. Flowering plants may prefer a balanced fertilizer or one that is high in phosphorus, which specifically boosts their ability to bloom.

There is therefore no “best” fertilizer for all plants; you will need to choose according to the plant you are growing and the kind of growth you want to see.

How Often Do Houseplants Need Fertilizer

You will often be fertilizing your houseplants throughout their growing season, as often as every 2 weeks or 1 month. Use your plant’s label to find out how much food it needs, how frequently to offer it, and what kind of fertilizer to choose.

You may want to dilute it if you are using liquid fertilizer, but always read the instructions provided.

How Much Fertilizer Do Houseplants Need?

There is no general guide on how much fertilizer to use on your houseplant because needs will vary from plant to plant. Some are much hungrier than others. Research the recommended feeding schedule for your specific plant and follow this.

Also remember that it is better to fertilize too little than to over-feed your plant, as concentrated fertilizer will burn its roots and make it stressed.

When Should You Fertilize Indoor Plants?

Most indoor plants need to be fertilized throughout their growing season, which tends to be spring and summer (although a few plants will grow more in the winter).

You should stop feeding them when they reach the end of their growing season, as there is a risk of the fertilizer building up in the soil and burning the plant’s roots.


Houseplants need fertilizer for a variety of reasons, but mostly because it is crucial if they are to continue growing healthy, strong foliage.

Consistently poor soil will stunt your plant’s growth and may leave it vulnerable to pests and diseases in extreme situations, so make sure you feed your plants according to the recommendations.

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