What Is Houseplant Fertilizer

The majority of fertilizers for houseplants are a blend of macro- and micronutrients. On the face of the bottle or bag, the ratios of the three main macronutrients nitrogen, phosphorous, and potassium that can be found in a container of fertilizer are mentioned. These figures, known as the N-P-K ratio, indicate the proportion of each of those nutrients in the container. Given that each of these kinds of plants has different nutritional requirements, the ratio of these macronutrients in a tomato fertilizer or a lawn fertilizer is different from the ratio found in a houseplant fertilizer. This means it’s essential to use fertilizer designed especially for houseplants. When buying fertilizer for houseplants, that should be the first thing you check for. For houseplants should be printed somewhere on the box.

The middle number on the container, phosphorus, is necessary for flowering. Fertilizers for houseplants that flower ought to contain a little bit more phosphorus (1-3-1, for example). Those used to green houseplants that don’t frequently flower should have a little more nitrogen. They might also have a healthy balance of nutrients (5-3-3 or 5-5-5, for example). For my flowering houseplants, I usually use one fertilizer, and for my non-flowering ones, I use a different one. Unless you are cultivating flowering houseplants like African violets, begonias, or gloxinia, you don’t need to do this.

Numerous fertilizers, but not all, also contain micronutrients like iron, zinc, and boron, as well as secondary macronutrients like calcium and magnesium. Even though these nutrients are used in smaller amounts than the major macronutrients N, P, and K, every plant nevertheless needs them to function properly. Make sure your fertilizer for indoor plants includes a trace amount of these nutrients as well.

What ingredients are in houseplant fertilizer?

You may buy a variety of excellent liquid fertilizers for houseplants as well as gently releasing dry formulations.

Here are the natural fertilizers that contain one of the three basic macronutrients:

proper dosages of each to seek out:

  • Fish: Nitrogen
  • Rock: Phosphorous
  • Calcium: Kelp meal,

How should I fertilize my houseplant?

You are aware that indoor plants require water and sunlight, but what about fertilizer? Fertilizing indoor plants during the growing season can provide them the nitrogen (N), phosphorus (P), and potassium (K) they require to thrive (K).

Similar to learning how to repot a plant, feeding your houseplants can seem intimidating at first. However, after you master the fundamentals, you’ll wonder how your plants ever survived without it. The numerous types of fertilizer available, what fertilizer is (hint: it’s not plant food), and how and when to fertilize houseplants are all covered in the sections below.

What is fertilizer?

First and foremost, plants do not eat fertilizer. Photosynthesis is the process through which plants produce their sustenance while utilizing sunlight. Fertilizer promotes fresh, healthy growth in a similar manner to a multivitamin. Additionally, it can be utilized to replenish the vital minerals that our plants’ potting soil loses as they mature. The main ingredients, or macronutrients, in fertilizers are nitrogen (N), phosphorus (P), and potassium (K), which we will discuss in more detail later. Fertilizers can also contain a variety of other nutrients.

When should I fertilize my houseplants?

like excessive amounts of light or water Your plants may suffer if you use too much fertilizer. During the growing season, which runs from early spring to late summer, we advise fertilizing indoor plants moderately. Plants will gain the most from new nutrients at this period, while they are actively growing. Depending on the fertilizer you’re using, you can typically fertilize your plants monthly or every other week. Read the label carefully because each brand may have a different suggestion for dilution and timing.

Fertilizer will not help newly potted or repotted plants. They haven’t even begun to use all the nutrients in their fresh potting mix! Wait 23 months after a fresh repotting before fertilizing actively growing plants during the growing season to prevent potentially harming recently replanted plants. You can postpone fertilizing until the following growing season if you potted during the autumn and winter.

Because of their decreased metabolic activity, plants in low-light conditions don’t require fertilizer. They don’t consume nutrients as efficiently as individuals who are in brighter light.

What do the numbers on fertilizer mean?

Three of the approximately 17 necessary plant nutrients are prominently featured on the front of the majority of fertilizers. The N-P-K ratio is represented by the three numbers you see: N stands for nitrogen, P for phosphorus, and K for potassium. The main macronutrients that your plant requires are these.

A fertilizer label can include an N-P-K ratio that looks like 10-5-8. Higher ratio fertilizers are more concentrated than lower ratio fertilizers. Do not assume that a fertilizer with greater numbers is superior than one with fewer numbers just because it has higher numbers. It just needs more water to be diluted with because it is more concentrated.

Micronutrients could be included in your fertilizer, making it a complete fertilizer. These can contain things like chlorine, iron, manganese, zinc, copper, boron, and molybdenum. Each micronutrient plays a part in the cellular, enzymatic, and developmental processes of plants, but they are not as essential as the NPK macronutrients. Your fertilizer’s micronutrient content will probably be listed on the back of the container.

For your indoor plants, you can use any all-balanced fertilizer (for instance, 5-5-5) or one with a ratio that fits the goal you want to achieve. In order to stimulate leaf production, for instance, a fertilizer with a higher nitrogen to phosphorous ratio is best, whereas a higher phosphorous to nitrogen ratio aids in promoting fruiting and blooming.

Is solid or liquid fertilizer better?

There are various types of fertilizers. It is mainly a matter of preference when selecting the type of fertilizer to use. Both give the vital nutrients that plants require, yet they each have advantages and disadvantages.

The two types of fertilizers used most frequently for indoor plants are liquid and powder. They may also be the most economical depending on how concentrated they are, or how high their N-P-K ratio is. Fertilizers in liquid and powder form are also simple to use and diluted in water. You can also immediately add a variety of powder fertilizers to the potting soil.

Perhaps less frequently used for houseplants are solid fertilizers, sometimes known as dry or granular fertilizers. Because some granular fertilizers (fertilizer pellets) release nutrients over time, you run the risk of overfertilizing a plant or fertilizing it when it is dormant or growing slowly because of poor light.

Is chemical or organic fertilizer better?

Another option is selecting between synthetic fertilizers, commonly known as chemical fertilizers, and organic fertilizers. The macro and micro nutrients in synthetic fertilizers are typically more precisely balanced and concentrated. They might be more affordable, particularly if you buy them in liquid form to dilute. With less, you can obtain the same amount of nutrients.

Organic fertilizers are typically less concentrated because they are created from all-natural components, such as reprocessed food waste. However, mild is a benefit, not a drawback, of houseplant fertilizer. Although it can be slightly more expensive than other forms, organic fertilizer is a safe, chemical-free choice. Choosing an organic fertilizer may be the finest option if you have pets who share your space.

Chemical and organic fertilizers both supply nitrates, potassium ions, and phosphates to plants, but in different ways. It strikes a balance between your personal preferences and those of your plants.

Quick Tips for Fertilizing Houseplants

First tip: Since plants begin to actively grow in the spring, it is the optimal time to begin fertilizing them. Fast-growing plants should get fertilizer more frequently than slower-growing or dormant plants, such as cacti (i.e., most plants in winter.)

Second tip: Dilute your fertilizer. Less fertilization is preferable to more fertilization. If the potting mix is deficient in nutrients and you haven’t fertilized in about a year, you can improve the efficacy of the fertilizer by diluting it with less water.

3. Plants that produce fruits or flowers over their lifetimes will need extra fertilizer. Picking off fruits or flowers depletes them of their nutrients, which we should replenish.

Know your N, P, and K values. The ratio of macronutrients that should be present in your fertilizer is the one that your plant requires. It resembles the numbers 10-8-10. Find another fertilizer if this isn’t stated on the package.

5. Plants only require a smaller amount of micronutrients than they do of macronutrients, notwithstanding their importance. Micronutrients are typically present in fertilizers, however they aren’t usually highlighted on the front of the fertilizer container.

How should indoor potted plants be fertilized?

You can manually incorporate dry, pure fertilizer pellets into the potting soil. They can be utilized for indoor containers, despite being more frequently used in outdoor gardens, however it might be challenging. Granular fertilizer is difficult to control because it releases all of its nutrients simultaneously when the pot is watered. Although fairly affordable, this kind of fertilizer is not a good option for feeding indoor plants.

Should indoor plants be fertilized?

As a general rule, only fertilize indoor plants when they are actively growing. While they are dormant, feeding them might cause their foliage to burn or even result in their death.

Don’t overfertilize your plants. Follow the instructions on the product you’re using because using too much can be just as bad as using too little. You should halve the concentration of liquid fertilizers if you want to be safe.

How frequently should indoor plants be fertilized?

When indoor plants are actively growing in the spring and summer, fertilize them. Use a fertilizer that is complete and contains potassium, phosphorus, and nitrogen. Fertilizers for indoor plants can be found in liquid, crystal, granular, spike, and tablet form. Depending on the product, application frequency might range from once every two weeks to once every three to four months. Read the directions on the label attentively.

During the winter, avoid fertilizing indoor plants. Winter is when most indoor plants do not grow vigorously and do not require fertilization.

How can I prepare nourishment for my house plants?


For this dish, a used plastic milk jug works well as the serving vessel. Your container should now contain all of these components. Allow it to settle for around 30 minutes. Your solid materials will have time to dissolve as a result.

So that the plant’s roots can effectively absorb the nutrients, add plant food straight to the soil. Once a month is a good place to start, then you can gradually increase how frequently you feed your plants based on how they react.

How can I manufacture food for indoor plants?

In a fresh gallon jug, add 1 1/2 tablespoons of Epsom salt. This DIY plant food can be stored in a cleaned-out plastic milk jug with lid.


A tiny 1/2 teaspoon of household ammonia should be added to the jug. Scant refers to a small fraction of a teaspoon. Avoid using too much ammonia; a little bit goes a long way!


To enable the Epsom salt to completely dissolve, allow to sit for at least 30 minutes. Label the container and keep it out of the reach of children and pets in a cold, dry place.


Although it may seem that mulching is simply something you do for outdoor plants, your indoor plants don’t mind either. Mulching can help you keep your indoor plants healthy and hydrated depending on what you add to the mulch.

Straw or compost are two examples of organic materials that make for good houseplant mulch. Coffee grounds can also be included in your DIY mulch mixture, but moderation is key.

This is one situation where drinking a lot of coffee won’t help. Over time, accumulating coffee grinds around seeds or the plants themselves might harm your plants’ health.

Also, the caffeine in the coffee grounds may prevent your plants from growing to their maximum potential. Additionally, the coffee that chokes your plants makes it difficult for nutrients to penetrate.

You should wait till the plants are more mature before mulching with coffee grounds if you’re specifically raising seedlings that haven’t yet sprouted. Keep an eye on your plant even after it reaches maturity.

Also, don’t believe the myth that worn coffee grounds contain less caffeine than fresh grounds.

When the Department of Nutrition, Food Science and Physiology, School of Pharmacy at the University of Navarra evaluated the amount of caffeine in used vs unused coffee grounds, the used grounds still contained caffeine, ranging from 3.59 to 8.09 mg, according to Caffeine Informer.


Only using coffee grinds as a pesticide is preferred by some indoor (and outdoor) gardeners. This works well, especially with slugs. Slugs won’t enter your houseplant as long as coffee grounds are scattered over the soil.

The texture of the coffee grounds will, at the very least, deter slugs. This is comparable to sprinkling cracked eggshells across the soil to deter snails.


Fertilizer is by far the most common application for coffee grounds in indoor gardens. Coffee grounds contain nitrogen, phosphate, potassium, and other micronutrients in addition to their nitrogen content. For some types of houseplants, this makes them an excellent choice for a slow-release fertilizer.

Applying the coffee grinds to the soil of your houseplant to fertilize it requires a light touch. Consider it in terms of “less is more.”


Try adding the coffee grounds to your compost pile as an alternative if you wish to err on the side of caution and avoid directly applying coffee grinds to your houseplants.

The nitrogen and carbon in coffee grounds will draw worms and microbes to your compost, allowing it to decompose more quickly and maintain its nutrient-rich state.

However, don’t just throw in coffee grinds. They should make up about 20% of the ingredients in your compost, so you should keep them.

Water Alternative

You didn’t complete your morning’s second cup of coffee. That is not an issue. When you’re through drinking that cup of coffee and it has had time to cool, you can use the liquid coffee to water your plant in place of water.

Tip the coffee cup or pot so the liquid falls on the ground rather than the foliage or blooms of the plants. Use less coffee the following time or maybe avoid it completely if your houseplant’s leaves turn brown at the edges after the coffee application.