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10 Best Fertilizers for Indoor Plants in 2023 – Reviews & Top Picks
Kristin Hitchcock
Last updated:
Fertilizing potted plants is a must if you want them to last long. Because these plants are in a very contained environment, they won’t last very long unless their nutrients are refilled. The soil won’t replenish naturally as it would outside, so we have to provide these nutrients ourselves.
However, this isn’t always a straightforward process. There are a lot of fertilizers out there, and not all of them are suitable for indoor plants. Therefore, you have to choose the correct fertilizer for your indoor plants.
Below, we’ve written 10 reviews for the best fertilizers for indoor plants on the market.
Generally, we recommend Miracle-Gro Indoor Plant Food for most indoor plants. It instantly begins feeding indoor plants, curing potential deficiencies within a very short amount of time. Plus, you can use it for all indoor plants, including those that you eat. It is safe for people when used as directed.
You can apply the mixture directly to the soil or mix it into water. This is rarely the case with liquid fertilizers, as they tend to burn roots when not diluted with water. Overall, this feature makes this plant food much easier to use, as you don’t have to worry about diluting it first.
Based on this feature, this fertilizer is easily the best overall fertilizer for indoor plants.
This fertilizer is made to be used once a week. It quickly feeds plants, but it doesn’t last very long. Therefore, you will have to reuse it often.
Pros
Can be mixed directly into the soil
Feeds instantly
Not expensive
Can be used once a week
Safe for edible plants
Cons
Doesn’t last long
2. Miracle-Gro Indoor Plant Food Spikes – Best Value
If you’re looking for something that is both cheap and easy to use, we highly recommend investing in these Miracle-Gro Indoor Plant Food Spikes. They are extremely easy to use and can be utilized for nearly all indoor plants, including that that you plan on eating. These spikes are long-lasting, unlike other fertilization options. They last for about 2 months before they need to be replaced.
This fertilizer includes everything that your plant needs to grow. Therefore, they work well when you’re looking to keep plants around for a long time or help them grow faster.
Furthermore, because of how these spikes are designed, they aren’t very visible so you won’t have to worry about how they look alongside your plant.
While these may cost more upfront, they will save you lots of money in the long run. Therefore, we highly recommend them as the best fertilizer for indoor plants for the money.
Pros
Inexpensive
Lasts up to 2 months
Includes all necessary micronutrients
Very low profile
Cons
Doesn’t provide instant fertilization
3. JR Peters 52024 Jacks Classic 20-20-20 – Premium Choice
JR Peters 52024 Jacks Classic 20-20-20 is a professional-grade fertilizer that should work well for most plants. It features an even formulation of nitrogen, phosphorus, and potassium. Therefore, it provides even and complete nutrition that works well for your average houseplant.
You can use this fertilizer on practically any plant, including those indoors and out. It is safe for edible plants, such as microgreens and fruits. This formula seems particularly helpful for foliage plants, as it encourages leaf expansion and rich, green colors.
For this reason, we highly recommend it for plants with large leaves.
This formula does require some mixing before it is ready for use. It must be added to water at a certain dilution. Therefore, it is a bit harder to use than other options.
For those looking for organic fertilizer, we recommend Joyful Dirt All Purpose Plant Food. This plant food works well for plant owners that want fertilization to be as easy as possible and good for the environment. All you have to do is shake this mixture directly onto the soil or mix it into the water. It doesn’t get much easier than that.
This fertilizer is specifically designed for indoor plants, specifically increasing foliage and reviving sickly plants. You can use it on practically any plant out there.
Plus, this fertilizer also uses mycorrhizae and other added nutrients, which seriously help improve a plant’s health. The company advertises that this formulation can help plants grow faster and reduces the amount of water they use.
The Marphyl Organic Liquid Fertilizer is extremely strong. It can be used both indoors and outdoors in nearly any situation. For instance, you can add it to your flower beds, hydroponics, or any other plant. While it may be a bit overkill for indoor plants, it is safe to use inside, especially when your plants really need help.
This fertilizer doesn’t just include the usual macronutrients. Instead, it includes vitamins, minerals, DHA, EPA, and essential fatty acids. All of these nutrients can help improve your plant’s help and cure a variety of nutritional deficiencies. Therefore, this formula is probably one of the most complete out there.
Plus, it is completely organic. It is safe for use outside and in your household, as it is completely non-toxic. It provides the fertilizer that your plants need without any harmful chemicals that your family doesn’t need.
You do need to dilute this formula a lot before use. Therefore, it doesn’t work great for homes with very few plants. Plus, this does add an extra step to consider when purchasing this fertilizer.
Compared to other options on this list, Osmocote Smart-Release Plant Food Plus is a bit different. It comes in pellets that degrade into your plant’s soil, releasing a variety of nutrients when they do so. This formula is fortified with 11 different nutrients, which is more than lower-quality formulas. All of these nutrients help your plants grow and thrive.
Plus, these pellets work for up to 6 months when used directly. This is a long-term option, as opposed to many instant fertilizers out there. You can use this formula for just about all plants—both indoors and out.
With that said, this formula does include microplastics. The pellets have a plastic shell that prevents them from breaking down before use. However, these plastics end up in your soil and groundwater. Indoors, this may be less of a problem. But, outside, it can potentially poison wildlife.
You’d think that indoor plants would be safe from insects. However, that isn’t always the case. BioAdvanced 701710 spikes are designed specifically to fertilize your plants while also killing insects that come near. You can only use them in pots for this reason, but that should cover all indoor plants.
This formula offers 8 weeks of protection from bugs without any need to spray. Plus, each pack comes with 10 spikes at a time, allowing you to treat 10 different plants. The food inside is released slowly for 2 months, as well. Therefore, you shouldn’t have to fertilize your plants until this period is up.
With that said, this formula isn’t the safest, as it includes lots of insecticides. Therefore, you may not want to use it on edible plants or in homes with families. Its sale is also restricted in certain states.
Unlike other formulas, Home Jungle Canopy Mist is designed to be used on a plant’s leaves. While you can spray it directly on the soil, it works best when you mist your plant’s canopy, as the minerals and nutrients can be absorbed through the leaf tissue. It provides very fast-acting nutrients to plants that need them—and it is completely safe for your family.
Because of the design, plants should absorb the mist almost instantly. Therefore, this formula doesn’t last long and you have to use it regularly. However, if you’re looking for a fast-acting option, this formula is about as fast as they get.
This formula works best when sprayed on leaves. Therefore, spray that lands on flowers, stems, or the soil may not be completely absorbed. You have to be a bit particular about where you spray it.
Earthpods are a pretty interesting form of fertilizer. They are designed to be pushed into the soil, where they slowly release their nutrients into the pot. They are designed solely for indoor plants, as they likely wouldn’t be as effective outdoors. These pods contain the nutrients you would expect fertilizer to contain.
The whole system is eco-friendly, which is great for those who have the environment in mind.
The main problem with these capsules is that you need to get them close to the roots. As you’d imagine, this can be a bit messy at times. Pushing a pod down into a pot is sure to leave dirt everywhere—or just be plain impossible.
Plus, this formula takes a long time to break down. Therefore, it doesn’t deliver nutrients quickly to plants that need them.
In many ways, the Fox Farm Organic Liquid Plant Food is extremely similar to other fertilizers out there. It features just about the same ingredients and works very similarly. This formula is specifically designed for flowers. However, that doesn’t necessarily mean that there is a ton of things differing this formula from an all-purpose option.
As the name suggests, this formula is completely organic. It doesn’t contain raw nutrients like most other formulas. Instead, it is a mix of organic ingredients that may be helpful for most plants. However, for this reason, it may not be as strong as other plants, and you can’t really know what’s in it.
This fertilizer is extremely safe, though. You can use it on plants you intend to eat and in most households.
Pros
Organic
Very safe
Cons
No specific nutrients included
A bit expensive
Not as strong as other formulas
Buyer’s Guide: Selecting the Best Fertilizer for Indoor Plants
There are tons of different fertilizers on the market. However, they aren’t all suitable for indoor plants. Plus, even those that are suitable for indoor plants vary widely. Therefore, not just any fertilizer will do. You need the fertilizer that will work best for your plant.
In this section, we’ll help you determine which fertilizer may work best for your plants, as well as how to use it effectively.
When to Feed Houseplants
While many fertilizers will advertise that you need to constantly feed your houseplants, this isn’t actually the case. If your plant needs to be fertilized, it will grow slower or not at all. However, for many plants, this is hard to notice.
You’ll need to research your particular plant and fertilize it according to its growing cycle. Not all plants grow at the same rate all the time. Therefore, you’ll need to fertilize your plant when it is growing the most.
What to Feed Houseplants
If you want to, you could get really complicated with your fertilizers. Technically, each species of plant has specific nutritional needs at different times. Based on these needs, you could specially formulate each plant’s fertilizer and fertilize it exactly when it needs to.
Luckily, though, you don’t have to be this exact. Truthfully, most houseplants need about the same nutrients at about the same time. Therefore, you can have most of your plants on the same schedule and fertilizer.
You may need to increase your amounts slightly for heavy feeds (and decrease it for lower feeders). However, generally, your plants’ needs are going to be extremely similar.
The N-P-K Ratio
Almost all fertilizers are characterized by their N-P-K ratio. These letters stand for the macronutrients that all plants need: nitrogen, phosphorous, and potassium. Generally, a fertilizer will have these listed so that you know exactly what you’re giving your plants.
The ratio different plants need varies quite a bit. Houseplants will need something very different from the grass in your yard. Therefore, you’ll need to purchase a fertilizer specifically for your houseplants. Nothing else will do.
Phosphorus is particularly important for flowering. Therefore, for plants that produce flowers, you may want a formula with a slightly higher phosphorus content. Plants that are very green but don’t produce flowers should consume more nitrogen, as it will help with their coloration.
While you can purchase fertilizers for each type of houseplant, many plants do just fine on a balanced formula. However, if you want to purchase two different fertilizers for your different kinds of plants, go ahead and do so.
Your fertilizer should also contain small amounts of minor macronutrients. While your plant doesn’t need as much calcium and magnesium as other nutrients, they do need them in small amounts. In the long run, you will have to add these nutrients back to your plant’s soil.
Image credit: Pratchaya.Lee, Shutterstock
Ingredients
Preferably, your houseplant’s fertilizer should contain natural sources of the nutrients they need. While chemical fertilizers are sometimes recommended, they are much stronger. They are more likely to burn your plant and aren’t the most eco-friendly option.
However, if you’re looking for a very strong fertilizer or one with very specific nutrients, then synthetic fertilizer may be your only option. We did include some synthetic fertilizers on our list, simply because they are still a good option in some situations.
Beyond that, the exact ingredients don’t matter. The nutrient amounts are much more important than the ingredients.
Types of Houseplant Fertilizer
There are a few types of houseplant fertilizer that you should keep in mind. Some of these are better in specific situations, while others should generally be avoided.
Liquid Fertilizer
Liquid fertilizer is easily the most popular option out there for the average houseplant. It is easy to find and comes in many different forms. You will need to use liquid fertilizers more often, as they are not time-release like granules or spikes.
Furthermore, the use of liquid fertilizers can help reduce the risk of burns. Excess fertilizer can simply run out of the bottom of the pot. While this is wasteful, it does prevent the excess fertilizer from sitting in the pot. Plus, water will wash out the fertilizer over time.
Granular Fertilizer
This type of fertilizer also comes in a few different subtypes. You’ll find both loose powders and hard pellets. The powders are often added to water or sprinkled directly onto the houseplant. The pellets are typically pushed into the soil, which can be challenging in some cases.
Sometimes, the pellets call for being placed directly next to the root system. As you’d imagine, this is hard if not impossible for many houseplants.
You can also find spikes, which are similar to pellets but in the form of a “spike”. You push this spike into your pot, and it slowly releases its nutrients. In this way, you can keep your plant fertilized for quite a long time.
Fast vs. Time-Released
Most fertilizers on the market quickly add their nutrients to the soil. Usually, this is instantaneous with liquid fertilizers. However, granular fertilizers may take a bit to dissolve and add their nutrients back to the soil.
Either way, these fast fertilizers get your plants the nutrients they need quickly. However, they can also be used up faster, since they are all available at one time. Regular watering will eventually remove these fertilizers from the soil, anyway.
On the other hand, time-release formulas don’t break down quite as fast. Instead, they dissolve slowly and release their nutrients over a period of time. Therefore, you won’t have to retreat your plants quite as often. However, if your plant needs a nutrient now, then these types of fertilizers aren’t usually as helpful.
There are tons of different fertilizers out there to use for your houseplants. However, not all of them are made equal or for the same purpose.
Our top pick is Miracle-Gro Indoor Plant Food. This liquid fertilizer is very easy to use and contains everything most plants need. You can use it on most houseplants, and it is completely safe for your family.
If you’re looking for a cheaper option, the Miracle-Gro Indoor Plant Food Spikes will save you some money in the long run. These spikes last a very long time and are very effective at keeping your plants fed.
Hopefully, one of these options works for your houseplants.
Kristin Hitchcock is passionate about an array of DIY topics - from blacksmithing to making children's toys. She understands the importance of choosing the right tool for the right job and enjoys informing others on the options currently available on the market. She is a stronger believer that you can do practically anything yourself with the right tools and knowledge.
Kristin Hitchcock
