Calatheas are beautiful houseplants known for their lush foliage and robust growth. They can grow up to three feet in height when properly cared for!
There are seemingly endless varieties, and they make their way into most indoor gardens at one point or another.
But with picky growing requirements, calathea can go from thriving to barely surviving very quickly. They’re finicky plants with a lot of personality!
So, how do you keep your calathea from keeling over? Aside from paying strict attention to their growing requirements, the best way to keep a calathea happy is to fertilize it.
Fertilizing all your houseplants, even the hardy pothos, is a good idea. But for plants like calathea, which can suffer from root rot and even fungal leaf spots–it’s the key to happy and healthy growth.
In this guide, I’ll go over my top 5 best fertilizers for calathea. To keep your houseplants happy, I’ve also thrown in some growing tips and tricks. On this list, you’ll also see my favorite organic calathea fertilizer, the best budget-friendly pick, and more!
In a hurry? No worries! Here is a quick snapshot of my top 5 fertilizers for calathea. Keep reading to learn more about my top pick fertilizers for calathea!
Best Overall: Bless Your Soil Indoor Houseplant Food
The Bless Your Soil Indoor Houseplant Food is my top pick for calathea thanks to its robust list of micronutrients, and easy-to-use powder formula!
The micronutrients in this product are derived from sea kelp. The list boasts magnesium, copper, zinc, and more! All of them are formulated to help your calathea thrive.
The 12-4-8 NPK ratio is quite strong, making this a good product for mature calathea plants. It’s extremely good for calatheas that have become nutrient-deficient in their pots.
1 pound of this fertilizer has over 200 uses, making it well worth the investment for your calathea. The powder formula is also easy to use and odor-free.
The directions do say to use this product with every water, but I’d recommend starting with every other or even every third watering. You can always add more once you realize your calathea likes this fertilizer (because it will!)
If this plant food doesn’t sound like your cup of tea, though, there are four more amazing options to choose from on this list.
Why Do You Need a High Quality Fertilizer For Calathea?
Calatheas are houseplants that don’t fruit, and rarely flower. You might be wondering–why bother fertilizing them at all?
Well, there are a few good reasons to fertilize your calathea. Simply put, it’s the best way to keep your calathea happy and healthy, and here are a few reasons why.
Root Rot
Root rot is extremely common in potted plants, especially ones like calathea that like a lot of water (I’ve noticed that monstera deliciosa are extremely prone to root rot, as well).
Root rot is characterized by slimy, rotten roots, as well as yellowing leaves and stunted growth. You’ll notice your calathea’s stalks slumping over, and potentially even some brown spots on both the stalks and leaves.
Root rot is caused by fungi in the soil that thrive when the soil is overly wet. They can also prey on already weak or ill plants since they’re more susceptible to disease.
Fertilizers with a high dose of potassium (aka potash) can help to combat root rot. Potassium helps plants to ward off diseases and keep themselves healthy. It won’t cure your overwatering problem, but it can help a sick calathea recover to fight off root-rot-causing fungi.
When looking for a good calathea fertilizer, I like to pick one that’s high in potassium for this very reason. I’ve dealt with root rot before and it’s no joke!
Calathea’s Natural Growing Environment
Calatheas are tropical by nature, hailing from the tropical Americas, which means they have very unique and strict growing requirements. Like palm trees, they aren’t used to growing in an indoor environment.
They enjoy bright yet indirect light, mimicking their natural habitat on the rainforest floor. It’s actually occasionally called the ‘shadow plant’ for this reason.
Due to their tropical nature, calatheas also love high humidity. This can be difficult to obtain if your calathea lives indoors, especially if you live in a dry climate.
Fertilizing your calathea can support it when some of its growing requirements are unable to be met. While a high-quality fertilizer can’t replace humidity or proper lighting, it can provide some additional nutrients to keep your plant happy.
Nutrient Depletion
Nutrient depletion for potted plants is very common. Essentially, the plant saps up all the nutrients it needs out of the soil it’s potted in, and then has nothing left to use.
Repotting your calathea might be a regular thing, especially because they can grow up to three feet tall. Here’s a tutorial on how to properly repot one:
If you notice your calathea doesn’t perk up after repotting, then adding a dose of high-quality fertilizer should do the trick.
Adding those extra nutrients to the soil is key for keeping your calathea happy and healthy!
What to Consider When Choosing The Best Fertilizer For Calathea?
Calatheas can definitely benefit from high-quality fertilizer. But what should you be looking for when choosing the best fertilizer for your beloved plant?
NPK Ratio
All fertilizers have a sequence of numbers that look like this: 10-10-10.
The first number stands for nitrogen content. Nitrogen helps plants with green, leafy growth. Since calatheas are green, leafy plants, this number is typically the highest.
The second number represents phosphorus, which helps plants to bloom and grow a stronger root system. This is essential for calatheas that can fall victim to root rot, as discussed previously.
The last number stands for potassium (aka potash). This component helps plants remain overall healthy, which is also very helpful in preventing diseases from harming your calathea.
Organic Versus Inorganic Fertilizers
Whether you decide to use organic or inorganic products is entirely up to you–we often recommend a mixture of both.
Organic products are, simply put, made of organic materials. They are typically gentler on your plant and better for the environment, being comprised of all-natural ingredients. However, they can be more expensive and tend to have components that are comprised of animal parts such as bone or blood meal. This makes them inaccessible for vegans (if your veganism extends to your garden).
Inorganic products can be harsher, but when used properly, they work wonders. They’re also typically cheaper and easier to find in your local home and garden store. The key to using an inorganic product is to read the directions thoroughly and never over-apply, especially to a delicate plant like a calathea.
This list of the best fertilizers for calathea contains both organic and inorganic products so that you can use whichever one is best for you and your garden.
Is The Product Pet-and-Kid Safe?
If you have pets and kids at home, I recommend using a product that is explicitly non-toxic for indoor plants.
Animals (and children) can be quite nosy, and I find it best to err on the side of caution when choosing a fertilizer that could be in reach for them.
Several of the products listed here are explicitly safe for pets and kids, however, that doesn’t mean that it’s good for them to eat! Even “safe” products can be harmful if a large amount is ingested.
Some houseplants are, in and of themselves, toxic. Luckily, calathea is not one of them! If you have pets and kids that have a tendency to get into things, I recommend keeping a non-toxic fertilizer in your home (but still out of reach!).
My Reviews of the Best Fertilizers for Calathea
Bless Your Soil Indoor Houseplant Food
This easy-to-use powder fertilizer is my favorite for calathea and for good reason!
The micronutrients in this product are derived from sea kelp and can give your nutrient-deficient calathea the boost it needs. It’s also designed to promote overall plant health with an NPK ratio of 12-4-8.
This fertilizer is, essentially, a multivitamin for your calathea.
The NPK ratio is pretty strong, so use this sparingly with a younger plant. The directions also say to use it every watering–I’d caution against that. Try every other watering at first to see how your calathea likes this product. You can always add more!
Pros
Easy-to-use powder formula
Packed with micronutrients derived from sea kelp
Designed to promote overall plant health
Cons
12-4-8 NPK ratio might overwhelm young or sick calathea plants
Directions say to use it during every watering
Jobe’s Houseplant Fertilizer Spikes
When it comes to convenient fertilizing, there’s nothing better than a fertilizer spike! Not only are these Jobe’s Houseplant Fertilizer Spikes easy to use, they’re also extremely budget-friendly.
They’re designed to feed your calathea right at the roots, and the slow-release system won’t overwhelm your plant, but rather keep it sustained for a long while.
Each fertilizer spike costs mere cents and can fertilize your calathea for weeks at a time.
The 13-4-5 NPK ratio is pretty strong, so this product is best suited for mature calatheas that really need the boost. And because of the pre-measured nature of fertilizer spikes, it’s difficult to tailor the dose to your plant’s specific needs.
Pros
Designed to feed right at the roots
Amazing value for a long-lasting product
One of the most convenient types of fertilizer on the market
Cons
13-4-5 NPK ratio can be too harsh on some calathea
Can’t tailor the dose to your plant’s specific needs
Espoma Organic Indoor Houseplant Food
My top organic pick is definitely this indoor houseplant food from Espoma! Their products are high-quality and affordable, which I’m a huge fan of.
For your calathea, this liquid fertilizer boasts a 2-2-2 NPK ratio, which is gentle while still being effective. It’s extremely easy to dilute in a watering can and apply to your plant, too.
This product is also safe for pets and kids, which gives plenty of gardeners peace of mind!
And, of course, Espoma is committed to sustainability, using 25% recycled materials and 100% solar power in all of their facilities. Go, planet Earth!
However, the NPK ratio could be too gentle for a robust calathea. It should also be noted that this isn’t a vegan product, since it does contain “hydrolyzed fish protein and bone meal.”
Pros
Gentle 2-2-2 NPK ratio won’t overwhelm your calathea
Safe for pets and kids
Company is committed to sustainability and organic products
Cons
NPK ratio could be too gentle for mature calathea
Not a vegan product
Joyful Dirt Houseplant Fertilizer
Joyful Dirt is one of my favorite brands for houseplant fertilizer, namely because of their convenient shaker bottle. All you have to do is add a few shakes of this granular fertilizer to the soil around your calathea, mix it in a bit, and boom! You’ve got a fertilized plant.
You can also use this 3-1-2 fertilizer in a watering can if you prefer.
This fertilizer is OMRI Certified Organic, and the mycorrhizae fungi in the formula are designed to promote healthy root growth.
My only qualm with this fertilizer is that it’s pretty expensive. Definitely a “treat your plant” kind of product!
Pros
Convenient shaker bottle
OMRI Certified Organic
Can be used as a granular or water-based product
Cons
Expensive
Very concentrated=easy to over-use
I love this water-soluble plant food for a young calathea because of its well-rounded 4-3-4 NPK ratio. It’s designed to promote root health, robust leaf growth, and even flowering.
This concentrated product makes up to 12 gallons of treated water, so it’s worth the investment for your calathea!
It also isn’t stinky, which is good for indoor plants. Some products can have a distinct odor to them, but not this one!
However, there have been reports of mold on the soil of some plants as a result of this product. Keep an eye on your calathea and if you see any, be sure to switch out your soil.
Pros
Makes up to 12 gallons of fertilized water
No odor
Well-rounded NPK ratio of 4-3-4
Cons
Some people report mold growth
Best Overall: Bless Your Soil Indoor Houseplant Food
While these are all amazing products, the Bless Your Soil Indoor Houseplant Food is definitely my favorite for calathea. I love the strong NPK ratio of 12-4-8, as well as the easy-to-use powder formula.
The micronutrients are what truly sell this product, though. Derived from sea kelp, the formula is designed to help your houseplant thrive. Nutrient-deficient calathea will definitely thank you for this one!
If this isn’t the product for you, however, there are four more amazing options here to choose from. No matter what, as long as you properly use a high-quality fertilizer, your calathea should thrive.
Final Thoughts On The Top 5 Fertilizers For Calathea
Calatheas are beautiful, robust houseplants that can thrive when given the chance. They’re picky about their growing requirements, being native to the rainforests of the tropical Americas and therefore used to high humidity and low light.
But a healthy dose of high-quality fertilizer can help your calathea to thrive. Any of the options on this list of the top 5 fertilizers for calathea are sure to help your houseplant grow happy and healthy!
I hope this guide to the top 5 fertilizers for calathea was helpful for you. Stay happy, stay healthy, and stay planting!
FAQ
Are Calatheas Toxic to Cats?
Calatheas are non-toxic to cats, dogs, and humans. They are not a food source and therefore do not have any nutritional value, but they also will not cause any harm.
Why is My Calathea Drooping?
Calatheas droop because of either too much or too little water. Check the soil to see if it’s moist–if so, let it dry out and see if your plant perks up. If not, water your calathea and see if that helps.
How Often to Water Calathea?
Calatheas enjoy deep weekly watering. In the winter, water your calathea less often to prevent root rot or drowning it.
Why is My Calathea Browning?
Calathea leaves brown as a sign of under-watering. Be sure to deeply water your calathea at least once a week.
Should I Cut Off Brown Calathea Leaves?
Yes. Brown and dying calathea leaves can no longer provide energy to the rest of the plant, and should be pruned so your calathea can focus its energy on the healthier leaves.