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Looking for the best indoor plant fertilizers?
Fertilizers contain essential nutrients required by indoor plants, including nitrogen, potassium & phosphorus. These added nutrients aid the growth of the plant, which absorbs the nutrients through its roots.
It’s easy to overlook the importance of using indoor plant fertilizers, but indoor plants are strictly limited by the amount of soil & nutrients in the pot.
So without the ability to spread roots to surrounding soil or benefit from the nutrients naturally found in rainwater, indoor plants rely on supplemental feeding to support their growth.
Organic vs Inorganic Indoor Plant Fertilizers
Choosing the best fertilizer for your indoor plants can sometimes be a challenge. There are so many types and varieties of house plant fertilizers available, how do you know which ones are best?
Firstly, it helps to know the difference between inorganic & organic, or natural, fertilizer.
Inorganic indoor plant fertilser
If it’s manufactured, it’s an inorganic fertilizer.
This means it’s been produced artificially & contains minerals or synthetic chemicals.
Whilst these chemical nutrients are readily absorbed by plants roots, they come with environmental impacts. This includes making soil more acidic, degrading it over time.
Inorganic plant fertilizers also produce groundwater pollution, caused by excess nutrients leaching from the soil into waterways. This can harm aquatic life.
Organic indoor plant fertiliser
Organic, or natural, indoor houseplant fertilizer on the other hand, is considered the more environmentally friendly option. Organic fertilisers contain nutrients that are minimally processed & remain in their natural form.
Organic fertilisers work less quickly than inorganic plant fertilizers, because the organic matter has to decompose before it’s in a form the plant can absorb. This slower provision of nutrients ensures a steady release of nutrients into the soil containing your indoor plants.
Whether you use inorganic or organic fertiliser for your indoor plants really comes down to personal choice, both have pros & cons. But if you’re looking for the more environmentally friendly approach, opt for organic.
Benefits of Natural Indoor Plant Fertilizers
Using organic fertilizer is a gentle & safe way to feed your indoor plants, helping to:
- increase the soil’s organic matter
- improve the soil’s structure
- avoid the risk of plant burning (because the fertilizer is less concentrated)
- boost the soil’s nutrient & water-holding capacity.
Many commercial natural fertilizers are now also much more affordable (or you can make your own), plus they’re renewable, biodegradable & sustainable.
It’s best to fertilise indoor plants when they’re actively growing, but always fertilize house plants with caution & follow what the label says on commercially sold fertilizers. Used incorrectly, indoor plant fertilisers can still harm your plants.
It also pays to know your plants, so you can fertilize them in line with their specific needs.
Here are 7 organic & natural indoor plant fertilizers for eco friendly plant nutrition.
7 Natural Indoor Plant Fertilizers
1 – EarthPods Bio Organic Plant Fertilizer
Fertilizer Type: Capsules
Suitable For: Indoor & outdoor plants, potted houseplants
EarthPods organic plant fertiliser helps support & enhance robust root growth, strong stem development & leaf colour vibrancy.
A popular natural indoor plant fertilizer, EarthPods are quick & easy to use, without the mess of liquids.
Capsules break down slowly, releasing nutrients into the soil in a readily usable form. A tube of 100 pods should supply a single houseplant for 5 years.
2 – Neptune’s Harvest Organic Fish & Seaweed Plant Fertilizer
Fertilizer Type: Liquid
Suitable For: Indoor & outdoor plants, potted houseplants
If you don’t mind a slight fishy smell, Neptune’s Fish & Seaweed fertilizer is a popular organic choice.
Suitable as an indoor plant fertilizer, Neptune is a popular multi purpose fertilizer that will help houseplants grow stronger, produce more flowers & last longer.
Gentle & effective, it’s easy to mix & apply by hand or sprayer.
3 – Joyful Dirt Organic House Plant Fertilizer
Fertilizer Type: Granules
Suitable For: Indoor house plants
Joyful Dirt’s organic house plant plant fertilizer is specifically formulated for indoor plants.
To use, simply shake some organic based fertilizer onto the soil on either side of your house plant & water as usual.
The plant fertilizer contains Mycorrhizae & other nutrients to help houseplants thrive, using less water.
4 – MARPHYL Organic Liquid Fertilizer
Fertilizer Type: Liquid
Suitable For: Indoor & outdoor plants
MARPHYL Organic Liquid Soil Enhancer is packed with nutrients, vitamins & minerals from marine micro algae.
Naturally high in nitrogen, phosphorus & potassium, MARPHYLL organic plant fertilizer naturally boosts plant health by replenishing the soil as plants grow. Suitable for indoor & outdoor use.
100% natural, organic, vegan, eco-friendly & non GMO.
5 – Aquatic Arts Indoor Plant Fertilizer
Fertilizer Type: Liquid/granules
Suitable For: Indoor & outdoor plants
Whether you have pots, holders or hangers, Aquatic Arts Indoor Plant Fertilizer is designed to promote house plant health & prevent wilting.
Gentle & non-burning, this indoor plant fertilizer also helps reduce brown spots & yellowing of leaves.
Containing 100% natural ingredients, an 8 oz typically lasts 6 months to a year. To use, mix 1 tsp of fertilizer with 2 cups of water.
6 – EarthPods Bamboo + Bonsai Indoor Plant Fertilizer
Fertilizer Type: Capsules
Suitable For: Indoor bamboo & bonsai house plants
EarthPods organic indoor plant fertilizer is specially formulated for indoor bamboo & bonsai plants.
To use, simply push 1 capsule into the centre of the soil around your plant or open & sprinkle if your plant is growing in bark or pebble substrate.
Containing a variety of organic plant nutrients, trace minerals, soil life & humates in a form readily available to your plants, EarthPods are eco friendly & simple to use.
7 – Homemade Indoor Plant Fertilizers
If you’d prefer not to use a commercial indoor plant fertilizer at all, there are also a number of household waste items you can use.
Crushed egg shells help lower acidity & add calcium, used coffee grounds add nitrogen & banana peel boosts potassium. Not only are these options completely natural, they also won’t cost you a penny.
You can also use green tea or molasses. Here’s a guide on how to use these items as indoor plant fertilizers.

Indoor Plant Fertilizers – Conclusion
If you’re looking for the best indoor plant fertilizers, there’s lots of choice available. Organic & natural indoor plant fertilizers are the eco friendly choice over inorganic, artificially produced ones.
Always follow the instructions on a commercially bought fertilizer & get to know your indoor house plants, so you know how much fertilizer to use and when to use it. If you’re not sure about the amount needed, this is where natural & organic slow release fertilizers are a good choice, as they’ll give your plant time to absorb the nutrients.
Online reviews are a also often a good indication of how well a fertilizer performs on indoor house plants.
And if you want to go completely natural, consider making your own natural indoor plant fertilizer with coffee grounds, banana skins or crushed eggs shells.