We are now past the half-way point in our Indoor Plants for Beginners series! So far, we have talked about how to find healthy plants for your home, how to properly water the plants you have adopted, and how to choose the proper soil for your plant’s species. This week, we decided to cover a widely debated topic that has caused more confusion through the misinformation in many internet articles than any other subject: fertilizer. While one third of the plant parents out there believe you don’t need to fertilize because your plants are indoors, another third believes you should give your plants fertilizer all the time all year because it helps everything grow faster; the other third is just plain confused, and we don’t blame them.
Before we entered the plant world, we regarded this subject as the most difficult to understand because of all the conflicting information available in gardening publications and indoor plant articles. In this installment, we are going to set the record straight once and for all and cover all the different aspects involved with fertilizing your indoor plants, including the why, what, how, and when. Once you understand the fundamentals of feeding your plants, you will be able to grow anything all year round.
This is Indoor Plants for Beginners, Part Four: How to Fertilize & How Often!
Why do you need to fertilize your indoor plants?
Yes, you absolutely do. Just because a plant is growing indoors does not mean that they don’t need the same nutrients and vitamins that a plant living outside expects. Unlike a garden that can provide a near endless supply of food because of the worms and microorganisms living in the soil, an indoor plant needs you to intervene and feed it since it can’t provide that for itself. Plants rely on sunlight, oxygen, water, and nutrients as their food, so if it doesn’t have access to each piece of the puzzle, it can grow weak and leggy or it may not grow at all. When you properly fertilize your houseplants, you are giving them the ability to grow larger and stronger and even produce baby plants as a thank you.
When would you want to fertilize a houseplant?
This is the tricky part, because there is no one-size-fits-all solution for fertilizing houseplants because of the different needs of its species. However, there are two rules you should know to build your fertilizing foundation on:
1. The faster a plant is growing, the more often you are going to want to fertilize, and
2. depending upon where you live, you may need to stop fertilizing your plants in the Wintertime.
The first thing to consider is the species of the plant you are going to fertilize. There are plants like the Pothos and Spider Plant that can put out new growth very quickly and very often when given the proper conditions. However, growing at this rate requires a lot of energy on the plant’s part, which they get from the sunlight they receive, but also from the nutrients in their soil. The faster a plant grows, the faster it is going to soak up all the food in the soil, so it’s a great practice to fertilize plants like this often. On the other hand, plants that grow at a slower pace do not need to be fed as often. Monitor your plants’ growth for a few months to form a fertilization schedule that fits their needs.
Aside from the plant itself, you should also consider the seasons when fertilizing. You may be thinking “but my plants are indoors – how can they be affected by the weather outside?” Well, even with being inside, houseplants are still seeing the same decrease in temperature and daylight as anything outdoors would, just to a less extreme degree. It is not uncommon for indoor plants to go into a period of dormancy in the Winter; during this time, a plant’s rate of growth may slow down or stop completely. Because the plant is now focused on conserving its energy, it’s not necessary to feed it again until Spring returns and your plants come out of “hibernation.” It is important to note that if you live in a location that does not experience extreme seasonal changes or even frost for extended periods of time, you can disregard this and fertilize all year round.
There are so many different kinds of fertilizer, so what should you use?
Whether you shop online or in a store, the variety in fertilizers can be overwhelming. There are not only so many different kinds of fertilizers, but the ingredients used in them can vary greatly, too. To make it simple, we recommend the use of four different kinds of fertilizing agents:
4. and Organic Matter
Slow-Release was given a very straight-forward name describing exactly how it works: the actual fertilizer is a sold that is coated in a shell that breaks down over time, slowly releasing the fertilizer and its nutrients into the soil. This is popular in the indoor plant community because it doesn’t require adding extra fertilizer throughout the season – you mix your slow-release into your soil once at the beginning of the season and let it sit for months at a time.
Granular fertilizer is similar to Slow-Release only in that it has a coating to separate the nutrients inside from the soil. However, once water is added to the plant, the granules release all of its fertilizer right away, which can potentially lead to nutrient shock if you aren’t careful.
Liquid Fertilizer is just that, fertilizer in a liquid form. This has also become quite popular with the rise of houseplants in the world for its convenience factor: add a certain amount to create a solution and water as usual – it’s as easy as that.
Last but not least, we have what we call “Organic Matter.” This name can be misleading because all the previous fertilizers we listed can be made of organic materials, too; however, what we will call organic matter can be defined as materials that are completely natural in creation and ingredients. Things like compost and worm castings can be included in this group. Regardless of the plant species, you can use anything we listed here because the type of fertilizer doesn’t matter as much as your proper use of it.
When you are ready, this is how to fertilize your plants.
Just like the multitude of methods you can use to water your plants, there are many different ways you can fertilize them, as well. How you fertilize your plants will depend upon the type of fertilizer you are using, but mixing the fertilizer directly in the soil, topdressing the soil, or making it water-soluble are the three main methods you will most frequently use. Also, just because you may decide to top-dress your plant once does not mean you have to stick to that – you can change up your routine however you see fit to care for your plants.
When you use a granular or slow-release fertilizer, you are most likely going to want to mix the little, pebble-like pieces into the soil directly. If you do this to repot a plant, you can ensure an even distribution of fertilizer which will only keep the soil healthy. Top-dressing your soil is the act of spreading your fertilizer directly on top of the soil so that as you water it, the nutrients soak into the soil from the top down. Certain organic matter fertilizers like worm castings do well with this method because they look identical to soil and will mix with the substrate over time anyway. Last is the watering method; this can be done with a liquid fertilizer, diluted in the water, or through steeping organic matter (yes, like you would steep a tea bag) in a cheese cloth or similar bag to release all its nutrients. It’s up to you which method you use!
Here are the signs to look for with fertilizing.
One of the wonderful things about getting to know your plants, is that there are multiple ways a plant can communicate to you that it either needs to be fed or it has been fed too much. Certain signs like yellowing edges on leaves, strange, discolored spots, veins fading in color, and white stripes on the leaves can be a red flag for a nutrient deficiency of some kind. If you are confident that you are neither over or under watering your plant, and that it receives all the oxygen and sunlight it needs, then you may need to fertilize your plant. Add your fertilizer of choice and monitor how your plant reacts; who knows – it could save your plant’s life!
Bonus: this is how to fertilize your indoor plants when they are in self-watering containers.
Just because you have something potted in a self-watering planter does not mean it is more difficult to fertilizer them; in fact, it may be even easier to feed your houseplants in a container like this! The chamber that it used to store water can now be used to supply a water-soluble fertilizer solution to a plant at its own pace.
As we mentioned before, there are certain kinds of fertilizers that can be dissolved or steeped in water to release their nutrients and vitamins. When a solution like this is created, you can add it to the tank of a self-watering container instead of plain water. As time goes on, you can refill the tank with regular water to dilute your solution until it has been completely absorbed. There’s no need to top dress your soil with fertilizer or do anything else messy to feed your plants with a container that does the work for you.
And that is the fourth installment of our six-part Indoor Plants for Beginners series – and we could not be more excited to have you on this journey with us! Keep an eye out two weeks from now for our next guide, full of tips and tricks on how to be the best plant parent you can be.
Don’t forget to check out our other blogs! We offer tips and tricks to get the most of your gardening or indoor plant journey on a regular basis. Do you have a subject you would like us to write about? Let us know in the comments below!