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Indoor plant fertilizing is one of the crucial segments of basic plant care, which is why you need to get to know the essentials.
It’s much more than just pouring some nourishing liquid hoping you will get enchanting foliage and breathtaking foliage, like the one on the label. You need to know WHY and HOW it’s done.
My guide offers a spectrum of insightful information and useful tips on food for plants, so stay with me to find out more!
What Types of Fertilizers Are There?
When you walk into the store, a brick-and-mortar one or digital, doesn’t matter, you will encounter the following indoor plant fertilizer types:
- Granular (slow-release is the most common)
- Fertilizer sticks/ spikes
Each of them has its own pros and cons, but the most important is that you pick by the specific species you have. Unless otherwise stated, I wouldn’t recommend experimenting. For example, don’t use fertilizer for palms on your Dieffenbachia unless the instructions say you can.
(Think of it as mixing apples and oranges!)
Before we see the main properties of each of these categories, let’s explain one more common doubt plant food vs fertilizer.
Food is something that plants produce by themselves and that, in combination with nutrients is the process called plant fertilizing. So, even though it’s a misnomer, I shall use them synonymously just for the sake of better wording, that’s all.
Water-soluble houseplant fertilizer
This is one of the most widely implemented, simply because of its hassle-free implementation. It comes in many different forms, with the liquid being the most frequently used one. Other forms include powder, crystals, or even some sort of granules that can be dissolved in water.
How often do you use this type of indoor plant food?
There are no uniform rules, it goes anywhere between once a week, two times, or once a month. This depends on the product itself and the specific type of plant.
One of the biggest benefits of this method is that you have precise control over the frequency and the amount of food you give to your plant.
Unlike the previously described, this one gives you the freedom to enjoy laziness. Jokes aside, but once you spread this house plant fertilizer on the soil top, it dissolves slowly over a couple of months. Approximately 6 months, or even more.
Even though this method doesn’t see you actively participating every 7/15/30 days, still note down when you feed your green friends. Set a reminder so that you know when is the next time to replenish it.
As the name says, they come in the form of sticks and you simply stick them in the soil. Once you do so, your plants will start receiving food. The moment you take it out, no more food intake.
What the two above-described types of fertilizer for indoor plants have in common is that you can distribute them evenly all over the soil. With sticks, the food is concentrated on a narrower area, and there’s a possibility that food won’t reach the root system. At least not in the amount you are hoping it would.
Pro-Tip: Always choose the product which will suit your gardening habits, but what’s even more important, choose it based on your plant’s needs. Different species require different forms of food, so inform yourself on time, before you purchase the fertilizer.
Explaining the Most Crucial Nutrients in Fertilizer
When looking for the best indoor plant fertilizer, you shouldn’t just buy the first thing that LOOKS fine to you. What you need to do is analyze the amount of macro and micro-nutrients in that product.
Nitrogen (N), phosphorus (P), and potassium (K) are three crucial macro-nutrients, and they are usually expressed in bigger percentages. If those numbers are 20-20-20 or 10-10-10, then we are talking about balanced fertilizer, as the amount of each ingredient is equal.
Now, let’s discuss each of these ingredients and see why are they so important for a plant’s proper development.
This powerful nutrient serves to boost the plant’s growth. If you notice that the foliage looks somehow greener and vibrant, say thanks to nitrogen. When you purchase foliage fertilizers, make sure they have enough of this ingredient.
This ingredient reaches to the roots of a plant. By doing so it strengthens their health, which results in faster growth. It also encourages flowers to bloom. If you are an owner of flowering species, then you need food that contains a higher level of P, for example, 10 15 10 fertilizer.
The main role of this ingredient is to provide enough energy so that plants could develop well. Aside from flowering, its role is crucial in fruiting and maintaining the plant’s overall condition in a good shape. And, yes- potash is the other name for this nutrient.
As for the micro-nutrients, those should be in smaller quantities, because none of them has an as important role as macro ingredients. However, they do contribute to the overall better performance of any food. Boron, copper, chlorine, manganese, iron, cobalt, zinc are just some of them.
Pro-Tip: Even though the vast majority of species thrives well with balanced food, you should never have a general approach. Always analyze your plant’s specific needs.
To Fertilize or Not To Fertilize?
Once again, this is one of the dilemmas which has a straightforward answer. If you don’t feed the plant it won’t progress, if you do it too much, it will experience some other issues.
Okay, if you skip a day or two, or even a week, that won’t do any damage. But, if you forget to add food for a longer period, don’t be surprised if your plant slows down its progress.
As a general rule, it would be wise to add food during active development. This means from spring to fall. During winter, you shouldn’t fertilize at all. However, if you have species that produce flowers during winter, you should feed them during the entire year.
It’s important for a plant to have a rest, and that’s what winter is for. It’s not only fertilizing, but watering is less frequent during this period as well.
What happens with freshly repotted plants?
New and young plants, as well as freshly transplanted are very sensitive. This means you should be very careful with the amount of food. It’s always better to pour less than too much of it. That’s because all those nutrients could be too strong for a plant that has a delicate and yet undeveloped root system.
How often should I feed my plants?
All you should do is follow the instruction manual. This will tell you both how to dilute the product and how often your plants need feeding.
Aside from species, other conditions will have a great impact on frequency. When the plant is actively growing and/or producing flowers, you should fertilize it more often. If it is placed in low light conditions, then it won’t require as much food.
Pro-Tip: If you spot that your plant is not progressing enough, the last thing you should do is feed it MORE often or with stronger food. This will only make things worse. See if the product you have is suitable for your plant at all. If not, purchase another one as soon as you can, and create a new feeding schedule.
How to Spot Signs of Under and Over Fertilization?
As I said, it’s always wiser to add less than too much food. But either of the extremes could result in any issues- over-feeding or under-feeding.
Just like with all other basic plant care fields (temperature, lighting, watering, etc…), your plant will find some way to tell you that something’s going wrong.
Here are the signs you will spot if:
A plant is not receiving enough food
- Slower development
- Overall weaker appearance
- Reduced production of foliage and flowers
- Not enough leaves and new shoots
- Changes in leaves’ appearance, mostly in color
A plant is receiving too much food
- Slower development
- Overall weaker appearance
- No growth at all
- The lower leaves are falling
- Salt build-ups all over the uppermost layer of the soil
- Brown spots of foliage, scorched edges
If you persistently overfeed your plant, it will eventually die. But if you spot any of the signs, you will react on time, and save the day. Those build-ups I mentioned, you can get rid of them easily. Just flush the soil and take a break from fertilizing. At least two months.
The other solution is to replace the soil, and again, avoid feeding the plant for 2 months. This way you will give it enough time to rest and recover, and continue to develop properly.
Pro-Tip: You’ve adjusted the fertilizing accordingly, but still no signs of improvement? Then improper feeding is not what bothers your plant. It’s something else. Do you water it too much or too little? Are the temperature and light adequate? Check other fields to find out what’s going on with your green friend.
I truly hope my detailed guide brought you some valuable insights into plant fertilization basics. As you can see, it boils down to knowing what your plants want and need and providing it.
What’s, in your opinion, the best plant fertilizer?