If you’re an aspiring houseplant parent who has killed plant after plant in an attempt to liven up your indoor space, you’re not alone. And you’re probably frustrated. After tossing out your latest indoor gardening casualty, you might be throwing up your hands and asking yourself, “What does a plant need to survive and grow, anyway? Magic?”
First, cut yourself some slack. Not everyone is born with a green thumb. (In fact, most people aren’t.)
Keeping plants alive isn’t intuitive for a lot of us, but the good news is that gardening is a very learnable skill. Once you develop a basic understanding of how plants work and how to replicate their preferred environment indoors (and which plants work best for your space), you’ll find you’ll have a much easier time keeping plants alive, and you finally live out your indoor jungle dreams!
In this article, we’ll go through the most important elements of plant care so you can understand what a plant truly needs to grow and thrive.
Plant Light Requirements
One of the most important parts of caring for a plant is ensuring that it has the proper lighting conditions. After all, light is where plants get their energy through the process of photosynthesis, so without light (and enough light), plants can’t survive.
We might think the light in our homes is bright, but remember, plants grow outside (obviously, but hear us out). Even the brightest indoor light rarely compares to lighting conditions outside, so “bright” indoor light might not be enough for some plants.
It’s a good idea to assess your indoor lighting conditions so you can know which plants would thrive in your space. An easy way to do this is with a light meter. (We like this 3-in-1 meter that also measures soil moisture content and pH level.)
Another important factor is to understand the different lighting terms you’ll see on plant labels and care guides, and what this looks like in your home.
Here are the most common terms you’ll see:
Bright, indirect sunlight
This means that the plant likes very bright sunlight, but doesn’t want the sun’s rays to shine directly on its leaves. This usually requires an east-facing window where the plant will get plenty of bright light throughout the day, but no direct light (except maybe a little morning sun, which is fine).
The vast majority of tropical houseplants you’ll see in stores and online fall into this category, so get really familiar with what this looks like! (And if you’re looking for a home and plan to get a lot of plants, look for lots of east-facing windows!)
A room with lots of windows would also work well, even if they don’t face east. Just watch out for the hot midday or afternoon sun shining directly on your plant’s leaves.
This means the plant should be placed directly in the sun’s path. Indoors, this usually means a south-facing window, but some plants might also do well outside if the temperatures and humidity are favorable.
This means a plant prefers a north-facing window, or to be placed deeper in a room with a window. Avoid allowing any direct sunlight on the plant, even morning sun.
These plants don’t need a lot of light, so you can place them deeper in any room with a window. Definitely avoid direct sunlight!
Plant Watering and Humidity
Another aspect of plant care that’s easy to get wrong is watering and humidity. Let’s start with watering, because this is usually what people think of when they think of plant care.
Watering is considered to be one of the trickiest parts of plant care because most people tend to over- or underwater plants. A lot of factors also affect how much water a plant needs to be healthy at different times of the year and in different conditions.
Factors like lighting conditions, temperature, time of year, and soil composition can all affect how efficiently plants use water, so it’s best to check your plant’s soil frequently so you know when it’s ready for a drink.
We suggest using a moisture meter so you can understand what’s going on deeper inside the root ball, because it’s possible for the surface of the soil to be dry while the root ball is actually soaked!
You’ll also need to know how to interpret plant care labels and what different watering terms mean.
Plants typically fall into three different watering categories: light, medium, and heavy. These are often indicated by little raindrop icons on plant labels, though there might be variation.
Typically, light waterers or drought-resistant plants should be watered when the soil dries out. (But don’t let it stay completely dry for too long.) There’s a bit of wiggle room here, though. Desert plants like cactuses and succulents like to dry out all the way, while dracaenas and pothos plants should be watered when the top half of the soil is dry, but they’re all considered light waterers. Expect to water these plants every 10-21 days.
Medium waterers do best when you water them when the top 2-3 inches feel dry to the touch, or when a moisture meter reads 3-4. Most tropical plants will fall into this category. You’ll need to water these plants about every 7-14 days.
Heavy waterers need to be watered frequently, when the top inch or two of soil feels dry. Ferns (especially the notoriously fussy maidenhair fern) usually fall into this category. Sometimes these plants must be watered several times every week or even every day!
When it’s time to water, it’s best to add water to the top of the soil until it just starts to drain out the bottom of the pot (it’s also critical to use a pot with drainage holes, by the way). Then allow the plant to drain completely or empty the drainage trays right away, because most plants don’t like to sit in water!
Bottom watering is also an option, especially for habitual overwaterers! Here’s how to do this.
Humidity is also important, especially for rainforest plants with delicate leaves. If conditions are too dry, leaves can dry out or develop unsightly brown spots, even if you’re giving it enough water.
While desert plants like succulents do just fine in dry conditions, most houseplants hail from the tropics and do best in humidity levels around 40-50%. Some moisture-loving plants like ferns like even more humidity and do best in a steamy bathroom, or need their own personal humidifier to keep humidity levels up.
In general, grouping plants or using a humidifier will create enough humidity to keep leaves soft and supple.
Nutrients for Plants
This is an often overlooked area of plant care that we can’t stress enough!
While plants get their energy from sunlight, they get their nutrients from the soil they grow in. This isn’t usually an issue in the wild because in nature, the soil gets a constant supply of new nutrients as plant and animal material breaks down into the soil. But a potted plant only has access to the soil in its pot and can use up all the available nutrients in just a few months.
This means you’ll need to supplement with fertilizer. You can purchase this in pellet or slow-release form, or as a liquid that you add to your plant’s water. Different plants need different amounts of nutrients, so it’s important to find the right balance for your plant.
The balance of major nutrients in a fertilizer is expressed as a three-digit number, or NPK ratio. This stands for nitrogen, phosphorus, and potassium, three of the major nutrients plants need to grow.
Plants need these nutrients to grow healthy new leaves, stems, and roots. When your plant develops nutrients deficiencies, you might notice yellowing or browning leaves, flimsy stems, wilting, and stunted growth.
Nitrogen is essential for cell formation and chlorophyll production. This helps your plant build sturdy stems and overall strong structure.
This mineral is crucial for building robust root systems, producing seeds, and boosting immunity to pests and disease. Phosphorus is also a key for your plant’s metabolism.
Also important for growing strong roots and healthy seeds, potassium also affects water regulation and the absorption of other minerals.
Benefits of Minerals for Plants
Plants need minerals for the same reason we do: to support bodily functions like growth, metabolism, respiration, and water and nutrient absorption. Without these functions, the plant will die.
How Often Do Plants Need Nutrients?
How often should you fertilize your houseplants?
This, of course, depends on the type of plant (again, a quick Google search goes a long way here) and the type of fertilizer you use. A slow-release or pellet fertilizer will need to be applied less often than a liquid fertilizer.
Plants will also need to be fertilized more often during the growing season (usually spring and summer) when they’re actively building new tissues.
This does get confusing, because there’s no perfect answer here. (Luckily, if you accidentally over-fertilize your plant, there are simple ways to reverse the problem. And if you under-fertilize, you can always add more!)
A lot of houseplant parents (us included) have trouble remembering a fertilization schedule, so that’s why we created Indoor Plant Food. This liquid fertilizer is the ideal NPK ratio for almost all indoor plants (succulents excluded) and is gentle enough to be applied with each watering. No schedule needed! Just mix a little into your watering can every time you water, and you’ll be good to go. If you’d like, ease up in the fall and winter when your plants might be dormant, but you can keep using Indoor Plant Food year-round to support your plant’s health and growth.
You might think that all plants have to grow in soil, but that’s actually not true at all! Growing substrate is the material in which your plant’s roots live. This could be potting mix or a hydroponic or semi-hydroponic medium like LECA or even water. There are pros and cons to every growth medium, so it’s worth exploring different options to see what you like best.
Do Plants Need Soil to Grow?
It’s hard to get away from the idea of soil as a growth medium. Think of it this way: Plants need support for their root systems so they don’t fall over, they need nutrients, and they need to be able to absorb water. Potting soil can provide all those things, but soil isn’t the only way to meet a plant’s needs.
As long as you give your plant the right amount of fertilizer and nutrients, a sterile growing substrate can actually be a great choice because it carries less risk of infection.
It’s also possible to grow some plants in water alone (this method is called hydroponics). As long as the plant has a steady supply of clean water and nutrients, and some way to stay upright (like support from the neck of a vase), the plant won’t need soil at all, and this method can actually reduce the risk of over- and underwatering because the roots will only absorb as much as they need.
If you have trouble with watering and infections like root rot, you might want to look into these hydroponic or semi-hydroponic growing methods!
What Is the Best Soil Mix for Houseplants?
This might leave you wondering…what is the best soil mix for houseplants, anyway?
Again, this depends on the type of plant. Some plants prefer a chunkier, sandier mix that drains very quickly while others like a rich, peaty mixture that hangs on to a bit more moisture.
However, we find that a good all-purpose mix for most tropical houseplants like aroids is our Premium Monstera Potting Mix. We’ve potted all kinds of plants in it, and they do great!
Know Your Houseplants
Every plant needs something different, so the best way to care for any plant is to get familiar with the basics that every plant needs, understand common terms you’ll find on labels and in care guides, and then do a little research to see what will help your particular plant thrive.
The better you get at recreating a plant’s natural environment, the healthier your plants will be!