Indoor Plant Temperature & Humidity Needs

I remember the first time I tried caring for a houseplant. It died soon after.

Granted, I was busy and didn’t look after it much. But, knowing what I know now, I probably wouldn’t have done much better then.

That said, I didn’t let my early failures stop me. Although, they did teach me to be cautious. As such, my first few successful tries were with succulents that could pretty much leave on their own.

But, that was enough to give me confidence to try other plants.

If you’re where I was before, intimidated or unsure about how to grow your own houseplants, this guide is for you.

By the end, you’ll know how to care for  indoor plants, including how to water, prune and even propagate them.

While it’s a lot, I’m sure it will be worth your while when you have your own lovely indoor garden.

 

What is a Houseplant?

A houseplant is a plant that’s grown indoors. You take care of it like you would the plants in your garden. But, the biggest difference is that being indoors, the conditions the plants experience change.

Outside, they receive a lot of sunlight. That’s not the case in your home.

Similarly, outdoor plants are susceptible to different seasons. Among which, winter being the most treacherous. Houseplants don’t have to worry about drastic climate changes because of your home’s thermostat control.

 

Most Houseplants are Tropical Plants

One of the things not many people realize is the majority of houseplants are tropical plants.

That said, the converse isn’t true: not all tropical plants are houseplants.

To define, tropical plants are plants that have their origins in tropics. That is the area of the Earth that’s just above and below the equator.

As such, these plants are used to tropical climates, which is:

  • Hot
  • Humid
  • No snow, frost or winter
  • Temperatures that are 65 degrees Fahrenheit and higher
  • Similar sunny climate all year round
  • About 10-15 hours of sunlight daily

Does that remind you of somewhere?

Yes, your home.

That’s why tropical plants make perfect houseplants. We control the environment inside our homes to make them toasty, in part also to make it more livable than the outdoors especially during the harsh summer and frosty winter times.

 

There are Some Sub Tropical Plants As Well

In addition to the tropical plants, there are a handful of subtropical plants that are popular houseplants as well.

Subtropical means just beside the tropics. As such, these are the areas right above and below the tropic region right before the Arctic (from above) and Antarctica (from below).

 

How Long Do Indoor Plants Live?

Here’s a strange, albeit very practical question I get a lot. How long do houseplants live?

Since you’re going to invest your time and effort on them, you might as well know what you’re getting in return, right?

That way, you can plan ahead. And, when the time comes, be prepared to replace them.

On average, it’s about 2 to 5 years.

But, just as there are a few houseplants that only stay around for a couple of years, there are also those that live over 10 years. And, there are those that span decades to the point where you’ll be passing them onto your kids.

The good news is, except for a few of them, it’s fairly easy to propagate your plants. This means you’ll be able to grow new plants from them without having to start from seed again or buy them from the garden center.

If you do so, you’ll be able to enjoy your favorite houseplants indefinitely.

 

Temperature

Most houseplants are tropical by nature. As such, they’re happiest in moderately warm environments. This runs between 70-80 degrees during the daytime.

And, because they’re used to being outdoors where night-time temperatures dip, they’ll enjoy it when the temperature stays at around 65-70 degrees in the evenings.

That said, plants are very adaptable.

So, over time they’ll find a way to get acclimated to your home’s environment. As long as it doesn’t get overly cold or hot, they’ll survive.

It’s likewise important to be aware that different plants prefer different temperatures. So, it’s a good idea to set your thermostat to one that suits you and your plants.

Or, you can likewise choose plants that are best suited for the temperature of your home.

Below is a chart of the different cool temperature, medium temperature and warm temperature houseplants you can grow.

This will help you decide what kind of indoor plants to grow depending on where you live and how hot the summers get and how cold the winters get.

chart of temperature requirements for indoor plants (list of cool and warm weather houseplants)
chart of temperature requirements for indoor plants (list of cool and warm weather houseplants)

 

How Does Temperature Affect Your Plant’s Growth?

Before moving to the next section, there’s one other thing that’s worth knowing.

This is your home’s temperature affects many other aspects of plant growth, among which are their rate of photosynthesis and respiration. It also affects how quickly the water your give it evaporates.

Photosynthesis is the process where plants use light, water and carbon dioxide to produce sugars and starch. Respiration then breaks down these sugars to create energy.

High temperature increases the rate of respiration.

And, if your plant isn’t producing enough starch and sugar to meet its demand, it will use up most if not all the sugar stores. This leaves little to none for growth.

As a result, your plants don’t grow as they normally would.

If this continues and your plant doesn’t get enough light to increase its production of sugars, it eventually dies.

So, it’s important to balance temperature with light.

This is especially true when the seasons change, particularly during the summer and winter. In both cases, light and temperature experience significant changes.

The chart below shows you what happens to your plant’s functions when temperature goes up or down.

This includes the effects of temperature on photosynthesis, transpiration, respiration,  dormancy, flowering and sugar stores.

chart that shows you the effects of temperature on plant functions & processes (photosynthesis, respiration, transpiration, flowering, dormancy and sugar storage)
chart that shows you the effects of temperature on plant functions & processes (photosynthesis, respiration, transpiration, flowering, dormancy and sugar storage)

 

Related

 

Humidity

Humidity is the amount of moisture in the air. How much or how little humidity there is in the air affects all living things.

For example, if humidity is high, that means the air is saturated (filled) with moisture. Because it can’t take a lot more water, your body’s sweat won’t evaporate as quickly as it normally does.

This is why high humidity causes you to feel hotter. You’re unable to sweat which is your body’s cooling mechanism.

In contrast, lower humidity makes you feel cooler, in part because it allows your body to sweat.

 

Do Houseplants Like Humidity?

Most common houseplants trace their origins in the tropics or forests. As such, they thrive in humid environments.

Unfortunately, most homes have much lower humidity levels. In part, it’s because you’re running the heater during the winter and fall. And, operating the air conditioning in the summer.

Both make the air drier than what most houseplants would want.

To give you an idea, the ideal home humidity is around 30-50%. But, you’ll find some homes going down to as low as 20%.

In contrast, many houseplants thrive when humidity levels hover between 40-60%. Some plants enjoy even up to 80 percent.

 

How Does Humidity Affect Plants?

Plants react somewhat similarly to how you and I do with low humidity. It causes them to lose more moisture.

But, the difference is they do it through transpiration while we do it via perspiration.

More importantly, while you’re able to drink more water, that’s not always the case for your plants. There may not be enough water in the soil for them to absorb.

As a result, they can start wilting, their leaves may curl, and they won’t grow as they normally would.

Similarly, humidity levels also affect the rate of photosynthesis in plants. But this time, it’s the opposite.

While low humidity increases transpiration, it decreases photosynthesis. As a result, plant growth gets stunted.

This is why plants that don’t get enough humidity don’t flower as much or produce smaller foliage and blooms.

 

How Do You Increase Humidity for Your Houseplants?

The simplest way to increase humidity for your indoor plants is by misting or spraying them with water.

But, the benefits are temporary. When the water dries, its effects are gone.

This means you’ll need to keep misting every so often.

If you stay at home most of the time, this may work. But, it also keeps you from doing a lot of other things.

Additionally, when misting, you need to be aware of how much water you spray. Spraying directly on the leaves or spraying too much can cause excess moisture that increases the risk of disease.

The good news is, there are better solutions.

  • Grouping plants. Placing all your plants together helps increase the humidity in that area. This happens as they simultaneously release moisture through their leaves. Thus, increasing the vapor right above them.
  • Placing your plant on a tray with water and pebbles. This is like a water bath that’s used in baking. But you’ll be using pebbles to keep the plants above the water on the tray. As the water evaporates, it increases moisture in the air which ups the humidity surrounding your plants.
  • Using a humidifier. If you want to be able to control the exact amount of humidity in the room, then using a humidifier is your best bet. This lets you turn things up or down as needed to get the optimal level for your plants.