At the start of the pandemic – when I was told to work from home instead of going to the lab where I worked every day – I found myself getting demotivated. Understandable really; it was a big upheaval, and very stressful for all of us. I was getting fed up of staring at the same four walls, and ultimately decided I would try to make the place feel a bit brighter. Like many people, I decided to buy a bunch of houseplants.
I already had one houseplant, a gift from friends when I first moved into my current home. But when I’d been working in the lab it was very easy to walk past it every single day as I left in the morning or arrived home in the evening, and not think twice about what it needed. It had lost a lot of leaves and it was looking pretty scabby.
Now, though, I was home every day so I could pay more attention to it. I trimmed the dead leaves, I put it in fresh soil, I actually watered it when it needed it and it started to thrive and grow new leaves. And, of course, that felt good; I’d nurtured something into good health at a time when the world felt very unstable and scary.
So I bought a few more house plants to brighten up the place. And a few more. And a few more. Pretty soon I, like many millennials, had my own mini jungle. I learned about how to care for different types of plants. That my Boston fern likes a lot more water and light than I initially realised and goes crispy and brown when it’s not getting enough. That my Pilea peperomioides will climb towards the light looking like a plant from an alien planet instead of being cute and stocky like the ones I see in photos on Instagram. That spider plants are the devil that grow more new plants than you can ever know what to do with until they entirely take over your home.
One night, I even settled into an evening with a glass of wine in front of my computer watching a live webinar on how to care for my aforementioned tricky Boston fern. Shut up, I’m autistic and a millennial – of course this became a special interest for a while.
But the more I learned about caring for my jungle of house plants, the more I realised that there are a bunch of recommendations and beliefs that just aren’t based in the science. Growing living things is, of course, a science. And we do know lots about how plants grow and what they need to thrive from botanists who research these things. But that doesn’t mean that us amateurs won’t end up believing strange things when our plants are behaving oddly.
We’ve talked in this magazine before about some of the lack of science around reusing coffee grounds or dish water for plants so I won’t touch on those. But aside from that – here are my top five house plant myths….
Myth 1: Misting
I came across the idea of misting quite early on in my houseplant journey. That’s because I have a lot of prayer plants. The Calathea genus of plants, also known as prayer plants, are mostly found in tropical climates where there is a lot of humidity. And I have plenty of these plants because they are pet friendly, and I have two dogs. They also look pretty cool and have a neat quirk in that they open out their leaves in the morning and lift them up at night.
When you start looking up how to look after these tropical plants, though, you find out that plants from tropical climates need humidity. So the recommendation is always to spritz them with a mist of water. Pretty misting spray bottles are available in all the trinket shops and if you’re a plant lover you will surely be gifted a misting bottle – in fact I’ve gifted them myself. Turns out they’re a bit of a waste.
Botanist James Wong was skeptical of the value of misting but he also noted that there hadn’t really been any research on it. So he conducted an experiment in his living room and found that (at least in his living room) any increased humidity created by misting was gone within thirty minutes. You’d need to be misting pretty constantly to give your tropical plants an environment similar to that of a topical climate. Still, all my Calathea’s seem pretty happy without any misting as long as they get all the other things they need. Which brings me to…
Myth 2: If your plant is doing badly you just need to water it more
Most people I know forget to water their plants. So, it’s easy to see why people think the solution to a sick plant is to water it more. Scientifically we know plants have a range of needs and there are many other reasons plants might look a little sickly – we might have put them in an area with insufficient light, or an area with too much direct light. They might be infested with insects or infected with fungus. Or they might need some fertiliser.
But what’s the downside of watering a sick plant? Well, plants are just as easily damaged by overwatering. When we overwater our plants we risk root rot. The soil doesn’t get chance to dry out and the roots start to break down. This can be even more damaging than under watering.
One way to prevent this is to water your plants in a different way – instead of taking a watering can to your house plants, take your houseplants to the sink. You can run water through the soil and allow the water to drain out of the drainage hole in the bottom of the pot. Once the water has finished running through you can take your plant back to its decorative pot cover safe in the knowledge it won’t be left sitting in the water that collects in the decorative pot if you over water it in situ.
But there is another reason plants can get root rot and that comes from…
Myth 3: Bigger is always better
If you keep plants you might have heard of root binding. This is what happens to plants when they outgrow the pot they’re living in. The root mass gets so significant that there’s just no space in the pot for more growth and the roots get compacted down. So, when a plant outgrows its pot, you need to move it to a bigger one. But that doesn’t mean lobbing your plant in a massive pot will allow it to grow and grow and grow.
A pot too big can cause damage to our plants as there is so much soil that it stays waterlogged when we wet it. If there is too much soil for the roots, the water doesn’t get absorbed out and the soil never gets dry. The roots stay sitting in damp conditions and start to rot.
This might all seem very complicated, which might lead you to think – plants are hard work. Why don’t I get one of those easy to care for plants like a cactus or succulent? Which brings me to…
Myth 4: Cacti and succulent plants are SO easy to care for
In my friend circle I am known as the plant nurse. I have learned how to bring a very sick plant back to life. But I have killed so. many. succulents. While they can do quite well without too much water, they do need watering from time to time and they need lots of sunlight and can get root rot from over watering. They’re also a little less expressive than other houseplants – other plants might get yellow or crispy leaves when they need something, or they might wilt when they’re thirsty. But the changes in succulents and cacti are subtler and harder to read. I’ve had cacti trundle along quite happily looking completely normal until the day they are suddenly irreversibly sick.
The other common mistake with cacti is popping them in a terrarium. Terrariums are for creating humidity and cacti are from climates that are famously very dry. Terrariums are not a good place for a cactus.
Myth 5: You must not keep house plants in the bedroom
This is a persistent myth. I remember as a child being told I wasn’t allowed a plant in the bedroom. And it made sense. We all know that plants take in carbon dioxide in the day and release oxygen. But at night they take in oxygen and release carbon dioxide. So, we are told, if we want to breathe well why we sleep, we need to avoid house plants in the bedroom.
Even some light questioning on this should expose the errors in this thinking. Many of us share our rooms with another human or our furry friends. I typically share my bedroom my partner and two dogs. There’s four of us sharing the air in the room without any cause for concern. Plants don’t generate nearly enough carbon dioxide to cause problems in our bedrooms. Plus, the houses we live in aren’t tightly sealed – the air is circulating all the time.
Why are we prone to believing these house plant myths? Well, I think it comes down to wanting to do the right thing. Here we have a living organism that we care about and feel responsible for, and when it gets sick we feel like we did something wrong and want to do the right thing to keep it well. So we look for advice, and we might change a handful of things all at once in the hope that something helps make our plant happy again, and when it does we confirm to ourselves that the magic solution worked and keep at it. We don’t question which of the things we tried is actually responsible. And after all, it doesn’t really matter if it’s something as simple as spritzing the air a few times a week.
The post Five persistent myths about caring for houseplants, and why they’re wrong appeared first on The Skeptic.