It’s January and we’re spending lots of time indoors. That means artificial heat, little daylight, and more inhalation of polluted air that contains volatile organic compounds. The first two conditions lead to drier skin and lowered immunity against diseases like colds and the flu. The third, inhalation of VOCs, can lead to respiratory issues, headaches, dizziness, hormone disruption, and even organ damage and cancer.
VOCs are nasty. They’re the toxic fumes and dust emitted via gases from furniture, carpets, paint, and plastics. We can’t see or smell them. They’re barely detectable. But we breathe them in every day. They, along with dry heat and darkness, can potentially harm our bodies at this time of year.
When we’re not physically healthy, we feel less energetic to take on the world. We’re not as alert, we’re tired, and sicker than we are in summer. This in turn causes us to miss out on things we otherwise enjoy. But the good news is common house plants can help neutralize the harmful effects of living indoors.
How Houseplants Can Help You
According to various scientific studies, there are four main physical benefits of growing plants indoors. In some cases, you don’t need a lot of money or effort to gain those benefits either. Here they are.
1. It only takes a few plants to clean the air. There’s a famous NASA study that proved plants clean the air of toxic fumes like formaldehyde and carbon monoxide. This study’s been cited a lot by various articles but because it was conducted in small, controlled chambers, it’s also been somewhat criticized. However, follow up studies have solidified the National Aeronautics and Space Administration’s results. They show that plants reduce harmful gases in the air. In some cases, only six shelf-sized plants were needed to reduce volatile organic compounds by as much as 75%. Wow!
2. Humidity rises easily through plants. Most folks don’t realize that our indoor air is way too dry. We often live in heated homes where the humidity is below the 30–60% needed for our bodies to be healthy. When humidity is too low, we suffer from more frequent colds and dry itchy skin. Washington State researchers found that plants using less than 2% of a room’s space can raise humidity by 5%. This study also mentioned how too much humidity is rare because when the air is humid, a plant slows its evaporation. So if you grow several plants together, your air should feel more comfortable.
Two More I Didn’t Know About
3. Plants reduce dust accumulation. This one surprised me. Researchers found adding plants around the edges of a room reduced particulate matter on horizontal surfaces by as much as 20%, even in the center of the room. This is weird because you’d think that plants create more dust and particulates from dirt but the opposite is the case. The only clue as to how this happens is the researchers’ conjecture that particulate matter is reduced by “impacting and adhering to plant surfaces.” In the meantime, you could conduct your own experiment by growing several houseplants and see if they help keep your home clean.
4. Plants lower noise under certain conditions. A 2003 study found that plants can absorb or break up sound, depending on the frequency. Rough bark and thicker, wider leaves are particularly effective at absorption. Plants with dense foliage are better too. And of course, the larger number of plants, the more sound is neutralized. Also, placement has an effect as well. But researchers learned that plants, like carpet or furniture, neutralize sound waves and reduce noise.
If Nothing Else, Try This One Simple Thing
In the meantime, to improve your health, you can try one simple thing today. And you only need to do it for five minutes. Take a walk outside. Inhale the fresh air, feel the cool moisture on your face. It may be a bit noisy and maybe even a bit dusty, but scientists say outdoor air is oftentimes healthier than indoor air. If it’s convenient, you can head for your nearest public park to take in the healing sight and smells of greenery. A short walk will not only get you into the daylight and circulate your blood, it’ll boost your mood and get you in touch with the joys of autumn.
One morning this last fall, my friend Angela called to say she had some orphaned plants she wanted me to have because they needed a good home. You may remember Angela’s a dear friend who’s a container designer and regularly switches out arrangements for clients. In this particular instance, she’d redesigned some summer pots for fall and had a bunch of leftover babies.
Before I could blink, she was pulling into my driveway with a miscellaneous collection of pots and paper bags. The goodies contained bromeliads, crotons, a spider plant, and mandevillas. While I had some experience growing the first three, I’d never grown a mandevilla, outdoors or indoors. But I was game to give it a try.
What’s a Mandevilla?
For those interested, a mandevilla is a huge genus of vines that grow in tropical places like South and Central America. Some even grow in the southern United States. They can grow up to 15 feet, even higher given the right conditions. And those conditions are strong sunlight and warmth, which of course we don’t have much of during a rainy Seattle winter. But they can function as a houseplant.
The three mandevillas Angela gifted me all had the same strong darkish pink flower. Its trumpet-shape has inspired the common name, rocktrumpet. Unfortunately, I’m not sure of the cultivar. It’s somewhere in the black hole of Angela’s notes. But luckily I’ve been able to keep them alive well enough.
How to Grow a Mandevilla Indoors
Here’s what I’ve been doing that works.
First, I set it up in the sunniest window of my house, a south-facing living room window. It was okay there but after a few days, I put a grow light over it and it became much perkier. Its little vining shoots extended. It appreciated the bright light and extra warmth.
Second, I noticed some older leaves yellowed and dropped a couple weeks after I brought it inside. I discovered this was from the sudden warmth of dry heating vents that had started blowing in October. I cleaned up those dried yellow leaves and cut off whatever stems had dried out as well to deter pests. You can spot dried stems by their suppleness and color. Happy stems are always soft and greenish. Dried ones are blackish green or brown.
Third, I increased humidity near the plants. In one case, I misted the plant regularly. I actually don’t think misting is very effective but I didn’t have an extra diffuser so I sprayed the plant from a misting water bottle every few days. And sprayed liberally. You need to pretty much make sure the plant is soaked if you want the plant to absorb moisture before the droplets evaporate.
Fourth, I tapered off watering. I was watering lightly every week and now in the heart of winter, I’m watering about once every ten days. This has seemed to make the plant quite happy. And so far pests have not visited it even though mandevillas can attract pests if overwatered.
Fifth, in December, with less watering comes less light. I now turn on the grow light once every week rather than once every couple of days. It knows it’s winter and to be dormant. It’s not blooming and won’t for a while.
Heading into spring, I’ll let the season’s light do its work and turn off the grow light until next October. I’ll water every week again as the light strengthens. I’ll install trellises so its vines can latch onto a structure. And every month, I’ll add some fertilizer to see if it will bloom again.
We’ll see how things go. I might even put the plants outside in a hot sunny location. They thrived in Angela’s client’s garden so I might have the same luck. If those gorgeous flowers do bloom, the hummingbirds will surely visit and that will give me the best gift of all.
If you’ve followed this blog at all, you probably know that I’m charmed by African Violets (Saintpaulia). I mean, I did write a whole novel about a magical one! That’s because I adore everything about these little guys. I love their fuzzy leaves. I love how they grow in almost perfect, rounded whorls, and I love their cheery upright flowers. The colors vary from purple to magenta to pink to yellow, white, and so on. And the flower forms range from single to double to fringed to striped and more. But did you know there’s an even more unusual African Violet? It’s the Variegated African Violet.
The Variegated African Violet
Variegated African Violets have been around since the late 1950s. Their leaves are usually edged or speckled or streaked with white but this varies. Some have white interiors, some have yellow new growth, etc. They bloom most commonly in purple and pink and occasionally you’ll find a double-flowered variety, which is really special. Like regular African Violets, they’re easy enough to keep alive though a Variegated African Violet is a bit trickier.
Caring for a Variegated African Violet
My Variegated African Violet, whose cultivar name I’m still not sure of, boasts serrated leaves and lots of vivid white on the margins. When those leaves emerge, they sport a dusty pink color. My heart soars whenever I see this small but pretty feature.
I grow my African Violet in a south-facing window with partial direct sunlight. Traditionally, they like bright indirect light. They also like a warm room and extra humidity though I’ve always grown mine just fine without added pebbles in water. (Note, I do sometimes use a humidifier in winter.) But there are a few tricks to keeping a Variegated African Violet happy. Here’s what I’ve learned:
- They don’t like a lot of harsh sun. Because their leaves have that white color, they don’t have the extra chlorophyll to take in sunlight. So don’t let it get scorched in a sunny window. Grow it in a north- or east-facing window if you can.
- They dry out more quickly than regular African Violets. But instead of watering them more frequently, I water them with more water, like more thoroughly soak the soil. This seems to keep them happy.
- Speaking of water, they like room temperature water, not cold water. It shocks their roots.
- Don’t fertilize too often or the variegation will fade. I fertilize mine once a month during spring and that’s about it.
- Because they grow natively in Africa, they like warmth! Don’t chill them by setting them in too-drafty of a window and don’t turn down your heat below 60 degrees at night.
Like all African Violets, you never want to let water splash onto the leaves. It’ll create spots. And remember, don’t water every few days. I water mine every 7-10 days and they seem to do well on that schedule. I also rotate the pot so the leaves grow in a more even pattern. But in the end, I also don’t overthink their care. If you put yours in a bright warm window and water every week or so, they should be fine. And, if they bloom, you’ll know you’re successfully keeping your Variegated African Violet happy!
In Spring several years ago, we adopted a big black dog. He was a Belgian Shepherd mix about six months old with pointy ears and a pointy nose, the largest dog my husband and I had ever owned. I’m 5’6” and he came up to my mid-thigh. Since all of our dogs have had or have names that start with vowels, Arrow, Iris, Olive, we named him Ezekiel. With a brassy bark and sharp brown eyes, he looked more like a Zeke so we started calling him Zeke.
Zeke liked to roam the perimeter of our yard, woofing at crows that flew overhead, chasing squirrels that ran up trees. He also liked to bark at our neighbors behind the fence as they got out of their car. Inside, he followed me everywhere, convinced I needed guarding. It was how he earned his second nickname, “The Sheriff.” And on nights when his body dissolved into the darkness of the front yard, I’d call for him, saying, “Are you Shadow, the Direwolf?”
A Pet Den of Smells
In our bedroom, Olive slept on her bed beside me, our cat Maddie between our pillows, and Zeke in the corner near my husband. (Our other cat, Aleksy, likes to sleep with my daughter.) Unlike Olive, Zeke didn’t snore like a buzzsaw or whimper like Maddie. He just plunked into sleep every night, breathing deeply and solidly, probably relieved to have found a “forever home” after being returned to the shelter more than once.
A few weeks into our slumber ritual, I noticed a trend. With warm spring nights and three pets and two humans breathing in the same room for eight hours, the room stunk in the morning. Like dog. Strong dog. Oftentimes, like wet dog. I’d wake up to damp air and animal musk smells. It was not fun. I considered buying an air cleaner but I wasn’t sure it could truly help me. An air cleaner pulls particles out of the air like dust. I wasn’t sure it could process scents. Then it hit me: a plant could clean this musky indoor air.
A Peace Lily Plant, Nature’s Purifier
I had always grown houseplants but I’d never put any in our bedroom. Aleksy liked to chew on the stems in the early hours. So, I bought some metal screening. With tin snips, I made a circular fortress to keep the cat out. Afterward, I was unsure which plant to choose. I already owned several to clean indoor air: devil’s ivy, dracaena, snake plant, ferns, etc. I wanted something I hadn’t grown before.
A few days later, as I was roaming through a local nursery, I found a lush plant of dark green leaves. Its wands of white flowers faintly resembled calla lilies. The blooms held a tall oval bract around a spadix. It was a Peace Lily (Spathiphyllum). I bought it and a new ceramic container and potted it up. Peace Lilies like shady conditions so in the bedroom I set it atop my husband’s dresser, about four feet from the window. I watered it and set the metal fortress around the pot, hoping it could clear the air in a few weeks.
Well, it didn’t take a few weeks, it took all of three days. It worked its magic at night until one morning, I woke up and inhaled neutral clean air. I thought, “Gosh, it doesn’t smell in here. Why?” The plant had taken in the foul air through the miniscule holes in its leaves and had exhaled fresh oxygen. I’d solved the dog musk issue.
Peace Lily Plant Profile
Peace Lilies are ideal house plants because they take low light and aren’t fussy about soil. When happy, they bloom for six or more months. They like watering and require a drink twice a week. Big rooms need more than one plant. Their air-cleaning talents only cover about a six-foot square space. But tucked among other houseplants of various textures and sizes, they can be part of a peaceful green sanctuary. Then at night, with or without a big black dog, one can sleep well and breathe easy.