Counter Seasonal Depression with Houseplants

In the fall, humans tend to fall into depression, a condition experts call “seasonal affective disorder” (SAD). Most of us would simply call it winter depression or winter blues.

There are many symptoms: decreased energy, loss of interest, isolation, insomnia, etc. The cause is not well understood, but the idea that the dull, gray weather of fall and winter is behind it, as was formerly believed, has been largely debunked. Instead, the most common current theory is that it’s due to reduced day length. According to this hypothesis, humans evolved in the tropics, where days last about 12 hours throughout the year and because of that, we have a hard time coping with days less than 12 hours long.

I’m not pretending to be a psychologist here: if you suffer from deep depression during the winter months, of course you should consult a specialist! But if you only feel slightly depressed in the fall and winter, there are several ways fairly simple ways of dealing with it.

One treatment for SAD that is currently very popular is luminotherapy (light therapy): daily exposure to an artificial source of more than 2,000 lux of white light. You can easily buy special lamps for that purpose. You simply turn them on and spend a few hours a day in front of them. Those that produce closer to 10,000 lux require less time, perhaps only 30 minutes of exposure.

Still, these lamps are expensive and require quite a bit of your time. Fortunately there is also a less expensive therapy and, in my opinion, a more pleasant one: surrounding yourself with plants.

How Plants Help Your Health

There are literally hundreds of studies that show the mere presence of plants in human environments has a beneficial effect on their health, both mental and physical. Exactly why this is true is a subject of much discussion, but working with plants (watering them, repotting them, etc.) has a guaranteed calming effect. It somehow seems to soothe the mind. In fact, it would appear that even just looking at pictures of gardens is good for the psyche! This is why more and more hospitals and nursing homes are now incorporating outdoor gardens and indoor green spaces, not just for decoration, but because their patients actually profit from them. Even in schools, students appear to learn more readily and to retain more information when the classroom contains a few plants.

This information has not been lost on employers. Employees in offices that include living plants are absent less frequently and benefit an improved sense of well-being. Productivity increases considerably… and profits go up too!

Obviously, some of these effects are physical: living plants do filter the air of impurities, increase oxygen levels (very slightly), improve relative humidity and reduce background noise, all of which positively affect human health. But the psychological effect seems even more important. How else can we explain the fact that people who see plants from afar and are never able to approach or touch them or to take advantage the filtered air they provide nonetheless feel happier and less anxious?

Still, some employers see plant maintenance as unnecessary expense and recent years have seen a decrease in indoor plants in some workplaces as a cost-cutting measure. If so, perhaps you could get permission to bring plants of your own as long as you take care of them yourself? Or form an office committee to look into the situation and present proof to your employer that it is actually cheaper to maintain plants in a working environment than to remove them.

Plants in the Home

You don’t have to fill your home with plants in order to take advantage of the psychological effects of their presence: a plant here and there or a small grouping of plants in the corner of the room is all it takes to reduce stress.

To be effective, however, plants have to be alive: dead, brown plants are of no benefit. That means you have to consider what plants need before adding them to your décor.

Remember first and foremost that light is the only source of energy plants have. Fertilizers don’t “feed” plants, in spite of what fertilizer sellers purport, the sun does. So places where you intend to grow plants must receive at least some light. Some plants – cacti and most flowering plants, for example – require a lot of light to grow well. Keeping them alive elsewhere than on a sunny windowsill won’t be easy. Most so-called foliage plants, on the other hand, can grow in fairly dim spots and are often the easiest varieties to grow.

Also, you need to water them. There is no fixed rule as to watering frequency: depending on conditions, the same plant may need watering every five days or every two weeks! You really have to physically check the condition of the plant’s soil. Do so twice a week, pressing your index finger into the potting soil: if the soil feels dry to the touch, water thoroughly, enough to moisten the entire root ball. If the soil still feels damp to the touch, don’t water. It’s as simple as that!

What about fertilizer? It’s only a minor factor: don’t knock yourself out over it. Apply fertilizer (an all-purpose one is fine) at a quarter of the recommended dose from spring through mid-fall and most houseplants will grow wonderfully.

Increasing the humidity in winter with a humidifier will benefit virtually all foliage plants, but some, like the snake plant (Sansevieria trifasciata) and the Chinese evergreen (Aglaonema spp.), tolerate dry air quite well. Here’s a bit more about plants that tolerate dry air.

Finally, when it comes to indoor temperatures, almost all plants sold as houseplants are perfectly comfortable with typical indoor temperatures, so that’s one less thing to be concerned about.

Plants That Put a Smile on Your Face

Here are some indoor plants well known to be easy to grow and to be able to help purify the air in our homes and offices. Growing a few of them could quite possibly help you get over the winter blues!

• Boston fern (Nephrolepis exaltata cultivars)
• Chinese evergreen (Aglaonema spp.)
• Dieffenbachia (Dieffenbachia spp.)
• Dracaena (Dracaena spp.)
• Ficus (Ficus spp.)
• Palm (various kinds)
• Philodendron (Philodendron spp.)
• Pothos (Epipremnum aureum)
• Snake plant (Sansevieria trifasciata)
• Spider plant (Chlorophytum comosum)
• Syngonium (Syngonium spp.)