Pistils Rx: Common Houseplant Care Misconceptions
Ever killed a houseplant? Don’t worry – we all have. As one of our favorite growers says, “You have to kill a plant to know how to keep it alive.” While this attitude might be a bit extreme, it’s really true that personal experience caring for plants is often worth way more than time spent reading indoor plant care books and houseplant care blog posts.
Luckily, between all of us on staff, we have quite a bit of practice – from maintaining our inventory of 500+ specimens, to the plants we care for in our homes, the nursery crew has much to say on the subject of plant care.
This time for Pistils Rx, we decided to hone in on the most common houseplant care misconceptions that we’ve encountered over the years, and what we recommend instead. Like so many other things in life, being more successful at houseplant care can be as simple as a change in perspective. Here’s what Stacey, Ariana, Cate and Chloe have to say on the subject.
Common Houseplant Care Misconceptions
“If I want my plant to get really big I can put it in a huge pot.”
Stacey: There are guidelines with up-potting, and many plants are sensitive to having too much space. Superfluous soil can retain too much water, stressing roots or even rotting the plant in the case of succulents. Excess soil can also encourage pests and bacterial growth, especially if the plant is getting lower amounts of natural light. Ideal up-potting should not exceed an inch or two of new space around the existing pot size, excepting some plants in pots larger than 8 or 10 inches. An easy rule I’d start with is: the old pot should fit comfortably inside the new pot.
“This plant is really hardy.”
Cate: Hardy is a term better suited for plants that thrive outdoors; try not to get wrapped up in what will be a ‘sturdy’ or ‘tough’ plant, but find one that best fits the kind of light you have available in your home, as well as what kind of care you can realistically and easily provide for your plant friend.
“Water your plant once a week all year long”
Ariana: There’s a correlation between light/heat and water; the more light your plant receives the more water it needs and vice versa. During growing seasons, when the light and heat are more intense, plants utilize more water, while heat evaporates it. Rather than scheduling your waterings on a calendar, try using the “finger test” to feel how dry the soil really is before watering.
if my plant is wilting, it’s because I need to water it, even if the soil is wet
Stacey: While wilting is usually the first sign of a thirsty plant, it is not a universal signifier. In tropical plants, wilting is often indicative of stress due to cold, not enough light, pest stress, or any combination of these causes. Plants also often wilt when over-watered! It’s important to keep in mind that, with houseplants, you should never water on top of wet soil. If your tropical plan’s soil is wet and it’s wilting, try moving it to a warmer or brighter location, and examine foliage for any pests. With succulents, wilting or sagging can mean that your plant is not receiving enough light. This is often seen in combination with yellowing of the foliage.
“I shouldn’t move my plants.”
Cate: While some plants can be sensitive to too much moving around, it’s probably a good idea to reevaluate your plant’s home in fall and spring. As the angle of the sun changes, the light a plant receives in its location will shift, making movement necessary. Also, many plants are sensitive to dry, winter air from heating vents, and frequent temperature changes from drafty doors and windows. Staghorn ferns, for example, are rather sensitive to temperature change. When considering where to put these magnificent looking ferns, look for spots that hover around a relatively consistent temperature and are able to receive bright, filtered light. If your best spot happens to be above a rather warm, dry place in your home, be more vigilant in looking for signs of thirst and give a good spritz with a mister every few days between watering. Do you best to keep it away from those drafty spots!
“Ferns live in the forest, so they can tolerate low light”
Chloe: Though the forest floors might seem like dim places, indirect light outdoors is still much brighter than indirect light in our homes. Plus, many of the ferns that are commonly kept as houseplants are from the tropics. Some are adapted to growing in very bright light and warm temperatures. It’s not safe to assume that just because it’s a fern, the plant wants to be kept in the dark. While there are certainly some exceptions, medium to bright indirect light is a safer bet for ferns.
“I kill everything, even airplants!”
Ariana: Despite what you might have heard, air plants (members of the Tillandsia genus) are arguably NOT the easiest houseplant out there. It’s a common houseplant care misconception that they’re impossible to kill. On the contrary, they require precise care, and are very susceptible to rot if not allowed to quickly dry out after watering. If you’re looking for something easier, try Sansevieria, Philodendron cordatum (heart leaf philodendron) and cacti (if you have the light).
“Air plants need only air to survive, no light or water”
Stacey: Air plants are named for their epiphytic nature. Epiphytic plants grow on other plants – in nature, air plants are found growing on trees in the jungle canopy. They need bright, filtered light and regular humidity and soaking to thrive. The frequency of watering changes based on the levels of light the plant receives, but it is important to soak at least every couple weeks. The more light it gets, the more frequently you will soak and mist.
“My plant is unhappy; I think it needs fertilizer.”
Ariana: Fertilizing is an important part of houseplant care but learning when and how much to fertilize is absolutely key. A sudden downward turn in how your plant looks probably isn’t caused by under-fertilizing, but instead caused by a water, light or pest issue. Most indoor plants go into a state of semi-dormancy during winter months due to lower light and cooler temperatures. During this time of year, fertilizing is not recommended, as your plant has no use for the extra nutrients. Additionally, if your plant is showing signs of stress, fertilizing can exacerbate the issue, wait until your plant fully recovers and begins pushing new growth to begin fertilizing again. Be careful not to over-fertilize; less is more. Over-fertilizing can burn tender roots, causing even more damage.
“A layer of gravel is an okay substitute for drainage in pots.
Chloe: There’s a lot of debate about whether or not gravel works as a substitute for drainage, but there’s no question that drainage is always a safer potting option for almost all houseplants. While gravel or stones at the base of a pot without drainage does provide a bit of a buffer, allowing excess water to pool below the soil and away from roots, no matter what’s in the base of a pot, an over-watered plant in a container without drainage is at a much higher risk of problems that in a pot with drainage. Excess water can lead to bacteria and fungal growth, as well as root-rot. If drainage isn’t an option, we recommend activated charcoal at the base of a pot rather than (or in addition to) gravel, as it is absorbent and naturally anti-microbial.
What have your houseplants taught you about their preferred care over the years? What are your biggest problems keeping them alive? Share with us in the comments, and we’ll do our best to answer your questions!