Did you know a cactus could droop? I didn’t until I killed one. Some plants are hardier than others, but if you’re anything like me, the only plant that survives under your thumb is an artificial one. It doesn’t have to be this way. You, too, can keep a plant alive indoors. All you have to do is not kill it. Habitual plant abusers, here’s where we go wrong.
You’re watering them all wrong
Plant killers are intimately familiar with that “oh shit” moment, when we finally realize something isn’t right in yonder ceramic pot. The plant is drooping, and it looks a little yellowish brown. (Or is that brownish yellow?) Discoloration is often a sign of overwatering. The problem is, it’s also a sign of underwatering.
So how do you know if you’re watering a plant too little or too much? If you examine the plant a little more closely, you should notice some subtle differences that tell you whether it’s drowning or thirsty. Here are some symptoms unique to both conditions, based on info from HomeGuides and Jain, an irrigation company.
Overwatering
The base of the plant stem feels soft and mushy
The tips of the leaves turn brown
Yellow leaves throughout the plant that fall off
The top two inches of soil are moist
Underwatering
The edges of the leaves are crispy and brown
The leaves start to curl
The lower leaves are in worse shape
If you’ve underwatered your plant, the solution is easy: water that thing! If you can’t get the hang of it, tech can help. For example, Vera (iOS) is an app that will help you create a schedule for the care and watering of your plants. Enter details about your plants to create an individual profile for each, and create a watering schedule with built-in reminders. It’s not foolproof, but if you’re bad with plants, an app is probably more reliable than relying on your own memory. You could also use a digital sensor to tell you when the soil is dry.
If you overwatered your plant, you’ll have to remove it from the soil to bring it back to life. HomeGuides offers step-by-step instructions for saving it, but the they boil down to cutting off the soft, rotten roots of the plant and repotting it in a pot with proper drainage.
Speaking of drainage, most plants need it, and when they don’t get enough, they suffer root rot. A hole at the bottom of your container may not be enough, either—the water needs a place to go, like over rocks or through a drainage tray.
You picked a terrible location
When you choose a place in your home for plants to live, pay attention to three main factors: lighting, temperature, and humidity.
Lighting should be an obvious one—the requirements are right there on the plant’s tag. (And if there is no tag, you can look up the requirements using this online database). It can be confusing, though. Some plants require “low light,” but what exactly does that mean? How low is too low? MyCityPlants suggests conducting a noon light test to figure it out:
At noon — when the sun is brightest — stand in the spot where you want your plant to live. Look down at your shadow, and if it’s a...
Strong, well-defined shadow, then you’re swimming in
Bright Light
.
Weak shadow but you can still make out the silhouette, you’re working with
Medium Light
.
Faint shadow without much definition, it’s a
Low Light
spot.
This should help you figure out the best spot for your plant, based on how much sun it needs, but the direction of the light is another useful measure. According to Fifth Season Gardening Co.:
South facing windows are the best with bright sun all day, good for any plants with variegation or trees like citrus and banana. If a plant needs medium light, just locate it to the side ... or a few feet away from the window.
West windows get a long period of direct sun, but usually miss the hottest most intense part of the day, which can damage some plants with medium light requirements.
East windows are perfect for most low to medium light requirements that smaller, table-top plants prefer. The sun is much less intense in this orientation.
North windows limit wise choices to a small selection of house plants. In general, flowering plants, like african violets or orchids struggle to survive in any north facing window.
If you have a darker home, consider these plants, which do well in low light. In fact, here’s an entire flowchart to help you pick the right plants based on your lighting environment.
As for temperature, most plants do well at temperatures between 65-75 degrees, which is generally how cool most of us keep our homes. Pay attention to hot or cold spots in your home, though: right under a vent or near a blazing hot window, for example.
Finally, humidity is a factor when watering a plant, too. Some plants, like most ferns, thrive in really humid environments (like your bathroom) and need at least some humidity to survive. Look up the requirements for your specific greenery using a search tool like Garden.org’s Plants Database. If your moisture-loving plant is in a dry environment, spritz it with water every couple of days to make sure it’s getting the humidity it needs.
You’re shocking them
Change can be tough on any of us, and plants are no exception. When you take them home from the store and immediately shovel them into a new pot, in a new location, with even a slightly different temperature and lighting situation, they can experience transplant shock.
As Gardening Know How explains, preventing transplant shock begins with the roots. Handle the root ball gently when transplanting and bring up as many of the roots as possible.
Sugar helps, too: A 2004 study published in the Journal of Arboriculture (PDF) found that feeding plants sugar can help reduce shock:
This finding indicates that the growth pattern of trees may be altered in favor of enhanced root formation by treating them during or immediately after transplanting with sugar, potentially offering a system for reducing tree mortalities due to transplant shock.
When you transplant, add some sugar water to the mix, be careful with the roots, and you should be in the clear.
You’re using the wrong soil
Soil matters, so don’t just go to the garden store and grab a bag of whatever. Picking the right soil can get complicated, especially if you’re into gardening and raising fruiting plants. For those of us just trying to keep our potted green friends alive, Proven Winners suggests a few simple rules of (green) thumb.
Container potting soil should be light and fluffy.
For containers, just use a regular potting mix. Look for a bag that says “Soilless potting mix.”
Some plants, like orchids, need an especially good amount of drainage, so they have their own specialty potting mix.
Beyond the basics, there are some other factors to consider.
pH balance: The mix will usually tell you how acidic or alkaline the soil is on a scale from 0-14 (7 is neutral). Here are the ideal pH levels for some common houseplants. Most plants thrive in the 6.0-7.0 range, according to The Old Farmer’s Almanac.
Soil weight: Soil is typically classified by how dense it is: light, medium, or heavy. As a basic rule, a medium soil is good for plants in full sun, because the soil holds water. Light soil works well for hanging plants or plants in indirect sunlight or shade. Heavy soils are typically used for outdoor plants, gardens, and trees.
Organic versus nonorganic: As HomeGuides explains, organic potting mixes provide nutrients for plants over time. As their organic materials break down, they release nutrients. Nonorganic soil, on the other hand, contains enough fertilizer for a single season. After that, you might want to consider adding your own plant fertilizer.
Fertilizer: Speaking of fertilizer, it can be tricky. Adding too much can kill your plants, and as the New York Times notes, if the plant is thriving, it’s best not to bother. “If the plant is putting out new growth, is flowering or is growing well and looks strong, then it is doing well. Don’t push it.” However, they say plants that are growing under fluorescent light or have been sitting in the soil at stores could probably use a dose of fertilizer, and they recommend using a water soluble type with a ratio of 20-20-20, which is suitable for most houseplants.
There’s a lot more that goes into picking the right soil, but for the sake of simply keeping your plant alive, these basic rules should work.
Finally, it helps to know how to read your plants to begin with. This way, you can pick up on early signs of suffering. In addition to comprehensive “plant profiles,” Dave’s Garden’s Plant Files database includes thousands of user-submitted photos and reviews that will tell you what your plant’s leaf color and blooms should look like when they’re healthy.
I envy my green-thumbed friends who seem to have an intuitive sense for how to help plants thrive. The rest of us can use these steps to troubleshoot the problem. Hopefully, you’ll be on your way to raising plants that, if not thrive, at least survive.
This post was originally published in May 2016 and updated in September 2020 to refresh the content and update dead links, as well as align it with current Lifehacker style guidelines.