Striking a moisturized middle ground usually isn’t too tough; it just takes some intuition and a dash of plant know-how. Here, two experts with a combined 275-plus houseplants between them explain how to decide when to water all your plant pals. “It’s not a one-size-fits-all for watering. It really depends on the need of the plant, how much light it’s getting, the type of soil, all that,” Thompson tells mbg. He adds that your plants’ watering needs will also change throughout the year as different seasons lend different light levels. These three strategies can help you tell if your plant needs water or not: “Use your finger like you would a cake test,” McCullough says. Stick it about 2 inches into your plant’s soil (a good way down your finger) and feel around. If the soil is totally dry to the touch, it needs water. If it’s still wet, move on and wait to water another day. If you don’t want to go by feel alone, you can also observe what your finger looks like after this little probe. “If you stick your finger in and there’s water, you’ll have some dirt on your finger when it comes up. If you don’t, the soil is pretty dry.” Again, think cake-tester: Residue on your finger means that the plant needs to go “back into the oven” so to speak, and dry out a little more before it’s ready for watering. For those who don’t want to get dirty, using a chopstick for this would work too. No matter the tool you’re using for this method, it’s important to really get in there. Don’t just graze the surface level of the soil; get down to root level. And don’t worry about disturbing your plant—chances are it will appreciate the extra aeration, which keeps its soil from getting compacted over time. A few nice things about moisture probes: They’re more exact than the finger test and give you more information about the moisture differences between soil levels. You can stick the probe in the topsoil and then compare that reading to the number you get lower down in your pot. Getting a similar reading throughout the plant shows that you’re doing a good job watering evenly. If your soil moisture levels are patchy, you might need to readjust your watering technique (more on that below). This method isn’t as exact and should probably be combined with steps 1 or 2, especially for newer plants that you’re still getting to know. If you don’t want to do a daily check, loosely grouping your plants by their watering needs—i.e., putting all your desert succulents in one place and moisture-loving ferns in another—can help you stay organized. In that case, you’d want to observe your thirsty ferns every week or so but could get away with going longer between succulent checks. Then, give your plant a few minutes to drink up the water that’s collected in its saucer. If there’s any water left after 15 minutes, dump it in the sink. Your plant doesn’t need it, and leaving it sitting there could drown out the roots. But again, if you feel you keep tabs on soil moisture, water only when your plant really needs it, and stop watering once you see water coming out of your pot, you should have some happy plants on your hands. The same general rules apply for watering outdoor plants as indoor ones: Make sure the soil is dry to the touch first, and soak it thoroughly until water starts running out of your pot’s drainage hole. For garden plants, water thoroughly, until the surrounding soil is moist. You don’t have to worry about overwatering plants in the garden as much, but wilted leaves could be a sign you’ve gone too far. Emma received her B.A. in Environmental Science & Policy with a specialty in environmental communications from Duke University. In addition to penning over 1,000 mbg articles on topics from the water crisis in California to the rise of urban beekeeping, her work has appeared on Grist, Bloomberg News, Bustle, and Forbes. She’s spoken about the intersection of self-care and sustainability on podcasts and live events alongside environmental thought leaders like Marci Zaroff, Gay Browne, and Summer Rayne Oakes.
