Rubber Tree Care: How To Give Them Just Enough Water & Sunlight

The rubber plant or rubber tree (also known by its very fitting scientific name, Ficus elastica) makes for a dramatic and relatively low-maintenance indoor plant.

Rubber plants are also known as Indian rubber tees since they're native to Southeast Asia. They can grow to over 50-100 feet tall in outdoor habitats and were once prized for their sap, which was used to make rubber in the 1900s.

The Amazonian rubber tree quickly replaced it for this purpose, but the Ficus elastica's sap is still used medicinally in a few cultures—though it can be poisonous to cats and dogs, so pet parents should steer clear of this one.

The main mistake that Monai Nailah McCullough, the horticulturist and founder of Amsterdam-based shop Planthood, sees people make with rubber plants is underestimating their lighting needs.

"The Ficus elastica actually needs a lot more sun than its other ficus cousins," she tells mbg. "If you ever see it described as a low-light plant, it's a lie! They do a lot better in fuller sun." Feel free to put this one in a spot that receives a few hours of bright, direct sunlight every day.

NYC-based houseplant enthusiast and chemistry teacher Paul Thompson, M.A. has seen his thrive in an Eastern-facing window. "The less light it's getting, the slower it will grow, so don't be afraid to put these in brightly lit areas," he says.

If you start to notice your plant develop light brown, crispy leaves, though, it's a sign it might be getting too much light. In this case move it further away from the window or invest in sheer white curtains to block some sunlight during bright afternoon hours.

Since this plant can be a fast grower, especially when it's getting enough sun, it appreciates the occasional fertilizer feeding too.

Like many tropical trees, rubber plants like to be watered when the top 2 inches of their soil are totally dry to the touch. They also enjoy the occasional mistist, especially when the air around them is dry.

"Trees store water in their trunks for the drier seasons," McCullough explains, so they can typically go a week or two without water and be totally happy—though if yours is placed in a really bright spot, it might need to be watered a bit more frequently.

Stick your fingers into the top layer of soil to be sure. If it's dry to the touch, water with room-temperature water until it starts to leak out of the drainage hole at the bottom.

When water starts pooling in your plant's tray, you'll know it's had enough to drink. Give your tree 15 minutes to drink up the last of that liquid. If there's still any water left after that, toss it so it doesn't drown your plant's roots.

"You don't want water to sit in that plant—it can go south very quickly," says McCullough.

Some signs that your plant is overwatered include prolonged wet soil and soft, dark brown leaves. If you spot these, stop watering, move to a brighter spot, and let the plant dry out for a while.

Fungus gnats, spider mites, mealybugs, and other plant pests can flock to the rubber plant's thick, meaty leaves. Get in the habit of wiping the leaves of yours down with a damp towel every so often to look out for the telltale signs of pests: tiny holes; unexplained yellowing, slimy, sticky residue; or small eggs.

"Pests will always lay their eggs on new, fresh leaves because they have a lot of the plant's energy and chlorophyll development," McCullough says, so pay extra attention to those.

Rubber plants should be moved to a new pot every one to two years.

Signs that your plant has outgrown its home include roots that stick out of its pot's drainage hole, peek through its top soil, or press against the side of its container.

Spring or summer is the best time to move your plant into a new container that's 1 to 2 inches larger in diameter.

Another good habit to get into during the start of growing season is pruning your tree.

Without pruning, rubber plants often grow upward and not outward, causing them to look a little leggy. To encourage more fullness, you can cut a few of its top leaves off at their internode—the part of the stem right underneath where the leaf juts out—using shears. These clippings can then be propagated in water and replanted if you'd like.