How to grow and care for a ZZ plant

• The ZZ plant is low-maintenance — it can tolerate infrequent watering and indirect sunlight.
• Avoid watering ZZ plants until the soil is bone dry, as overwatering can cause root rot.
• Use well-draining soil, only fertilize in the spring, and repot the ZZ plant every year or two.

With its spotless shiny leaves that have an unusual waxy finish, the ZZ plant — also known as the Zanzibar gem or its scientific name, the Zamioculcas zamiifolia — is so striking that it's often mistaken for artificial. It's also known as the "plant of steel" as it can tolerate low light and infrequent watering without making a fuss.

According to Erin Marino, houseplant expert and director of marketing at The Sill, this is because it's native to arid regions like Zanzibar, Kenya, and Eastern Africa, which often experience ​​long periods of dry conditions with occasional bursts of rain.

As such, Marino says the ZZ plant has evolved to adopt characteristics that help it withstand drought. You might notice large potato-like bulbs under the surface of the ZZ plant's potting mix. These are known as rhizomes, and are actually underground stems, according to Marino.

"The rhizomes store water to help the ZZ plant survive when rainy days are few and far between," says Marino.

All that said, there are a few things you should know about caring for this indoor houseplant. Follow the expert-approved guidance below to ensure your ZZ plant thrives.

Common ZZ plant cultivars

There are at least a dozen different cultivars — or cultivated varieties — of the ZZ plant, with new ones emerging all the time. Unlike standard plant varieties, which occur as a natural phenomenon, new cultivars are purposefully created when growers crossbreed two parent plants that have desirable characteristics.

Here are some of the most popular cultivars, according to Marino. Whichever variety you choose, proper care will remain the same.

• Raven: Commonly referred to as "Raven," this ZZ plant variety's new leaves first grow in a light green hue and gradually darken to bold, nearly black foliage.
• Lucky classic: This variety has rounded leaves rather than pointy ones.
• Super nova: Similar to the raven ZZ plant variety, the super nova has very dark green, pointed leaves.
• Zenzi or dwarf ZZ: This variety is smaller and more compact with leaves that are grouped closer together.

Quick tip: The ZZ plant is considered mildly toxic to both humans and animals if ingested. This is due to the calcium oxalate, tiny crystals in the stems and leaves that can cause pain and swelling when eaten. Keep this plant on a higher shelf or stand, out of reach from small children and curious pets.

At a glance

• Botanical name: Zamioculcas zamiifolia
• Commonly known as: ZZ plant
• Hardiness zone: 9 and 10
• Toxicity: Yes (humans and pets)
• Watering frequency: Once every 2-4 weeks
• Soil type: Well-draining indoor potting mix
• Light exposure: Medium to bright indirect sunlight

Water

Overwatering is the easiest way to kill the ZZ plant, according to Marino. Only water it when the top inch or two of the soil is bone dry. This could be every few weeks, or even less frequent when it's getting lower light, such as during the winter season. When watering, Marino recommends adding tepid water directly to the potting soil.

"Do not water the plant's foliage, or directly on top of the plant," says Marino. "It's the roots, below the potting soil's surface, that you are aiming for."

Since the ZZ plant can handle dry air, Marino adds that there's no need to mist it or place it by a humidifier.

Potting and fertilizer

Marino states that any well-draining, indoor potting mix will do for the ZZ plant. You can also mix in ingredients such as perlite or lava rocks to help aerate the soil. Aeration refers to creating small holes in the soil that increases the circulation of air, water, and nutrients to the roots.

While it's not required, Marino says you can fertilize the ZZ plant about once a month during the spring-summer growing season to replenish lost nutrients from the soil. Do not fertilize during the fall and winter months, as this is when most tropical plants are semi-dormant.

Marino recommends diluting your fertilizer with water to avoid over-fertilizing, which can not only cause damage to the root system but also lead to unsightly brown or yellow spots on the leaves.

ZZ plants don't grow very quickly but can benefit from the fresh nutrients new potting soil provides. Depending on the amount of recent growth, Marino says you'll want to repot your plant about every one to two years. Ideally, you should do this in early spring, right before the growing season kicks into full gear.

If you prefer not to repot your ZZ plant, but it isn't growing in its current planter, Marino advises fertilizing it in the springtime to replenish the nutrients removed from its potting mix.

Temperature

Like most houseplants, the ZZ plant prefers a temperature range of 65 to 85 degrees Fahrenheit. Cold temperatures can stunt the plant's growth, so it's best not to let the thermostat drop below 60 degrees.

To keep the ZZ plant in its ideal temperature range, make sure to keep it away from air conditioners in the summer and heating systems during the winter, says Marino.

Light

The ZZ plant will flourish in medium to bright indirect light, but Marino adds that it's known for tolerating even extremely low levels of indirect light.

Consider placing the ZZ plant somewhere it will get 8 to 10 hours of indirect sunlight — like a bright room with south-facing windows.

Common problems

The ZZ plant is a relatively easy-going plant and generally pest-free. If you do notice pests, Marino says it's important to treat them as soon as they appear with a natural pesticide like neem oil. Spray the plant with the pesticide weekly, and regularly wipe it down with a wet cloth.

If the ZZ plant is wilting or shows wrinkled or shriveled leaves, Marino says that usually just indicates that it's thirsty and you may need to increase how frequently you're watering it.

Alternatively, if the leaves are yellowing and the soil appears wet and mushy, that may be a sign of root rot from overwatering. As long as you catch this early, you may be able to salvage the plant from root rot by pruning damaged roots and rhizomes and repotting it in fresh, dry soil. However, if all the roots look brown or black and have a slimy or mushy texture, that may indicate that they've all already rotted and cannot be revived.

Propagation

According to Marino, the easiest way to propagate a ZZ plant is by dividing up sections of the mother plant.

Once you remove the ZZ plant from its current planter, gently shake off some of the potting soil and loosen up the roots. Look for different sections of the plant that can be easily separated from one another, and then gently split them up with your hands, a sharp and clean knife, or pruners.

Make sure each sectioned-off baby plant has a healthy root system and foliage, says Marino. If the roots look white and crisp, that's a sign that they're healthy. Then, individually plant them with fresh potting mix and lightly water them.

Pruning

The ZZ plant grows relatively slowly so it doesn't need frequent pruning. However, you should trim off any lackluster yellowish or wrinkled leaves.

"Unhealthy foliage does not easily bounce back, so it's best to trim this off to help the plant conserve energy for new, healthy growth," says Marino.

Insider's takeaway

Not only is the ZZ plant an eye-catching addition to any home, it's also remarkably low-maintenance, making it perfect for forgetful owners. Since it's toxic, though, you'll want to make sure it's out of reach from children or pets.

As long as you use a quick-draining potting soil mix, water it about once a month, and make sure it gets at least low to moderate indirect sunlight, this plant should do just fine. Remember: when in doubt, underwatering is always better than overwatering, which can lead to root rot. When it's time to repot the ZZ plant, do so in the early spring and only fertilize it during the spring-summer growing season.