What’s Wrong With My ZZ Plant? 5 Problems and Fixes

ZZ plants are the epitome of low maintenance. Their easy care, coupled with architectural foliage, makes them a popular houseplant across styles. Glossy leaflets line sturdy, gently arching stems in olive, onyx, and variegated.

While adaptable houseplants, temperature changes, lighting, or water issues are common stressors. Acclimating to fluctuations in their growing environment, too, may create physical markers. With a few adjustments, the structural tropical often rebounds to its easy-care state. Many of us have ZZ revival stories, and yours may be one of them!

Here are the most common problems you may face with ZZ plants in your home.

Pale Leaflets

Zamioculcas zamiifolia has long-stemmed leaves, each lined with shiny, symmetrical leaflets. Depending on the variety they’re deep green, purple-black, or with creamy gold variegated patches.

Leaf pallor is a common response to certain growing conditions. Too much or too little sunlight and watering issues are the most common causes, where leaflets lose their luster and richness.

Sun Exposure

In nature, ZZ experiences a range of light exposures, from southern African tropical forest understories to grassy savannahs. In more temperate climates and indoors, their best light is bright and indirect. They even grow solely in fluorescent lighting, though low light conditions mean slower growth. Low light also affects leaf pigment. 

Certain varieties like ‘Raven’ in black plum and those with variegation show the most color in bright, indirect light. Green varieties tolerate lower light conditions, with plenty of chlorophyll for photosynthesizing across conditions.

Too much sunlight, too, causes leaves to fade or turn brown. Direct rays sunburn the leaflets, and the scorch damages their tissues. Position them with a few hours of morning sun exposure and protection from afternoon sun in dappled light or high shade. Indoors, situate them near a bright window but out of the direct sun, or filter it with a curtain. Turn the pots periodically for even exposure.

Wilted Leaves

Wilted leaves on ZZ plants most often indicate watering problems—too much or too little—followed by too much sun or low humidity. In their native forests, roots don’t sit for prolonged periods in wet soils. ZZ plants are aroids (like peace lilies and philodendrons) with thick rhizomes that store water.

These rhizomes make them drought-tolerant with succulent and cacti qualities. Waxy leaves help prevent water loss in addition to their glossy appeal. These physiological attributes allow us to go away for weeks at a time and return to a perfectly healthy ZZ.

But they benefit from regular moisture. A thorough watering followed by a slight drying-out period is best. A good rule of thumb is to water thoroughly when potting media feels dry one inch below the surface. A well-draining potting mix is essential.

Watering

In summer, ZZ takes watering every week or two, allowing soils to dry a bit between sessions. In winter, when growth slows, reduce watering to about once a month to prevent overwatering. Continue to gauge the timing by feeling the soil surface for dryness.

If you notice persistent moisture coupled with weak stems, yellowing leaflets, and a lack of vigor, check for overwatering. A pot that’s too large may also be the culprit. Excess soil volume without root mass holds water around the roots. Transfer the ZZ to a smaller, more fitting vessel.

Root Rot

Overwatering damages roots and leads to their inability to uptake moisture and nutrients. Root rot is a fungal disease that pops up during prolonged saturation. Rot causes the roots to turn brown and mushy. As they decay, they can’t function to support growth.

ZZ in overly soggy media with poor airflow may show yellowing and wilting leaves. Inspect the rhizomes and cut away any brown, damaged portions.

Replant in fresh potting media and water thoroughly to initiate a new regimen. If caught early, you may see growth revive. Since ZZ propagates easily from leaf cuttings, it may be wise to take a few in case the roots can’t recover.

Turning Yellow or Brown

Yellowing leaves are signs of stress and often reflect over or underwatering. Underwatering may also present as withered leaflets and limp stems. Correct watering issues by allowing the soil to dry slightly and getting on track with a consistent schedule based on the soil surface feeling somewhat dry.

Less often for ZZ, yellowing may indicate a nutrient deficiency. A lack of nutrition may result from an aged potting mix or a need for fertilizer.

Brown stems indicate a problem is well underway, but it may be reversible. Cut off any brown sections to a healthy part of the stem. Investigate the soil and roots to determine if the browning is a response to watering or potentially another cause. Water inconsistencies eventually cause browning and dieback.

Too much sunlight, too, can cause browning. Direct rays sunburn the leaves and scorch their tissues.

Fertilizer

If you suspect nutrient deficiency, a balanced fertilizer during the active growing season (warm months) gives a boost. Apply a houseplant formula once or twice a year – the rugged growers don’t need much. Every few years, refresh the potting media by repotting the ZZ in the same or a larger container.

Leaf Drop

Like yellowing or wilting leaflets, leaf drop indicates several possible underlying causes. First, check all the primary growing conditions, particularly water, sunlight, and temperature. ZZ likes moderate temperatures between 65°F and 75°F (18-24°C).

Then, scout for pests. While not usually a problem for ZZ plants, scale, mealybugs, and spider mites are common in houseplants and may take hold.

Pests

Mealybugs are soft-bodied and look like tiny tufts of white cotton. Infestations are visible by the insects themselves and by yellowing, wilting, or stunted leaves. They gravitate toward specimens stressed by under or overwatering. 

To mitigate small populations, run stems under a strong stream of water to displace the insects. Then, dab any remaining with a cotton swap soaked in isopropyl alcohol – immediately effective. Insecticidal soaps and horticultural oils offer more potent treatments and may need repeated applications in severe cases.

Scale, too, pierce leaves and stems to feed on sap. You may notice a sticky honeydew residue in their wake. The small insects usually appear on the undersides of leaves as black, gray, or silvery dots. Leaflets may yellow and drop, dying back in heavy infestations. Remove affected stems to an area of healthy growth.

Spider mites are common in houseplants and live on the undersides of leaves, showing up as webbing and light yellowing of leaf surfaces. The tiny pests are difficult to see without a microscope but stippled and bronzey, papery leaves or webbing are indicators.

Scale, mealybugs, and spider mites gravitate toward specimens stressed by under or overwatering. They flock to dusty leaves, too, so give ZZ an occasional rinse.

Weak Stems and Exposed Roots

Weak, languid stems are common problems associated with under and overwatering ZZ plants, but they may also indicate a need to repot. Relatively slow-growing, ZZ likes to be snug in a container to produce new shoots. It doesn’t need repotting often, and every few years is usually sufficient.

But, cramped rhizomes eventually exhibit signs in the leafy upper growth. As roots aren’t able to hold enough moisture or nutrients, stems may become weak and limp. Crowded conditions can also present as yellow or wilted leaves. Often, water will quickly run through drainage holes as it passes over the rhizomes with little media to absorb moisture.

The tell-tale sign that a specimen needs repotting is exposed rhizomes. You’ll see them popping out of the drainage holes or above the soil surface as they seek more space. Within the soil, they may show circling or entangling, especially at the base.

As potting mix ages with continual watering and nutrient uptake by the plant, it begins to collapse. Compaction and a lack of aeration lead to stress, including oversaturation. If the ZZ is in the same pot for a few years, give it a fresh mix, even if returning it to the same container after cleaning up roots and replacing new media.

Repotting

If signs point toward repotting, move the houseplants to a larger one during the active growth in the spring or summer. Choose a container one to two times larger than the current one with ample drainage holes.