Surprisingly, what can kill a zebra plant is giving it too much of the exact things it should be getting: bright light, high humidity, and warm temperatures.
Combined, those factors create a breeding ground for fungal spores, which is what makes caring for a zebra plant that little bit trickier than most plants.
When things are off with its growing conditions, that is when problems can arise. The zebra plant can be easy to care for, but it is fussy.
When things go wrong with the growing conditions, it will look as though it is dying. It’s really just a strong cry for help to correct something that’s gone wrong.
Discover 10 Things that Can Slowly Kill a Zebra Plant
1 – Pests Can Drain the Leaves Dry
Being a tropical plant, the zebra plant is susceptible to numerous plant pests.
The usual culprits are aphids, spider mites, mealybugs, scale insects and any of the other leaf piercing species that feed on the sap from within the leaves. Although hardy to some pests, these are fast breeders that rapidly multiply once they get a start on a plant.
To get rid of bugs of houseplants or in your garden, neem oil is your friend (there’s numerous other natural ways).
2 – Being Overly Generous with Fertilizer Can Be Fatal
An excessive amount of fertilizer in the soil can be fatal to a zebra plant. They are not heavy feeders and when given too large of a dose of fertilizer, you’ll notice the leaves wilt and some will drop off.
The same reaction can happen if the plant is watered too much or not enough, so be sure that you only water when the soil is dry to the touch. Once you know that it’s not suffering from over or under watering issues, consider how much fertilizer it has been given.
A safe dosage for a zebra plant is only to feed it once per fortnight throughout the growing season, which is spring to fall. The zebra plant goes dormant in the winter. Adding more than necessary can burn the leaves.
The fix for fertilizer burn is to flush the soil of the excess salts that will have accumulated from overdoing it with fertilizer.
Do that by flooding the soil with running water, either in a sink, bathtub, the shower, or in the garden with a hose. Once it is heavily watered, allow it to sit for the water to drain freely through the drainage holes for at least a half hour. Then repeat the process a couple more times.
Each thorough watering the soil gets flushes out some salts. It needs to be done several times to rid the mix of most salts.
3 – The Soil May Have Too Little Drainage
The soil used to pot the plant has an impact on its watering requirements. The potting mix used ought to be well draining and be neutral to acidic, which is a pH range of 6.0 to 7.0.
A giveaway sign of a soil problem (either the type or the moisture content) is brown tips on a zebra plant. Spots are a sign of disease. Zebra plants with brown tips or browning at the edges are signs of water related problems and those usually tie in with the state of the soil.
As a general guide for the type of potting mix to use, it ought to have equal parts of regular potting soil, perlite, and peat moss or coconut coir.
If you are using a regular houseplant potting mix, it’s likely to need some perlite or course sand added into the mix to improve aeration.
To assist with drainage, the drainage holes in the pot should be a good size too. If there is only a minuscule hole in the pot, make it bigger for more excess water to drain.
4 – Improper Hydration
With the right potting mix used, zebra plants shouldn’t need watering more than once per week throughout the summer. It is best to let the soil remain barely moist. Never let the soil remain soggy for too long as that is what will kill a zebra plant.
Not the water itself, but the fungi growth that is encouraged when stagnant water remains in a high temperature environment with the high humidity zebra plants crave. Fungi diseases are one of the major problems that can arise when growing zebra plants (more on those to follow).
If you aren’t watering regularly and still seeing signs that your zebra plant isn’t draining water as it should, you’ll need to know how to fix an overwatered plant (and the reasons that cause it) because it numerous factors play a role in how sufficient the pot and soil drains.
5 – Exposure to Too Much Sun
Zebra plants love bright light, but overdoing it can be, surprisingly, fatal. It cannot cope in the intense heat of afternoon sun without some shade. If placing it in direct sunlight, the best spot is somewhere that benefits from a couple hours of morning sun.
For indoor plants, any window except a south facing window is ideal. If you do have to have the plant near a south facing window, it will need the sunlight to be filtered.
In direct sunlight, the leaves dry out, which prevents photosynthesis happening. When the leaves are heating to temperatures beyond what the plant can handle, you’ll see the zebra plant leaves curling in and crinkling. If the plant isn’t moved, it’s likely to lead to leaf scorch, which is when the damage really happens.
6 – Repotting at the Wrong Time of the Year
The ideal time to repot a zebra plant (or any plant for that matter) is in the spring time, just when the plant is about to come of its dormancy period. If you repot the plant in the fall, it will struggle to acclimate to the new potting mix.
The lack of sunlight, and additional fertilizer that would be added in the growing season will be lacking, causing the plant to struggle. That’s not to say that you can’t repot a zebra plant in the fall, just that it is unwise.
The problem with repotting in the fall is that it involves disturbing (and sometimes destroying) some of the plants root system. The more damage is done to the roots during the repotting process, the longer it will take the plant to recover.
You could easily find yourself nursing a zebra plant for the majority of its active growing season just to keep it alive. When that is the case, don’t go overboard with fertilizers.
Aim to get the plant plenty of sunlight, which is what will aid its recovery far better than any fertilizer. Stick with sunlight, water, and high humidity while the plant is recovering. Focus on growth once the plant is growing healthily and steadily.
As a side note, if you’ve had your zebra plant for 2+ years and never repotted it, that could be the problem. See how to fix root-bound plants because if the roots are covering the drainage holes in the pot, it will not drain water as fast as it needs to.
Fungal Diseases that Can Prove Fatal to Zebra Plants
7 – Botrytis Blight
Botrytis cinerea is the fungus responsible for what’s better known as – gray mold. The most susceptible plants to succumb to this are tropical plants requiring high humidity consistently.
When this sets in, gray mold appears on the leaf surface and can be accompanied with brown lesions on the leaf. The gray spores on the leaves are the serious problem because those are reproductive spores. They can be spread to other leaves, and other plants.
If a zebra plant gets infected with botrytis blight before it blooms, it will be unlikely to, until all of the fungus, and damaged leaves caused by it, are removed.
This really can make a zebra plant look like its days are numbered, but thankfully, its one condition that you can easily save a dying plant from succumbing to by correcting its growing climate, mainly by reducing the humidity and increasing air circulation.
8 – Fungal Leaf Spot Disease
There are two types of fungal leaf spot diseases to be aware of. Corynespora and myrothecium.
Corynespora leaf spots tend to appear on the upper leaf surface and look more like water blisters rather than spots.
The myrothecium fungus can appear on the upper and underside of leaves, appearing as concentric circles – one or more circles within a circle.
In all cases, the best bet to save a zebra plant from fungal diseases is to quarantine it from other plants and spray it with a copper fungicide.
Once you’re sure it is treated, the prevention for it is to water at the soil level. Don’t water a zebra plant from above. Let it get the water from the soil. The only moisture on the leaves should be from humidity only.
9 – Phytophthora Stem Rot
Phytophthora used to be thought of as a fungus. It’s now classified as a type of oomycete – a soil-inhabiting species that causes decay in the below-ground parts of plants. Phytophthora stem rot has no cure.
This is a disease that causes the stems to turn mushy, the leaves to diminish in greenery, and eventually dieback. Waterlogged soil is the breeding ground for Phytophthora; therefore, its presence is caused by overwatering, but keep in mind that the plant can be overwatered due to the soil or the pot not draining fast enough.
10 – Pythium Root Rot
Pythium spp. is a soil-borne pathogen that can release numerous types of spores. Similar to Phytophthora, it is caused by overly moist soil. The difference with root rot is that this can be treated – if it is caught early enough there are techniques to fix root in plants.
Damaged roots can be pruned from the plant, the entire potting mix destroyed and the plant repotted in a fresh potting mix. Preferably in a new pot in case any of the pathogens survive.
Symptoms of pythium root rot are black mushy roots. In the later stages of disease, this causes the leaves to wilt, turn yellow and eventually will kill all the leaves on a zebra plant.
Growing up with a mom who filled her home (inside and out) with all sorts of plants, Lisa got her start in gardening at a young age. Living now on her own with a home and yard full of plants (including an indoor greenhouse), she shares all the gardening tips she’s gained over the years.