Huernia zebrina
With spreading, spineless stems, lifesaver cactus (Huernia zebrina) is a quirky succulent.
Gracing a windowsill, trailing from a hanging basket, or serving as ground cover, the shiny red centers and tiger-striped petals of the flowers are uniquely mesmerizing!
Lifesaver cactus is an evergreen succulent that has branching, leafless stems lined with spikes.
Those spikes may look like spines, but they are not sharp to the touch, and despite its common name, H. zebrina is not a true cactus!
We link to vendors to help you find relevant products. If you buy from one of our links, we may earn a commission.
Also known as lifebuoy huernia, owl eyes, little owl eyes, and zebra-striped huernia, the stems have four to six angles, and are green, turning reddish purple when exposed to intense light or cool temperatures.
Ready to learn more about this unique succulent? Here’s what I’ll cover:
These succulent plants reach three to six inches tall and have a creeping growth habit, spreading to 12 inches wide or more.
At the base of the stems is where the intriguing flowers appear, in pairs or small clusters.
These blooms are fairly large – measuring between one and three inches wide – and are star-shaped, with yellow and red tiger stripes or mottling, and a glossy round ring at the center, inspiring the plant’s common name.
Quick Look
Common name(s): Lifesaver cactus, lifebuoy huernia, owl eyes, zebra-striped huernia
Plant type: Evergreen succulent
Hardiness (USDA Zone): 10b-11b (outdoors)
Native to: Mozambique, South Africa, Swaziland, Zimbabwe
Bloom time / season: Spring, summer
Exposure: Full sun, light shade
Soil type: Succulent/cactus growing medium, well draining
Soil pH: 6.1-7.8, slightly acidic to slightly alkaline
Time to maturity: 2-5 years
Mature size: 12 inches wide x 3-6 inches high
Best uses: Hanging baskets, houseplant, ground cover, xeriscaping
Ready for a less picturesque detail?
Since the flowers are pollinated by flies, they look – at least, glancingly – like rotting flesh.
But these flowers don’t stink, unlike those of some of the relatives of this species.
If they are pollinated, the flowers will give way to large seed pods that will ripen, dry, and split open.
The seeds have bits of fluff on them, which allows them to be dispersed by the wind.
This fascinating succulent is native to what is arguably the hotspot of succulent biodiversity in the world – the southern part of Africa, where it grows in Mozambique, South Africa, Swaziland, and Zimbabwe.
In these regions, H. zebrina populations occur among rocky limestone soils or hard loam soils in dry scrubland.
H. zebrina is classified botanically within the Apocynaceae or dogbane family, related to family members that may seem unexpected – hoyas, string of hearts, and milkweed!
Within the dogbane family, lifesaver cactus is grouped into the taxonomical subtribe Stapeliinae.
The members of this subtribe are known as stapeliads – and include other similar-looking succulents such as starfish flower (Stapelia grandiflora) and Orbea variegata.
Lifesaver cactus makes an excellent houseplant on a sunny windowsill or under a grow light.
And mature specimens can also be used as hanging and trailing succulents in hanging baskets.
You might also include it in a mixed succulent planter, or if you’re feeling rather whimsical, in a succulent fairy garden!
Outdoors in USDA Hardiness Zones 10b to 11b, lifesaver cactus can be cultivated in a container, or planted in a xeriscape as a ground cover as long as you provide excellent drainage and protection from abundant rainfall.
How to Grow
To successfully grow lifesaver cactus you’ll need to provide the right light, water, and soil.
You’ll also want to know about its temperature requirements, particularly if you are growing outdoors for part or all of the year!
Let’s start with light.
Light
Lifesaver cactus needs four to eight hours of direct sunlight to thrive.
Whether you’re growing indoors or out, that direct sun exposure should be during the morning and evening, rather than when the sun is at its hottest in the middle of the day.
If you’re keeping it outdoors for all or part of the year, be sure to choose a spot so it receives filtered light during the heat of the day.
Indoors, a south facing window is your best bet, although you may need to hang a sheer white curtain at certain times.
Are you using a grow light instead of or as a supplement to direct sun exposure? Make sure the plant is receiving at least 800 foot candles as an equivalent to that direct sun.
Not sure how to measure foot candles? Use a light meter!
Soil and Containers
Lifesaver cactus needs a somewhat gritty potting medium to provide good drainage, and it should have a pH of between 6.1 and 7.8.
When choosing a container, the first thing to look for is that it has drainage holes, a must when tending to any succulents.
These plants don’t have deep roots, so shallow succulent planters that are wider than they are deep will work perfectly, plus giving them the lateral space to expand into a clump.
For growing medium, you have options – lifesaver cactuses aren’t particularly fussy as long as they have good drainage.
You may want to make your own succulent mix, using approximately 50 percent cactus and succulent soil with roughly 50 percent additional grit such as pumice added.
I like to use Rosy Soil Cactus and Succulent mix, which is available in four-quart bags via Walmart.
Rosy Soil Cactus and Succulent Mix
If you live in a particularly arid location, you might want to skip adding extra grit to the succulent and cactus soil, since it will dry out more quickly than in regions with extra humidity.
Water
Allow the growing medium to dry fully or almost fully between waterings – there is a bit of flexibility here. If you use a moisture meter, the needle should point to the dry range.
If in doubt, err on the side of under- rather than overwatering.
When you’re ready to water, use the bottom watering technique or water the surface of the soil with a narrow spouted watering can.
If you keep your plant sitting on a saucer, make sure to empty it after watering, to avoid root rot.
Temperature and Humidity
Lifesaver cactus will thrive with humidity levels between 40 to 50 percent.
And while some gardeners claim to be able to keep these plants outdoors at temperatures down to 42°F, to be safe you should bring them indoors while temperatures are still above 50°F.
If your lifesaver cactus is exposed to temperatures around 50°F, be sure to keep the potting medium or soil dry, since cool, wet conditions can lead to rot.
Where to Buy
You can generally find lifesaver cactus available at stores that specialize in succulents or from online vendors.
Lifesaver Cactus
For example, you can purchase an H. zebrina specimen in a four-inch pot from Wekiva Garden Foliage via Amazon.
In addition to the species plant, there is a cultivated variety, H. zebrina ‘Variegata.’
With the same fascinating flowers, this cultivar has yellow and green mottled stems.
Variegated lifesaver cactus isn’t as easy to find as the species plant, so check with sellers that specialize in stapeliads if this one is on your succulent wish list.
Maintenance
If you were hoping for a low maintenance succulent, with lifesaver cactus you’ve got it!
For the most part, you won’t have to worry about removing spent foliage, as you would with echeverias.
However, do snip off spent flowers as you see them with a pair of clean, sterilized scissors or garden snips to avoid spreading disease.
Fertilizing
To provide your lifesaver cactus with nutrients, use a gentle fertilizer formulated for succulents, such as Dr. Earth’s Succulence Cactus and Succulent Plant Food.
Apply the fertilizer only during the growing season, following the manufacturer’s instructions.
Dr. Earth Succulence
Dr. Earth Succulence is available in 16-ounce pump bottles from Arbico Organics.
You can learn more about fertilizing succulents here.
Repotting
Every two to three years you’ll want to repot or at least freshen up the growing medium if the plant hasn’t outgrown its container.
If the lifesaver cactus is growing in the wrong type of growing medium, one that lacks drainage, it’s wise to switch out the growing medium immediately.
If the plant is becoming root bound, with its roots filling the pot, you should transplant to a slightly larger container, regardless of the time you last repotted.
To repot, remove the lifesaver cactus from its current container. If you are transplanting into the same type of medium that was used previously, loosen up the outer roots just a bit.
If you are switching to a different type of potting medium, remove as much of the old medium as possible from around the roots.
Place the root ball centered into the new pot, and hold the plant in place so that the surface of the soil will be about a half an inch to an inch below the rim of the container.
Then fill in around the sides of the root ball with growing medium.
Gently tamp the medium down, and wait a week before watering.
Propagation
Lifesaver cactus can be propagated from seeds or from stem cuttings.
Here’s how:
From Seed
For this project you will need some small nursery pots or a seed-starting tray, cactus and succulent growing medium, and – of course – some seeds.
- Fill your pots or seed-starting trays with growing medium, leaving a half inch to an inch gap between the surface and the rim of the pot or tray.
- Sow the seeds on the surface of the medium one to two inches apart, but don’t cover.
- Spray with a mister so that the growing medium is moist but not soggy.
- Place the pot or tray under a humidity dome. You can do this by placing a nursery pot inside a sealable plastic bag, or putting several pots or a tray into a clear plastic bin.
- Find a location in bright, indirect light, and keep them warm, between 77 to 86°F – using a heat mat if necessary.
- After the seeds germinate – within a week or two – remove the pot or tray from the heat mat, and gradually transition the seedlings to lower humidity and more intense light.
- Allow the seedlings to keep growing in the same pot or tray for a year or more, until they are too crowded and require transplanting.
Our guide to starting succulents from seed has step by step instructions.
From Stem Cuttings
The best time to propagate lifesaver cactus from stem cuttings is in spring or summer when conditions are warm.
When taking cuttings, skip the blades and simply twist branches off at the elbow.
If you have a long cutting – six inches or longer – you can cut it in half to make two cuttings, just be sure to remember which end goes up, and use clean, sterilized scissors or garden snips to cut it.
Allow the cuttings to callus over in a dry location out of direct sunlight for about a week.
The removed branches may already have aerial roots, which will help them take root when planted.
In addition to cuttings, you’ll also need growing medium and pots.
You can use a variety of pot sizes, depending on how many cuttings you have. A three-inch pot is a good size for a group of three cuttings.
When the cuttings have callused, fill the containers with potting medium until the soil is about two inches below the rim of the pot.
Starting at the center, poke holes into the medium about a half an inch or so apart, and insert the stems about an inch or so deep.
Tamp down the soil around the cuttings firmly, to help keep the stems upright.
Situate the pot in a location where the cuttings will receive bright, indirect light.
Rather than watering the cuttings right away, wait until they show signs of new growth since they don’t have roots yet.
If the branches you are planting already have aerial roots, you can go ahead and water right away.
The lifesaver cuttings should be well-rooted within a month or so. At this point, start watering as you would an adult specimen and transition the succulent to increased light exposure.
Our guide to propagating succulents has more information.
Managing Pests and Disease
The only type of insect pests you’ll have to worry about with these plants are mealybugs which are fond of feeding on their soft stems.
When you first bring your lifesaver cactus home – or before you purchase it, if possible – inspect the stems carefully for fluffy, white residue, a sign of mealybugs.
Also lift the plant out of its pot and check the roots for root mealies, a type of pest that hides in the soil, sucking nutrients from the roots.
They’ll be visible on the outer edge of the root ball if they’re present.
Whether above soil or below, mealybugs suck nutrients from plants, weakening them, and can eventually kill these plants if left untreated.
Our guide to managing mealybugs has more information about these pests.
If it’s too late and you already have an infested lifesaver plant on your hands, don’t panic!
Neem oil is quite effective at eradicating these pests as long as you are thorough and consistent with treatments.
Monterey Neem Oil
Need some neem oil? Monterey’s Neem Oil Concentrate is available in a variety of sizes via Arbico Organics.
Spray down the entire plant with neem oil, including the growing medium, diluted according to the manufacturer’s instructions.
Keep the plant out of direct sunlight for a few days following treatment as the oil can cause the plant to scorch.
Repeat treatments for six to eight weeks, and the mealies should be gone!
The main disease you’re likely to encounter is rot, as a result of overwatering, insufficient drainage, or using a poorly draining or compacted growing medium.
Learn more about how to deal with rotting succulents in our guide.
Save a Succulent Life
Remember to provide lots of direct sunlight, allow the medium to dry out between waterings, and grow in a gritty, well-draining potting medium.
Add to that some vigilance for mealybugs, and this stapeliad will produce loads of spiky stems and eye-catching flowers.
Do you have any remaining questions about growing these succulents? Or do you have any growing tips of your own you’d care to share with our readers?
Leave your questions, comments, and lifesaver cactus photos in the comments section below!
Want to keep expanding your succulent knowledge? We have more reading for you right here:
