Last updated on August 25th, 2023 at 12:04 pm
Gasteria armstrongii, commonly called the cow tongue plant, Armstrong’s gasteria, succulent-leaved stone plant, dwarf succulent plant, or Flat-leaf gasteria, has an interesting appearance that makes it stand out from many other succulents. It also has very low water requirements and will not rot if kept too wet.
However, this plant does have some common issues that should be addressed to keep it healthy and happy for many years to come.
The cow tongue plant is an easy-to-grow succulent with thick, succulent leaves and bright red flowers. It can be kept in both full sun and full shade, though it does need plenty of water during the summer to stay healthy. The cow tongue plant makes an excellent choice for bonsai!
Gasteria armstrongii is one of the hardiest succulents you can grow in your home or office. Also known as the cow tongue plant because of its unusual and unique leaf shape, this gasteria makes an ideal desk-side companion! These plants grow well indoors or outdoors, with the full sun being preferred when grown indoors and partial shade when grown outdoors.
Origin and distribution
Gasteria armstrongii is a succulent-leaved stone plant that is native to South Africa. It is named after its discoverer, Fredricus Jacobus Gaster, and is commonly known as Armstrong’s Gasteria or Flat-leaf gasteria. The plant grows in rocky outcrops and has a rosette growth form.
The leaves are fleshy and have a distinctively flat shape. One of the most distinctive features of this species is the way the flowers emerge from an inflated helmet-shaped structure at the end of a long stalk. Flowers can be white, pink or greenish with a yellow throat and appear from late winter to early summer. The fruit is black and dry when ripe.
It was one of the first plants exported from southern Africa to Europe during the colonial era; it became popular among European collectors because it was one of the few new plants not found elsewhere in the world.
Gasteria armstrongii propagation
Gasteria armstrongii can be propagated by seed or division. To propagate by seed, sow the seeds in a well-drained succulent mix at the beginning of spring. To propagate by division, carefully remove offsets from the mother plant in spring or summer and pot them up in a well-drained succulent mix.
Flat-leaf gasteria can also be propagated by leaf cuttings. Cut off one of the leaves with about an inch of stem attached to it. The leaf will take root as long as it is left out in indirect light and not allowed to dry out too much.
Once it has rooted, keep it watered but not soggy wet until new growth appears. Keep it outside if night temperatures stay above 50 degrees Fahrenheit.
If night temperatures fall below 50 degrees Fahrenheit, bring the plant inside where night temperatures are maintained above 55 degrees Fahrenheit.
Gasteria armstrongii care information
Gasteria armstrongii, or Armstrong’s Gasteria, is a succulent-leaved stone plant native to South Africa. It is a member of the family Asphodelaceae, subfamily Asphodeloideae.
The flat-leaf gasteria is a slow-growing, evergreen perennial that can reach up to 60 cm in height. It has thick, dark green leaves with white spots and flowers that are borne on spikes up to 30 cm long.
Light requirement
The Gasteria armstrongii prefers bright, indirect sunlight but can also tolerate low light conditions. If the plant is placed in too much direct sunlight, the leaves will start to scorch and turn brown.
The ideal location for the Gasteria armstrongii is a bright room with plenty of indirect sunlight. One way to achieve this without over-lighting the plant is by placing it on a windowsill that receives early morning or late afternoon sun. It should not be placed directly in front of a window because this could cause overheating problems.
Soil/potting mix
Gasteria armstrongii is a succulent that grows best in well-draining soil or potting mix. The plant does not like to sit in wet soil, so make sure the mix you choose can drain quickly.
You can either purchase a succulent-specific mix at your local nursery or make your own by mixing together perlite, sand, and potting soil. Some people find it helpful to put some gravel on top of the soil before adding the other ingredients because it allows for good drainage without leaving any clumps behind.
When deciding what type of container to use for this succulent, make sure it has plenty of drainage holes. It’s also important that whatever container you use has an adequate amount of space around the sides so water doesn’t collect and rot out roots or cause them to rot from being overwatered.
Watering
Gasteria armstrongii is a drought-tolerant plant, so it doesn’t need much water. In fact, too much water can be harmful to the plant. Water only when the soil is dry to the touch. When you do water, make sure to soak the soil thoroughly. Allow the soil to dry out completely before watering again.
Fertilizer
Gasteria armstrongii is a succulent that originates from South Africa. It gets its name from the shape of its leaves, which resemble a cow’s tongue. This plant is easy to care for and is tolerant of neglect. However, it will thrive with regular fertilization. I recommend using a succulent fertilizer that is high in phosphorus.
Temperature
Gasteria armstrongii prefers warm to hot weather and can tolerate some drought. It grows best in bright, indirect light but can also tolerate some direct sun. If the temperature drops below 50 degrees Fahrenheit, the leaves will start to turn brown and wilt. The plant can recover from this if the temperature rises again, but it is best to avoid prolonged periods of cold weather.
Humidity
Gasteria armstrongii thrives in high humidity and can even tolerate full sun. The ideal humidity range is 40-60%. I would recommend placing a humidifier next to the plant to keep it happy.
Alternatively, place a container of water near the plant and mist with a spray bottle daily. It’s also helpful to have a tray filled with pebbles or rocks under the pot so that it will always be damp from condensation.
Pruning
The best time to prune your Gasteria armstrongii is in the spring, after the last frost. You’ll want to remove any dead or dying leaves, as well as any that are damaged. Be sure to also trim back any long, leggy stems. Pruning will help encourage new growth and keep your plant looking its best.
When to repot
Gasteria armstrongii, or the cow tongue plant, is a great houseplant for beginners. It’s easy to care for and doesn’t require much attention. However, you will need to repot your Gasteria armstrongii every two to three years.
In order to do this, take the plant out of its pot and place it on a towel in a spot where it can drain.
Make sure that there are no rocks or other debris on top of the soil before removing it from the pot. Then carefully remove any dead roots with your fingers or cut them off with sharp scissors.
Next, prepare a new pot by adding fresh soil. The best type of soil to use is an either sand-based or soilless mix as these types of soils will allow water to drain well and provide good drainage for the roots. Place some gravel at the bottom of the pot if you want better drainage; this should be enough to cover up half an inch on the bottom.
Fill the pot with soil and make sure not to pack it down too tightly. Once you’ve filled the pot, gently put your plant back into it, making sure not to damage any of the newly added roots. Finally, don’t forget to water your newly potted Gasteria armstrongii!
Dormancy/Winter rest
Gasteria armstrongii is a deciduous succulent, meaning that it will lose its leaves during winter dormancy. It’s important to give the plant a rest period during this time, as it will not be actively growing.
To do this, simply stop watering it and allow the soil to dry out completely. Once spring arrives, you can start watering again and the plant should start to show new growth.
Gasteria armstrongii flower & fragrance
The flowers of Gasteria armstrongii are small and tubular, and they grow in clusters. They can be white, pink, or purple, and they have a sweet fragrance. The plant blooms from spring to summer.
Growth rate
The growth rate of Gasteria armstrongii is relatively slow. In optimal conditions, it will take about two years for the plant to reach its full size. The plant prefers warm climates and does best in well-draining soil.
It is important to water the plant regularly, but be careful not to overwater it as this can lead to root rot. Gasteria armstrongii is a relatively low-maintenance plant, making it a good choice for those who are new to gardening.
Toxicity
Gasteria armstrongii is non-toxic to humans and animals, but it can cause stomach upset if ingested in large quantities. The sap of the plant is also known to be an irritant to the skin.
USDA hardiness zones
Gasteria armstrongii thrives best in USDA hardiness zones 10-11, with some varieties being able to survive up to zone 8. They are native to the Eastern Cape Province of South Africa and are a relatively easy plant to care for, thriving in a wide range of soil types and light conditions. The plant is best grown as an indoor plant since it requires protection from the hot sun.
Pests and diseases
Gasteria armstrongii is susceptible to mealybugs, scale, and spider mites. To control these pests, use insecticidal soap or neem oil. If the plant is infected with a disease, remove the affected leaves and dispose of them properly.
It may be beneficial to quarantine any new plants before introducing them into your collection, especially if you’re dealing with a stubborn infection.
