Aloe is a genus of plants in the Asphodelaceae family, including more than five hundred perennial succulents.
Of these flowering herbs, the one we know most of is the Aloe vera plant; indeed, many Aloe family members are mistakenly identified as Aloe vera.
One member of this genus that is unlikely to be misidentified in this way is bright and bristly Aloe dorotheae (AL-oh, dor-uh-THEE-ay), the Sunset Aloe.
This colorful ornamental succulent is also known as:
- Tanzanian Aloe
- Crimson Aloe
- Aloe harmsii
- Karoo Aloe
This native Tanzanian plant’s botanical name honors Dr. Dorothea Christina van Huyssteen, the daughter of D.P van Huyssteen, an esteemed collector of succulent plants in South Africa.
It is worth noting that the Aloe bussei is also a Tanzanian native Aloe that is quite similar to Aloe dorotheae in appearance. You can tell it apart from Sunset Aloe because A. bussei has very simple pink blooms, and its marginal teeth are a bit flexible.
Aloe harmsii is a variation of Aloe dorotheae. This is the variety that bears yellow blooms.
All three of these varieties (A. dorotheae, A. bussei and A. harmsii)were identified and described by German botanist, Alwin Berger in 1908. You may occasionally hear Sunset Aloe referred to as Aloe dorotheae A. Berger.
This unusual Aloe is listed as critically endangered in its native Eastern Africa and Tanzania, so cultivating it as a houseplant or a garden plant in conducive settings can be a good deed and a pleasure.
- Aloe Dorotheae Care
- How To Propagate Crimson Aloe
- Tanzanian Aloe Main Pest or Diseases
- Suggested Sunset Aloe Dorotheae Uses
- Save A Sunset Aloe And Brighten Your Home!
In this article, we discuss the Tanzanian Aloe and provide good advice on caring for and propagating it. Read on to learn more.
Aloe Dorotheae Care
Easy Guide to Growing: Aloe Dorotheae (Sunset Aloe)
Size and Growth
Sunset Aloe has a low growth habit and typically attains a height of about 8” to 12” inches.
The rosettes grow from short, inconspicuous stems that tend to sprawl and allow the rosette clumps to spread.
This shrubby, rosette-forming succulent spreads slowly and may eventually form clumps that are as great as twenty inches across.
Flowering and Fragrance
Aloe dorotheae has salmon, orange, or red flowers. The variant Aloe harmsii has bright yellow and green tubular flowers.
The flowers are borne atop 2-foot-high spikes. Each flower spike produces a generous number of blooms.
The spikes typically appear mid-autumn, and the showy flowers bloom in winter.
The fragrant flowers are attractive to pollinators of all sorts.
Aloe Dorotheae (Sunset Aloe)
Karoo Aloe’s plump, tapering, lance-shaped leaves are slightly curved when the plant is well cared for. During times of extreme drought, they tend to curl in on themselves.
The leaves are glossy and often described as having an artificial or plastic appearance. The margins of the leaves bear rows of white, spiky teeth.
Young plants’ leaves are freckled with elongated white blotches. As the plant matures, the freckles fade, and the blush develops.
The more sun Sunset Aloe receives, the deeper the blush. The plants’ brightly colored leaves may be orange, red, or scarlet with coppery glints.
It’s important to understand that this coloration may also be a stress response. The leaves will turn very deep red during times of drought. If you note that the leaves are also curling in upon themselves, take this as a sign that your plant needs deep watering.
Light and Temperature
Although this plant can tolerate full sun, a little protection against extremes is beneficial. In consistently warm areas that do not have harshly punishing sun, Crimson Aloe grows well in full sun.
Protection from very harsh noonday and afternoon sun is desirable in desert-like settings.
Indoors, ample bright, indirect light is preferable to direct light amplified through the glass. Place your Ramenas Aloe near a sunny window, but don’t let it get a chill through the windowpane.
This plant is not frost tolerant. Ramenas Aloe can handle a little bit of chill, but for the most part, it does best with hot summers, warm autumns, and balmy winters.
Tanzanian Aloes’ mountainous South African home has a consistently warm climate, with 80° and 90° degrees Fahrenheit temperatures.
This plant does best with this sort of consistent warmth, but it can tolerate brief temperature dips as low as 40° degrees Fahrenheit.
Karoo Aloe can successfully grow outdoors in USDA hardiness zones 10 and higher. Below USDA hardiness zone 10, it’s best to keep your Sunset Aloe as a houseplant during the cold months. It is unhappy and will not thrive at temperatures below 50° degrees Fahrenheit.
The ideal temperature range is 55° to 85° degrees Fahrenheit. Your houseplant will enjoy time spent outdoors during the warm months of spring and summer.
Be sure to transition it gradually and carefully from indoors to outdoors. Protect it against dramatic temperature changes, harsh sunlight, and high winds.
Watering and Feeding
Crimson Aloe is quite drought tolerant, and it is an easy care plant for forgetful pet parents who might be a bit haphazard about watering.
Like most plants, the Sunset Aloe is far happier with too little watering than with too much. Overwatering can cause problems with fungal infections, such as root rot.
Establishing a soak-and-dry watering practice is best to allow the plant’s soil to dry. As with most succulents, you may even want to wait until the leaves show signs of stress by wilting or turning in upon themselves.
When this happens, you know your Aloe needs a thorough watering. You can either pour water through the plants’ substrate until it runs through the drainage holes in the bottom of the pot or set it in a water container and allow it to soak up moisture from below.
If you choose to bottom-water, set a timer for 15 minutes. Don’t allow your plant to stand in water for long periods because this can lead to root rot.
Generally speaking, deep weekly watering is enough for most houseplants but observe your plant carefully for signs that it needs water. If the soil is still a bit moist and/or the leaves are very plump, hold off for a day or two.
In the landscape, Karoo Aloe can usually do well with natural rainfall, except in very harsh desert settings or during extreme drought. In this case, provide a deep weekly watering.
Use a soaker hose or place your hose on the ground and let the water trickle around the plants for a long time.
Avoid overhead watering, as this can lead to leaf spotting and fungal infection of the leaves.
Although Sunset Aloe is drought tolerant, it will perform better and flower more with regular watering during the spring and summer months.
Typically, it is wise to water weekly in the spring and summer, monthly in the autumn, and not at all in the very coldest months of the year (typically December and January.)
Generally speaking, you should reduce or stop watering during cool weather, but this isn’t always true. You’ll need to evaluate your plants’ need for water in wintertime on a case-by-case basis.
In areas with very warm, dry winters, you may need to keep watering as usual or reduce watering only slightly.
Indoors, if your ambient temperature is high and the air is quite dry, you may need to continue watering as usual, and you may need to add a humidifier to help moisten the air.
Feed Your Sunset Aloe Sparingly
As with most succulents, Aloe dorotheae is not a hungry plant. You may not need to fertilize if you repot container plants annually using a good cactus or succulent mix.
If you repot less frequently, or if your plants are in the landscape, fertilize once in the early spring and again in midsummer using a specially formulated, balanced, water-soluble succulent fertilizer with an NPK ratio of 10-10-10.
Soil and Transplanting
As with most succulents, Crimson Aloe prefers sharply-draining soil. It can do quite well in very poor soil in the landscape, but it does need excellent drainage.
The best soil is a high-quality mix with plenty of loam and coarse sand. You can use a commercially prepared cactus or succulent mix or make your own mixture consisting of half coarse sand and a quarter each of good quality potting soil and organic matter such as aged compost.
This mixture will give your plant all the nutrients it needs for the first year. Remember to fertilize as described above if you do not repot in subsequent years.
Should you repot your Sunset Aloe every spring?
Frequent repotting is unnecessary, and it is better to wait until the Sunset Aloe has spread and is quite crowded in its pot before giving it a new home.
When this happens, schedule your repotting for early spring when the plant is in active growth.
The best sort of container for this dense, spreading, low-growing succulent is a hefty (3+ gallon) shallow terra cotta pot with ample drainage holes.
Grooming and Maintenance
Aloe dorotheae doesn’t need regular pruning. Of course, you should remove any damaged, diseased or dead leaves as they appear.
As your Sunset Aloe strives to spread, it may get a little leggy. When this happens, you can trim off the wandering rosettes. Be sure to save them to grow more plants.
By the same token, when the plant produces pups, you may occasionally wish to remove them for the plant’s appearance. When you do, you can simply pop them into their own pots.
How To Propagate Crimson Aloe
Crimson Aloe can be grown from seed, but the easiest way to propagate it is to separate pups, plant them, and treat them as mature plants.
If your plant gets leggy with lots of dangling rosettes, you can propagate by stem cuttings. Be sure there is a root node on the cutting. Cut it away cleanly with a sharp, sterilized cutting implement.
Allow the cutting to air for a few hours, then pot it in a slightly moist potting mix. Another way to do this is to pot it into a dry or nearly dry mix and then wait a few days before giving it a moderate watering. As with most succulents, you can immediately treat the cutting as a mature plant.
You can also divide the plants at the time of repotting. If you don’t have a parent plant, you can order seed online and sow it on the surface of sandy soil in autumn.
Choose a sheltered setting that receives bright, indirect sunlight and maintains consistent temperatures of 68° to 75° degrees Fahrenheit.
Keep the soil consistently moist (not soggy). You should see germination within a couple of weeks.
Tanzanian Aloe Main Pest or Diseases
Aloe plants are generally fairly pest and disease free as long as they are kept warm, not overwatered, and get ample sunlight.
Plants that are kept in less-than-ideal conditions may be subject to infestation by the usual houseplant pest culprits, such as:
- Scale Insects
Generally speaking, all of these pests can be dealt with by rinsing them off the plant with a strong spray of water and following up with insecticidal soap or neem oil spray treatment.
Scale insects may be a little bit difficult to remove. You may need to scrape them off with a dull knife blade or your thumbnail.
Can you give Sunset Aloe too much water and fertilizer?
Overwatered plants or those kept in dark, damp conditions are subject to fungal infections, such as leaf, stem, and root rot. Always err on the side of caution when watering, and don’t mist these plants or any other succulents.
Too much fertilizer can cause leaf browning and weakened plants that grow too rapidly and topple. When this happens, prune your plant and repot it into fresh soil.
Is the plant considered toxic or poisonous to people, kids, and pets?
Aloe dorotheae is entirely non-toxic to people, pets, and livestock; however, be careful of its rather aggressive prickles, thorns, and spines.
Is the plant considered invasive?
In the wild, there are only a couple of areas in Tanzania’s Eastern Arc Mountains where this plant grows naturally.
Because it has been aggressively collected for many years, it has been red-listed as critically endangered by the International Union for Conservation of Nature (IUCN).
Although collection and limited distribution have caused the plant to become endangered, it is fortunate that many examples of Sunset Aloe do exist thanks to its easy-care growth habits and enthusiastic domestic cultivation.
Suggested Sunset Aloe Dorotheae Uses
Sunset Aloe is a wonderful ornamental succulent admired for its blooms as much as its colorful foliage. It can make a dramatic ground cover or specimen plant in a warm climate.
It is pretty in a rock garden and a great addition to a Xeriscape, desert bird, or pollinator garden. Birds of all sorts are naturally attracted to these pretty plants. Hummingbirds especially like the nectar of the blooms.
As a container plant, Crimson Aloe makes a colorful front porch, patio, or terrace addition. Imaginative and artistic gardeners can use the plant in decorative containers, Mediterranean gardens, and undersea-themed gardens.
If you live in an area with a very mild climate, your Tanzanian Aloe will do well in a hot, dry outdoor setting such as a rock garden that mimics its African desert home.
Save A Sunset Aloe And Brighten Your Home!
Aloe dorotheae is a beautiful plant that is rapidly losing its natural habitat. Luckily, if you can provide it with some basic care, you can help this colorful succulent survive as a species.
Remember that these plants enjoy a desert-like setting with bright light, occasional deep watering, and a coarse substrate allowing excess water to drain quickly.
If you have a place in your home or garden that can provide your plant with a minimum of 6 hours of bright sunlight daily, consistently warm temperatures, and moderate humidity, you can give this pretty plant a home.