There's nothing better than a houseplant that offers bright, beautiful flowers in springtime. After dropping its leaves in the winter, the desert rose bonsai tree comes back with showy, beautiful flowers in shades of red, pink, and deep purple. As an indoor plant, it can be grown in a container like other houseplants or trained as a bonsai tree.
- Botanical Name: Adenium obesum
- Common Name: Desert rose, Sabi Star, desert azalea, Japanese frangipani
- Plant Type: Succulent tree
- Mature Size: Up to nine feet tall and four feet wide outdoors, two feet tall indoors
- Sun Exposure: Full sun
- Soil Type: Sandy, free-draining soil
- Soil pH: 6.0
- Toxicity: Toxic to humans, dogs, and cats
In terms of water, treat your desert rose bonsai like the succulent it is. Its bulbous stem, or caudex, holds water, so allow the soil to dry out between waterings to avoid root rot. Your plant will probably need less water during the winter months when there's less light and it's not actively growing.
Fertilize your desert rose bonsai once per month starting in spring and going through the fall. Use a standard houseplant fertilizer diluted to half strength. Stop fertilizing in the winter, when the plant goes dormant.
Best Growing Conditions for Desert Rose Bonsai
Desert rose bonsai are native to hot, dry climates, so you'll want to give them a warm, sunny place to live in your home. Its ideal temperatures range from 40 degrees at night to up to 90 degrees during the day.
A south-facing window that gets several hours of sunlight per day is an ideal spot for your desert rose bonsai. In warm and temperate climates, you can also keep your plant outside to a sunny spot with some afternoon shade from spring through fall, as long as night temperatures are warm enough. Be sure to slowly acclimate your plant to sunnier conditions in the spring, then debug your plant before bringing it back in for the winter.
A healthy, mature desert rose bonsai should bloom for several weeks in spring and summer with the right conditions. A regular fertilizing regimen in the spring and summer growing season can also help your desert rose bonsai flower. However, a recently repotted plant may divert energy away from blooming as it focuses on growing roots in its new container.
How to Propagate Desert Rose Bonsai
The best way to propagate desert rose bonsai is to take tip cuttings. Propagate your desert rose bonsai during the spring or summer for faster results.
What You Need
- Healthy, mature desert rose bonsai
- Clean, sharp shears or pruners
- Rooting hormone powder
- Small plant pot
- Rooting medium like perlite or a blend of sand and potting soil
Step 1: Select a healthy branch on the mother plant from which to take a cutting.
Step 2: Cut a six-inch long tip cutting from the end of the branch. Allow the cutting to callus over by leaving it in a shady place for a couple of days.
Step 3: When the cut has callused over, fill the container a little more than halfway with rooting medium and moisten it lightly. Wet the cut end slightly and dip it into the rooting hormone powder.
Step 4: Plant the cutting so that the cut end of the stem is just below the surface of the rooting medium.
Step 5: Keep the cutting in a place with bright light. Keep the soil just moistened, and mist the plant daily. You should begin to see new roots form in one to two months.
Common Growing Problems
Keep an eye out for pests like mealybugs, spider mites, and aphids. If you do see signs of pests, wipe them away with a cotton ball soaked in rubbing alcohol, then give the leaves a thorough spraying in the sink or shower or to remove any stragglers (cover the soil with a plastic bag to avoid overwatering).
The other issue to look out for is overwatering. If you notice the plant's leaves yellowing from the outside in and there are small spots on the caudex, cut back on watering immediately and allow the soil to dry out completely.
If you notice your desert rose's leaves turning uniformly yellow, that could be a sign that it's getting stressed by too much heat or sun. Move the plant a little further away from your light source or to a sunny spot that gets afternoon shade.
Don't be alarmed if your desert rose drops its leaves in winter—this is common in many climates. They'll grow back when the plant comes out of dormancy in the spring.
Potting and Repotting Desert Rose Bonsai
Repot your desert rose bonsai every two years or so until it's the size you prefer. Another sign that your plant needs repotting is that the caudex is crowding the pot.
It's important to wear gloves when trimming or repotting your desert rose bonsai to protect your hands from its toxic sap.
The best time of year to repot is in early spring, when the plant is actively growing. It's ideal to use a wide, shallow, bowl-shaped pot, which allows the roots to spread out and lets the soil dry more quickly.
Wait until the soil is dry to repot. Gently remove the plant from the pot and use your fingers to loosen the old soil from the roots. Cut away any rot with sterilized shears, then apply a fungicide to the cuts. Place the plant in its new container, then backfill the pot with fresh succulent soil. Wait about a week after repotting before watering.
Is Desert Rose Bonsai Toxic?
According to the ASPCA, desert rose bonsai plants are toxic to cats and dogs because they contain cardiac glycosides. They're also toxic to humans and horses.