The largest member of the genus Tylecodon, native to the winter-rainfall belt of southern Africa from the Eastern, Western and Northern Cape into southern Namibia, all within the Succulent Karoo biome. In Afrikaans it is the botterboom ("butter tree") for its soft peeling bark. Described as Cotyledon paniculata by the younger Linnaeus and transferred to Tylecodon by Hermann Tölken in 1978, the species reaches up to 2 m with squat trunks wrapped in mustard-yellow to olive-green papery bark. It is winter-growing: leaves emerge in autumn, orange-red tubular flowers appear in early summer as the leaves drop, and the plant rests bare through the hot dry summer. For Japanese growers, surviving the humid summer is the central challenge.
Native climate
Rainfall is spread fairly evenly across the year. Overall mild, with a wide temperature range.
A broad-scale picture of the native range. Real growing spots — rock crevices, fog belts — can be milder.
Sources: climate & elevation WorldClim 2.1 (1970–2000) · occurrences GBIF · native range POWO · current weather Open-Meteo
Care
Light & Placement
The native Succulent Karoo gets ~100–200 mm of rain a year, almost all in winter, and mature plants grow in full sun on rocky slopes and coastal sands. During the autumn-to-spring growing season in Japan, give it as much direct sun as possible. The hard problem is summer placement for a winter-growing species: the priority is keeping the pot as cool and well-ventilated as possible. Move the pot to bright shade out of direct sun (north-facing eaves or 50–70% shade cloth), raise it on a bench, and run a circulation fan. Winter indoors above 5°C on a bright window is straightforward.
Watering
In autumn (September–October), once nighttime lows drop below ~20°C, restart with light watering and ramp up as leaves emerge. Through the active season, water thoroughly when the substrate has dried. Stop when leaves yellow and drop in late spring — keep essentially dry through summer. Watering in midsummer because "the soil looks dry" is the single most reliable way to kill this species.
Substrate
Drainage first, inorganic-led. Akadama : Kanuma : pumice = 3:3:4, with pumice tuned higher to dry faster. SANBI describes "a surprisingly weak and shallow root system for its size," so a shallower pot with strong airflow works as well as a deep one.
Fertilizer & Supplements
Liquid feed at double dilution once a month through the active season, or a pinch of slow-release at repotting. This is naturally slow-growing; pushing fertilizer elongates branches and dulls the bark colour.
Temperature & Overwintering
Optimal 15–25°C; above 35°C the plant slides into dormancy. Aim for a 5°C minimum — damp soil under cold is fatal. Summering this plant is harder than overwintering it: through summer, prioritize shade, ventilation and dry soil, and consider an air-conditioned room if your summers are oppressive.
Starting from Seed
Where to source seeds
Pre-sowing treatment
Soak seeds for about half a day (overnight) in a mix of a registered seed-treatment fungicide (Benlate or Daconil) and a plant tonic (Menedael; outside Japan, SUPERthrive or a chelated iron / seaweed extract works similarly), each diluted per label. Ones that stay floating are likely past their prime. The seed is extremely fine and pale brown; viability drops quickly with age.
Substrate
A separate seedling mix, fine-grained and near-sterile: fine Akadama, fine Kanuma, and vermiculite in 1:1:1, sterilized with boiling water or a microwave pass. A thin topping of coarse sand anchors the dust-fine seed (per SANBI guidance).
Sowing method
Do not cover the seeds. Sprinkle them carefully onto a pre-moistened surface. Thin clumps after germination rather than trying to space dust-fine seed perfectly.
Light & temperature
Bright shade, 15–22°C. Heating to 25–30°C disrupts germination in this winter-grower. In Japan, the standard window is autumn sowing in September through November. Germination in 1–3 weeks.
Watering
Bottom-water 1–2 cm up the pot — the seeds are too small for top-watering. Drop the water level gradually once seedlings are established.
Fertilizer
None right after germination. Once true leaves emerge, a heavily diluted liquid feed once or twice a month. SANBI records seedlings reaching only 2–3 cm in two years — no benefit to pushing the dose.
From Germination to Repotting
Germination through true leaves
Continue bottom watering, keep in bright shade.
Weaning off bottom watering
Phase out gradually over 1–2 months.
First repotting
In the first or second year, once root-bound, in autumn.
Common Pitfalls
Mold & damping-off
- Cause: excess moisture, contamination, poor airflow
- Prevention: sterilize the substrate, refresh the bottom-water, run a circulation fan
Etiolation
- Cause: insufficient light. The active winter season runs through low-sun months
- Prevention: run an LED close indoors, or move to bright shade outdoors on clear days
Seeds fail to germinate
- Cause: stale seed, temperatures too high
- Prevention: use fresh seed at room temperature (15–22°C) without a heat mat — 25–30°C actively suppresses germination
Summer stall and rot
- Cause: watering during summer dormancy, or sitting in hot, humid, poorly-ventilated spots
- Prevention: cut water once leaves yellow in late spring; through summer prioritize shade and ventilation, and consider an air-conditioned room
Notes
All Tylecodon are strongly toxic; sap contains bufadienolide cardiac glycosides (cotyledoside). Cause of the livestock disease krimpsiekte ("shrinking disease"). Wear gloves and keep away from children and pets.
