Mountain aloe (Marloth’s aloe) Aloe marlothii
Mountain aloe (Marloth’s aloe) (Aloe marlothii) is an evergreen perennial shrub in the Asphodelaceae family, native to Rocky hills of north-eastern South Africa, Eswatini, Botswana, Zimbabwe and Mozambique. It grows 2–6 m (6.6–20 ft) tall and 1.2–2 m (3.9–6.6 ft) wide, wants full sun and low water, and is hardy to about -3 °C (27 °F). Space plants about 2 m (6.6 ft) apart.
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Mountain aloe (Marloth’s aloe) at a glance
| Type | Perennial shrub, evergreen |
|---|---|
| Family | Asphodelaceae |
| Mature height | 2–6 m (6.6–20 ft) |
| Mature spread | 1.2–2 m (3.9–6.6 ft) |
| Spacing | 2 m (6.6 ft) centre to centre |
| Sun | Full sun, at least 7 h of direct sun a day |
| Water | Low; drought tolerance high, waterlogging tolerance none |
| Soil pH | 5.5–8 |
| Cold hardiness | About -3 °C (27 °F) once established (roughly USDA zone 9) |
| Heat stress | Likely above about 42 °C (108 °F) |
| Flowering | about 313–521 weeks after planting, for 4–9 weeks |
| Wind tolerance | Moderate |
| Pollinator value | High |
| Edible | Not grown as food |
| Native to | Rocky hills of north-eastern South Africa, Eswatini, Botswana, Zimbabwe and Mozambique |
| Common in gardens of | 🇿🇦 South Africa, 🇺🇸 United States, 🇦🇺 Australia, 🇪🇸 Spain |
Is Mountain aloe (Marloth’s aloe) toxic?
- People: mildly toxic
- Cats: moderately toxic
- Dogs: moderately toxic
- Parts: yellow latex under the leaf skin
Aloe latex (anthraquinones such as aloin) is a strong laxative: it causes vomiting and diarrhoea in cats and dogs. The clear inner gel is much milder.
If a child or pet may have eaten part of a plant, call a poison centre or vet straight away.
Companion planting: what to grow with Mountain aloe (Marloth’s aloe)
No well-documented helpful pairing. Group it with plants that like full sun and low water.
Questions about Mountain aloe (Marloth’s aloe)
- How far apart should I plant Mountain aloe (Marloth’s aloe)?
- About 2 m (6.6 ft) apart, centre to centre. A mature plant spreads 1.2–2 m (3.9–6.6 ft).
- Does Mountain aloe (Marloth’s aloe) need full sun?
- Full sun: at least 7 hours of direct sun a day.
- How much water does Mountain aloe (Marloth’s aloe) need?
- Low water. Drought tolerance is high and waterlogging tolerance none.
- How cold-hardy is Mountain aloe (Marloth’s aloe)?
- It tolerates about -3 °C (27 °F) once established, roughly USDA zone 9.
- When does Mountain aloe (Marloth’s aloe) flower?
- About 313–521 weeks after planting, for 4–9 weeks.
- Is Mountain aloe (Marloth’s aloe) poisonous to cats and dogs?
- For cats it is moderately toxic; for dogs moderately toxic; for people mildly toxic. Aloe latex (anthraquinones such as aloin) is a strong laxative: it causes vomiting and diarrhoea in cats and dogs. The clear inner gel is much milder.
- What grows well with Mountain aloe (Marloth’s aloe)?
- There is no well-documented companion pairing for Mountain aloe (Marloth’s aloe). Group it with plants that like the same sun (full sun) and water (low).
Sources and evidence
Evidence grade A (A: strong evidence).
- Plants of the World Online (taxonomy, native range), Royal Botanic Gardens, Kew
- PlantZAfrica, South African National Biodiversity Institute
- LLIFLE Encyclopedia of Cacti and Succulents, LLIFLE (Living Encyclopedia), Italy
Notes and assumptions
- A plant of dry, sunny places: grow it in gritty, free-draining soil and water deeply but rarely; cold and wet together kill it faster than frost or drought.
- A single tall stem skirted with old dry leaves, topped by a rosette of big spiny grey leaves and, in winter, branched flower heads held almost horizontally like candelabra, in orange, yellow or red. A dramatic architectural plant in frost-free gardens.
Reference values for planning, not horticultural, veterinary or medical advice. Varieties, soils and local climates differ: check with a local nursery or extension service.
Related plants
- Daylily Hemerocallis fulva
- Red hot poker Kniphofia uvaria
- Aloe vera Aloe vera
- New Zealand flax Phormium tenax
- Quiver tree (kokerboom) Aloidendron dichotomum
- Bitter aloe (Cape aloe) Aloe ferox
- Grass tree (balga) Xanthorrhoea preissii
- Blue flax lily (paroo lily) Dianella caerulea