Aloe
Family Asphodelaceae — Genus Aloe
Aloe is a large genus of over 500 species of succulent plants, most native to southern and eastern Africa, Madagascar, and the Arabian Peninsula. Best known for Aloe vera and its soothing gel, the genus encompasses an extraordinary range of forms from tiny rosettes to tree-sized specimens. Aloes combine sculptural beauty with remarkable toughness, thriving in hot, dry conditions where most other plants fail.
Quick Facts
Bloom Time
Most aloe species bloom during winter and spring, producing spectacular spikes of tubular flowers in vivid shades of red, orange, yellow, and pink. This winter-flowering habit makes aloes invaluable for providing color during the cold season in frost-free climates. The nectar-rich flowers attract hummingbirds and sunbirds.
Size and Growth Habit
Aloe ranges enormously in size. Miniature species form rosettes just 6 inches across, while tree aloes (A. barberae) can reach 30 feet or more. Most garden species grow 1 to 3 feet tall and wide, forming clumps of thick, fleshy, often toothed leaves arranged in rosettes. Many species offset freely, forming attractive colonial groups over time.
Hardiness Zones
Aloe thrives in USDA Zones 9 through 12. Most species cannot tolerate sustained frost or temperatures below 30 degrees Fahrenheit. In colder climates, grow aloe in containers that can be brought indoors for winter.
Light Requirements
Aloe grows best in full sun to partial shade. Full sun produces the most compact growth and best flowering. Some species, including Aloe vera, tolerate partial shade well. Intense afternoon sun in hot climates may cause temporary leaf discoloration.
Soil and Water Requirements
Aloe requires very well-drained, sandy or gritty soil. The fleshy leaves store water efficiently, making aloes extremely drought-tolerant. Water deeply but infrequently, allowing soil to dry completely between waterings. Overwatering is the most common cause of aloe death.
Pruning
Remove spent flower stalks at the base after bloom. Trim dead or damaged outer leaves as needed. Separate offsets (pups) from the mother plant when they are one-third her size to maintain tidy clumps or to propagate new plants.
Summer Care
Aloe is at its most vigorous in summer. Water deeply every 2 to 3 weeks in the ground; more frequently for container plants. Container aloes may need weekly watering during peak heat. Watch for sunburn on recently moved indoor plants.
Winter Care
In frost-free zones, many aloes bloom during winter. In colder climates, bring container aloes indoors to a bright window. Reduce watering to once or twice monthly. Ensure temperatures stay above 50 degrees Fahrenheit.
Companion Plants
Pests and Diseases
- Mealybugs: White cottony insects in leaf axils and on roots. Treat with rubbing alcohol or systemic insecticide.
- Scale insects: Brown bumps on leaves. Remove by hand or use horticultural oil.
- Root rot: Caused by overwatering or poor drainage. Use fast-draining soil and water sparingly.
- Aloe mite: Causes warty, cancerous growth on leaves. Remove and destroy affected tissue. No cure for severe infestations.
Common Varieties
Toxicity
Mildly toxic — use cautionWhile the inner gel of Aloe vera is widely used topically, the yellow latex (aloin) found just beneath the leaf skin is a potent laxative and can cause gastrointestinal distress if ingested. All aloe species should be considered mildly toxic to dogs and cats. The ASPCA lists aloe as toxic to pets. Keep plants out of reach of curious animals.
Care Difficulty
Aloe is one of the easiest succulents to grow. The main requirements are excellent drainage, adequate light, and restraint with watering. Container culture makes aloe accessible to gardeners in any climate.