The Burro’s Tail (Sedum morganianum) is a stunning succulent celebrated for its distinctive, trailing stems densely covered in plump, bead-like leaves. This cascading growth habit makes it highly sought-after, especially in hanging containers. The possibility of growing this tropical succulent outdoors year-round depends entirely on the specific climate, as it tolerates only a narrow range of conditions.
Climate and Hardiness Zones
The core limitation for permanently growing Burro’s Tail outdoors is its extreme sensitivity to cold temperatures and frost. Originating from southern Mexico and Honduras, the plant is not equipped to handle freezing conditions. Frost is lethal, causing the water-filled leaves to rupture and leading to the plant’s death.
This succulent prefers temperatures to remain above 50°F (10°C) for optimal health and growth. While it can tolerate brief, non-freezing dips down to about 40°F (4.5°C), prolonged exposure to anything near this threshold will cause damage. The concept of USDA Hardiness Zones is used to map areas where a plant can survive the average minimum winter temperature.
Consequently, permanent outdoor cultivation is generally restricted to USDA Hardiness Zones 10 and 11. Areas in Zone 9, particularly 9b, may allow year-round outdoor growth, but only if the location is sheltered and free from any risk of frost. In any zone colder than 9, the plant must be considered a seasonal outdoor accent or a container plant that is brought inside for the winter.
Meeting Light and Soil Needs Outdoors
Assuming the local climate is warm enough, providing the correct light and soil conditions is the next requirement for outdoor success. The Burro’s Tail thrives in bright light, often preferring full morning sun. However, in hotter climates, protection from intense afternoon sun is necessary to prevent the leaves from getting sunburned.
An ideal outdoor location is a spot with morning sun and afternoon shade, such as under a covered patio or a partially shaded eave. If the plant does not receive enough light, its stems will stretch out in a process called etiolation, resulting in a sparse, less attractive appearance. The plump leaves also rely on sufficient light to maintain their compact, dense growth habit.
The soil requirements outdoors demand exceptional drainage to prevent root rot, which is the most common killer of this succulent. Native garden soil is typically too dense, retaining too much moisture, especially after rain. For in-ground planting, the soil must be heavily amended with coarse materials like perlite, pumice, or grit to ensure fast water runoff.
A more reliable method for outdoor growing, even in suitable zones, is planting in containers or raised beds using a specialized cactus or succulent potting mix. This approach allows for complete control over the soil composition and ensures that excess water drains away freely. Because the plant’s fleshy leaves store water, it is highly susceptible to overwatering and high humidity.
Acclimation and Winterization Tactics
For gardeners in marginal zones, where temperatures occasionally dip toward the danger zone, a two-part strategy involving seasonal movement is necessary. The first tactic is acclimation, or “hardening off,” which prepares an indoor-grown plant for stronger, direct light outdoors. This involves gradually introducing the succulent to increasing amounts of direct sun over about two weeks to prevent leaf scorch.
Starting with a few hours of morning sun and slowly increasing the exposure allows the plant to adjust its tissues to higher UV levels. Moving a plant directly from a sheltered indoor environment to harsh outdoor light can severely damage the foliage. Once hardened, the Burro’s Tail can enjoy its outdoor location for the entire warm season.
The second tactic is winterization, which involves protecting the plant from cold snaps. In Zone 9, where brief cold periods are possible, an outdoor plant can be temporarily covered with frost cloth or moved to a cold frame. In colder zones, the plant must be brought indoors entirely before nighttime temperatures consistently fall below 50°F (10°C). Containers should be placed in a bright, cool indoor location, and watering should be significantly reduced during this dormant period.