Succulents are plants that store water in specialized, thickened parts, such as their leaves, stems, or roots. This adaptation makes them exceptionally drought-tolerant, allowing them to thrive in arid environments. Succulents can be planted outside, but success depends entirely on matching the plant’s natural tolerances to your specific outdoor climate. Choosing the correct variety and properly preparing the planting site are the two most important factors for moving succulents from an indoor setting to an outdoor garden.
The Climate Factor Hardiness and Tolerance
The primary consideration for planting succulents outdoors is the local climate’s minimum winter temperature. Succulents are broadly categorized into two types: frost-hardy and frost-tender (or soft) varieties. Frost-tender succulents, which originate in regions where temperatures rarely drop below freezing, will not tolerate prolonged cold. Exposure to frost causes the water stored in their cells to freeze, resulting in irreparable damage to the plant tissue.
Frost-hardy succulents have adapted to survive in harsh, cold environments, often found in mountainous or alpine regions. These varieties can withstand temperatures well below freezing by entering a state of dormancy. In colder areas, tender succulents must be treated as annuals or relocated indoors for winter. Understanding your region’s average minimum winter temperature is the most important step in deciding which succulents to plant outside year-round.
Essential Requirements for Outdoor Success
Beyond temperature tolerance, the physical environment must be prepared to meet the unique needs of succulents. The most important requirement is excellent drainage, as succulents are highly susceptible to root rot if their roots remain in saturated soil. Standard garden soil is inadequate because it retains too much moisture. To ensure rapid drainage, the soil needs to be amended significantly with porous, mineral-based materials.
A suitable outdoor mix often consists of one part organic matter to three parts mineral content. Recommended amendments to native soil include:
- Coarse grit
- Pumice
- Coarse sand
- Horticultural lava
These materials create air pockets and allow water to move quickly away from the roots. For in-ground planting, creating a slightly elevated or sloped bed can further enhance drainage. Succulents generally thrive in full sun, but excessive midday sun in hot climates can cause leaf sunburn, appearing as white, brown, or black patches. In hot conditions, a location that receives morning sun and some afternoon shade is optimal to prevent sunscald.
Choosing the Right Succulents
Selecting the appropriate species is key to long-term success in an outdoor garden. Hardy succulents are the only choice for gardeners in regions with cold winters. The two most common groups of frost-hardy succulents are Sempervivum (Hens and Chicks) and the frost-tolerant subset of Sedum (Stonecrop). Sempervivum forms tight rosettes, while Sedum varieties are known for their dense, mat-forming or upright habits.
In contrast, soft or tender succulents are suited only for year-round outdoor planting in warm climates where frost is absent. These varieties, prized for their vibrant colors and striking shapes, include popular genera like:
- Echeveria
- Crassula (Jade Plant)
- Aeonium
- Kalanchoe
In cooler areas, these tender plants must be grown in containers so they can be easily moved indoors before the first expected frost. Careful selection based on the plant’s genetic hardiness prevents the inevitable loss of cold-sensitive varieties when winter arrives.
Seasonal Care and Protection
Once succulents are established outdoors, their care routine adjusts with the changing seasons. During the active growing period in spring and summer, outdoor succulents require deep, infrequent watering. In-ground plants generally need water only every 10 days to two weeks, allowing the soil to dry completely between applications to prevent root rot. Watering frequency must be reduced significantly during the cooler fall and winter months, as plants enter dormancy and saturated soil makes them vulnerable to frost damage.
When cold temperatures are expected, frost-tender varieties must be brought inside to a sunny location or under grow lights. For hardy varieties left outdoors, winter protection can include adding a layer of bark or hay mulch around the root zone for insulation. Keeping the crown clear of debris and excessive moisture is important year-round, as a wet base increases the risk of rot and attracts pests. Checking for common outdoor pests, such as spider mites or mealy bugs, should be a routine part of seasonal maintenance.