Sedum ground cover, often called stonecrop, is a low-growing succulent prized for its dense foliage and remarkable drought tolerance. This versatile, low-maintenance plant is popular for slopes, rock gardens, or filling difficult landscape areas. Sedum thrives where many other plants fail, offering color and texture throughout the season. Successful establishment begins with careful site preparation and the correct installation method.
Site Assessment and Preparation
Identifying the proper location is the first step for planting sedum ground cover. Sedum prefers full sun, defined as at least six hours of direct sunlight daily, which promotes dense growth and abundant flowering. While creeping varieties tolerate partial shade, insufficient light causes etiolation, making the stems weak and leggy.
Sedum requires sharp drainage to prevent root rot, its most common issue. Since these succulents store water in their leaves and stems, they are ill-suited for wet or heavy clay soils. Sedum thrives in poor, lean, or rocky soil and does not require rich organic matter or frequent fertilization.
If the existing soil is heavy, amend it before planting to improve porosity. Incorporate coarse sand, fine gravel, or perlite into the top six to eight inches of soil to enhance drainage. This reduces the likelihood of standing water around the roots.
The site must be completely cleared of all weeds, especially perennial varieties, before planting. Sedum is a poor competitor during establishment, and existing weeds will quickly outcompete young plants. Removing all root fragments is necessary because once the sedum forms a dense mat, it will effectively suppress future weed growth.
Installation Methods: Step-by-Step Planting
The method for planting sedum depends on the form purchased: plugs, cuttings, or pre-vegetated mats. Planting is recommended in the spring after the last frost, allowing the plant to establish before summer heat.
Planting Plugs/Small Pots
When planting sedum plugs or small potted plants, space them appropriately to create continuous cover. Low-growing varieties are typically spaced six to twelve inches apart, depending on how quickly a solid mat is desired. Taller varieties require more space, often eighteen to twenty-four inches apart, to allow for their mature size.
Dig a hole for each plug that is roughly twice as wide as the root ball but no deeper than the container. After gently removing the plant, loosen any tightly bound roots to encourage outward growth. Place the plant into the hole, ensuring the top of the root ball is level with the surrounding soil surface.
Planting too deeply can lead to stem rot. Backfill the hole carefully with the prepared soil, firming it lightly around the base of the plant. This firm contact eliminates air pockets and allows the plant to begin absorbing water and nutrients immediately.
Planting Cuttings/Scattering
Planting sedum from cuttings is an efficient and economical way to cover a large area. Stem cuttings, usually two to five inches long, can be broadcast directly over the prepared soil surface. Ground cover sedums root easily and often have small roots already forming on the stems.
After scattering the cuttings, lightly rake them into the soil to ensure a fraction of the stem is in contact with the ground. Secure them so they are not easily displaced by wind or water, but do not bury them entirely. The stems will root wherever they touch the soil, quickly forming new plants.
For a more deliberate approach, individual cuttings can be inserted about an inch deep into the soil. This method works well for filling smaller gaps or creating a distinct pattern. Consistent soil contact is the requirement for successful rooting and establishment.
Planting Sedum Mats
Pre-vegetated sedum mats provide instant ground cover, often used for green roofs or steep slopes. The mats are typically grown on a thin coconut fiber or soil base. Installation involves unrolling the mat directly onto the prepared and leveled surface, which may include a drainage layer.
Ensure the mat has full and continuous contact with the underlying growing medium, as air pockets can cause roots to dry out. The mats can be cut easily with a utility knife to fit around obstacles or conform to edges. Pieces should be butted tightly against one another to prevent gaps and reduce the risk of edges drying out.
Essential Care for Establishment
Newly planted sedum requires consistent moisture to encourage root growth, even though it is drought-tolerant once mature. For the first two weeks following installation, water daily or nearly every day, especially during warm weather. This initial heavy watering promotes the rapid development of a strong root system.
After this period, gradually reduce the watering frequency to allow the soil to dry out between applications. This transition prevents root rot, which occurs if the soil remains waterlogged. Diligent hand-weeding is necessary until the sedum grows densely enough to suppress other plant growth.
Sedum thrives in nutrient-poor conditions, and excessive fertilizer causes weak, spindly growth. Fertilization is rarely needed. If growth is extremely slow, a very light application of a balanced, slow-release fertilizer can be applied in the spring after the roots are fully established.