Sedum

Sedum plants are hardy succulents that bring color and texture to gardens with minimal fuss. The genus includes hundreds of species that range from low creeping groundcovers to upright perennial flowers that bloom in late summer and fall.

Sedum plants belong to the Crassulaceae family and include 400 to 600 species of herbaceous perennials. Most sedums tolerate drought, heat, and cold but struggle in wet soil. The flowers bloom in shades of pink, red, white, yellow, and purple. Sedums grow well in USDA Zones 3 through 9 depending on the species.

Sedums need full sun, well-drained soil, and occasional watering once established. They work well as groundcovers, in rock gardens, on green roofs, and in containers. The plants attract pollinators and deer leave them alone.

Botanical classification and growth habits

Sedum belongs to the Crassulaceae family and includes species that vary widely in form, color, and size. The genus name comes from the Latin word “sedeo,” meaning to sit, a reference to how low-growing sedums sit and spread across the ground. Some taxonomists now place certain tall sedums in the genus Hylotelephium, but gardeners still call them sedums.

Sedums fall into two main growth categories. Low-growing sedums spread horizontally and stay under six inches tall. These mat-forming types work well as groundcovers and in rock gardens. Upright sedums grow 18 to 36 inches tall and form clumps. These taller varieties are sometimes called border sedums or showy stonecrops and work well in perennial beds.

Most sedums have fleshy succulent leaves that store water. The flowers appear in clusters at the stem tips. Low-growing types often bloom in spring or early summer with star-shaped flowers. Upright sedums bloom in late summer through fall with flat flower heads that attract butterflies and bees. Flower colors include pink, red, white, yellow, and burgundy.

Popular sedum varieties

Sedums offer hundreds of cultivars for different garden needs. ‘Autumn Joy’ is one of the most popular upright sedums. It grows 18 to 24 inches tall with pink flower heads that turn copper-red in fall. The flowers hold their shape through winter and provide structure in dormant gardens.

‘Angelina’ is a low-growing sedum with chartreuse needle-like foliage that turns golden orange in fall. It spreads quickly and tolerates foot traffic better than most sedums. ‘Dragon’s Blood’ forms a dense mat of burgundy foliage with red flowers in summer. ‘Matrona’ grows upright with purple-gray foliage and pink flowers on sturdy stems.

The Sunsparkler series includes compact upright sedums bred for color and form. ‘Dazzleberry’ has burgundy foliage with rose-pink flowers. Rock ‘N Grow series offers tough low-growing selections. ‘Bundle of Joy’ stays under four inches tall with pink flowers and works well between pavers. For more options, see this list of 20+ sedum varieties for different garden situations.

Sun and temperature requirements

Sedums need at least six hours of direct sun daily. They grow leggy and weak in shade. The plants tolerate intense heat but produce the best growth and flower color in full sun. In hot climates, afternoon shade can prevent leaf scorch.

Most sedums tolerate a wide temperature range. Hardy sedums survive winter temperatures down to -40°F (-40°C) in USDA Zone 3. They tolerate summer heat above 90°F (32°C) as long as the soil drains well. The plants go dormant in winter and return from the roots each spring. In mild climates, some low-growing sedums stay semi-evergreen through winter.

Cold-hardy upright sedums die back to the ground after frost. Leave the dried flower heads standing through winter for visual interest and to protect the crown. Cut them back in early spring before new growth starts. Tender sedums grown in containers need protection from hard freezes or can be brought indoors.

Soil requirements

Sedums need well-drained soil above all else. They rot quickly in heavy clay or soil that stays wet. Sandy or gravelly soil works well. The soil pH can be acidic, neutral, or alkaline. Sedums tolerate poor soil and do not need rich, fertile conditions.

For container-grown sedums, use a cactus and succulent potting mix or add coarse sand or perlite to regular potting soil. The mix needs to drain within seconds of watering. Heavy potting mixes hold too much moisture around the roots. Make sure containers have drainage holes.

In garden beds, work coarse sand or fine gravel into heavy soil before planting. Raised beds provide better drainage than in-ground planting in wet areas. Sedums grow well on slopes where water runs off quickly. They also thrive in rock gardens where gravel and stones keep the crown dry.

Watering needs

Water newly planted sedums weekly until established. Once the roots take hold, sedums tolerate dry soil better than wet conditions. Water established plants every two weeks during dry weather. The plants need about one inch of water per week from rain or irrigation during active growth.

Let the soil dry between waterings. Overwatering causes root rot, the most common problem with sedums. The fleshy leaves store water, so the plants survive dry spells easily. In fall and winter, reduce watering as the plants go dormant. Container sedums dry out faster than garden plants and need more frequent watering.

Watch for signs of water stress. Shriveled leaves mean the plant needs water. Soft, mushy leaves indicate too much water and possible rot. Yellow leaves can signal either problem depending on whether the soil is wet or dry.

Fertilizing and feeding

Sedums do not need fertilizer. They grow naturally in poor soil with few nutrients. Excess fertilizer, especially high-nitrogen formulas, causes weak floppy growth and reduces flowering. The plants grow better when slightly stressed.

If the soil is extremely poor, apply a light layer of compost around the plants in spring. This provides a slow nutrient release without overwhelming the plants. Avoid fresh manure or rich organic matter that holds moisture. Never use chemical fertilizers on sedums.

Container sedums may benefit from occasional feeding since nutrients leach from pots faster than garden soil. Use a diluted liquid fertilizer at quarter strength once in spring and once in midsummer. Organic fertilizer formulated for cacti and succulents works well.

Pruning and deadheading

Sedums do not need deadheading. The spent flowers add visual interest through fall and winter. For upright sedums, cut the entire plant back to ground level in early spring before new growth appears. This keeps the plants tidy and prevents the center from becoming woody.

Pinch back upright sedums in late spring or early summer to create bushier plants with more flower heads. Cut or pinch the stems back by one-third when they reach six inches tall. This delays flowering slightly but produces sturdier plants that need less staking. Stop pinching by early July to allow time for flower bud formation.

Low-growing sedums rarely need pruning. Trim back overgrown sections that spread beyond their space. Remove any dead or damaged stems as needed. The plants fill in quickly after trimming.

Planting and spacing

Plant sedums after the last spring frost when the soil warms up. Space upright sedums 12 to 18 inches apart. Low-growing sedums need 6 to 12 inches between plants depending on how quickly you want them to fill in.

Dig a hole as deep as the root ball and twice as wide. Remove the plant from its container and loosen any circling roots. Set the plant at the same depth it grew in the pot. Fill the hole with soil and water thoroughly. Mulch around the plants with gravel or small stones to keep the crown dry and suppress weeds.

For bare root sedums, plant them as soon as possible after receiving them. Spread the roots in the planting hole and cover with soil. Water well and keep the soil slightly moist until new growth appears. Bare roots establish quickly in spring through early summer.

Propagating sedums

Sedums propagate easily from stem cuttings or leaf cuttings. Take stem cuttings three to six inches long in spring or summer. Remove the lower leaves and let the cut end dry for a day. Stick the cutting in well-drained soil or sand. Water lightly and keep in bright indirect light. Roots form within two weeks.

For leaf propagation, gently twist a healthy leaf from the stem. Lay the leaf on dry soil and leave it alone. Small plantlets grow from the leaf base within a few weeks. Water sparingly once roots appear. This method works best with low-growing sedums.

Divide established sedums every three to four years to maintain vigor. Dig up the clump in spring and pull or cut it into sections. Each section needs roots and shoots. Replant the divisions at the same depth they grew before. Low-growing sedums spread by rooting along the stems, so sections can be dug and moved easily.

Container growing

Sedums grow well in containers with good drainage. Use pots with drainage holes and fill them with cactus mix or a blend of potting soil and coarse sand. Shallow wide pots work better than deep narrow ones since sedum roots stay near the surface.

Place containers in full sun. Water when the soil dries completely. Container sedums need more frequent watering than garden plants, especially in hot weather. Feed lightly once or twice during the growing season with diluted liquid fertilizer.

Repot sedums every two to three years in spring. Choose a pot one size larger if the plant has outgrown its container. Gently remove the plant and shake off old soil. Trim any dead roots. Add fresh potting mix and replant at the same depth. Water lightly and place in bright sun.

Common problems

Root rot is the main problem with sedums. It occurs when soil stays wet too long. Affected plants have soft brown stems and mushy leaves. Dig up the plant and cut away rotted sections. Let the remaining plant dry and replant in fresh well-drained soil.

Weeds compete with sedums for space and nutrients. The shallow roots of sedums make them vulnerable to being crowded out. Mulch with gravel to suppress weeds. Pull weeds by hand when they appear. Avoid deep cultivation that can damage sedum roots.

Leggy growth means the plant needs more sun or has been overfertilized. Move the plant to a sunnier spot. Pinch back stems to encourage bushier growth. Stop feeding if fertilizer was applied. Pests rarely bother sedums. Aphids occasionally appear on new growth but usually do not cause serious damage.

Garden uses

Low-growing sedums work well as groundcovers in sunny areas. They fill in quickly and tolerate some foot traffic. Plant them between stepping stones, on slopes, or in rock gardens. They grow well in shallow soil where other plants struggle.

Upright sedums fit well in perennial borders and cottage gardens. Their late-season flowers provide color when many other plants finish blooming. The sturdy flower heads attract butterflies and bees. Plant them with ornamental grasses, coneflowers, or asters for a fall display.

Sedums work on green roofs where weight and water are limited. The shallow roots and drought tolerance make them ideal for extensive green roof systems. They also grow well in living walls, hanging baskets, and vertical gardens. Mix different colored sedums for visual interest in containers or succulent gardens.