Sedum plants bring a host of variety, charm and longevity to any ornamental display. Small, sun-loving and easy to grow, the stonecrop (as it is also known) is a drought-tolerant hardy perennial that works equally well as ground cover and in rock garden arrangements.
Upright or floppy stems often sprout from a tight crown and carry distinctive succulent foliage. The fleshy leaves vary in shape from slender and almost cylindrical through cupped to flattened in shape. In color, the range runs from bright chartreuse and blue-green to magenta and deep purple. There are also some dramatic variegated varieties available.
It's worth learning how to grow sedums as they work just as well in modest flower beds as the most ambitious, since they rarely exceed 2ft (60cm) in height. The shortest varieties are mainly spring flowering, with the taller types flowering in summer and fall and sometimes collapsing, especially after heavy rain. Flowers are mainly red, pink or white, with a few yellow flowered varieties. In many, the flowers progress through an intriguing series of color changes, and some later-flowering varieties turn straw brown late in the season.
The individual flowers are small and star-shaped, gathered into conical, domed or flat-topped clusters at the tips of the shoots. These are dynamic and can be as broad as 9in (23cm) across.
Not only are sedums some of the best ground cover plants, they are also excellent plants to grow if you are looking to attract pollinators to your plot. The blooms are popular with butterflies and bees, and the flower heads are often crowded with visiting winged insects.
Hylotelephium cauticola ‘Lidakense’ is a low-growing succulent ideal for walls and containers
Sedum plants: key facts
- Plant type: Fruiting tree
- Mature size: 20-30ft (7-9m)
- Soil type: Fertile, moist, well-drained
- Soil PH: Slightly acidic to neutral
- Time of year to plant: Fall
- Flowering time of year: Spring
- Flower color: Maroon
- Hardiness zones: USDA 5-9
- Scientific name: Asimina triloba
- Common name: Pawpaw, custard apple, Indiana banana, wild banana
How many types of sedum are there?
Sedums can be divided into two groups: rock garden varieties and hardy perennial flower garden types. There is some overlap between the two groups, but generally they are distinct and should be grown accordingly.
Part of the appeal of this brilliant drought tolerant plant lies in its hardy nature. 'These plants withstand drought, frosts, poor soil, full sun and high temperatures, and still reward you with stunning colors and blooms,' say the experts at Mountain Crest Gardens.
As long as you are clear about where you wish to plant your stonecrops, it will be easy to decide which type to choose.
- Rock garden sedums The smaller varieties of sedum are ideal plants for modern rock gardens, gravel gardens, drought gardens, raised beds, green roofs, troughs and as specimens in small pots. Some, including ‘Angelina’, spread quickly and make attractive low maintenance ground cover plants. Others, like ‘Ruby Glow’, develop a tight crown with floppy stems. Many of these rock garden types root where the stems touch the ground or from broken pieces of stem.
- Flower garden sedums Hardy perennial flower garden types are derived from two species, Sedum spectabile and Sedum telephium. These are indispensable plants for late summer and fall color, and essential plants for pollinators, providing nectar for late season insects. The clumps can become so crowded with flower stems that they lean outwards and may need support.
Scientists have been looking closely at sedums in recent years, and have decided that some are so different they require different names. So although many rock garden types are still called sedums, most hardy perennial flower garden types are now called Hylotelephium.
Evergreen, mat-forming Sedum rupestre ‘Angelina’ has yellow flowers in summer
When and where to plant sedum
Sedums enjoy full sunshine and are ideal plants for rockeries. In the northern hemisphere they do best in a west- or south-facing garden or a sunny border. Shady or covered spots may cause problems: when they are planted under trees, sedums can become thin and spindly, dark-leaved varieties lose coloring in stems and leaves, and flower heads become small. However, sedums are not fussy: these plants appreciate low-maintenance patio arrangements and they are happy growing around pathways and filling out in quiet corners.
These plants can also work well in vertical garden ideas that incorporate walls and rocks. They like to clamber up stone walls. But again, just think about exposure to sunshine. Plants shaded from the side, in the shadow of a fence or wall – where the plants are in good light but not in the sun – will not thrive in the same way as those in full sun. Also, plants tend to do best if planted in the spring or in the fall.
Rock garden sedums such as compact ‘Lidakense’, with its purple-tinted blue-green leaves and pink flowers, work well in terracotta pots, garden planters and troughs, as well as raised garden beds. The more vigorous ‘Angelina’, with its slender chartreuse foliage and yellow flowers, is good for low ground cover in a gravel garden and works well for xeriscaping.
Choose taller sedum varieties for mixed or perennial plantings, flower gardens and pollinator plantings. Try ‘Autumn Joy’ (‘Herbstfreude’) with its pink flowers, or ‘Red Cauli’ with its deep foliage and bright blooms. This type does well with the fluffier growth of perennial asters. And the SunSparkler Series, with its long season of dynamic foliage and flower tones, is ideal where you need neat plants to give months of color.
Sedums thrive in full sun and are often spotted scrambling up walls and terraces as well as rockeries, pots and borders
How to plant sedum
Good drainage is critical when planting sedums. Whether you are looking to add some stonecrops to sunny garden borders or inventive container gardening ideas, make sure the roots of these plants aren’t exposed to extended periods of excess moisture. In heavy clay soils or waterlogged conditions, the roots and crowns of sedum plants tend to rot. Adding gravel to improve drainage can help, but in moist conditions it is wiser to choose from the many plants that enjoy damp soil.
'Virtually all sedums require a well-drained site, and soil of low to moderate fertility is preferable,' says the American Horticultural Society. Sandy or gravelly soil is preferred for sedum planting. If you are unsure about the level of drainage in your soil, you could try adding a little sand or gravel to your existing beds and borders to guarantee better results.
Unlike many plants, sedums are unhappy in rich, fertile soil and when overfed. These conditions encourage soft and leafy stems that collapse under the weight of flowers or in a rainstorm. Soil that is too rich also seems to encourage mildew. So if in doubt, err on the side of ‘cruel to be kind’ and you won’t go too far wrong when planting stonecrops.
No special planting technique is necessary with sedums, although it is important not to plant too shallowly or too deeply. Setting the crown a little below the soil level is best. If you are looking to plant bare-root plants, be sure to encourage the soil to filter in among the roots.
Sedum plants enjoy free-draining conditions and are ideal for gravel gardens
Sedum care tips
Stonecrops are relatively low maintenance so you don’t need to give them much attention. Just a few sedum care tips here and there will ensure healthy, prolific growth year after year.
Rock garden sedums appreciate an annual mulch of gravel. This ensures that excess moisture drains away from the crowns of plants and also shows off the tones of flowers and foliage well. A good mulching is also beneficial to hardy perennial flower garden sedums. In drought gardens, gravel is a good choice.
Unlike most hardy perennials, sedums do not usually die out in the centers as the clumps slowly expand. Instead, the clumps may become so crowded with flowering stems that those at the edges may be forced outwards. In this situation, grow-through plant supports will be especially useful. Because sedums tend not to fade away in the centers of the clumps, they do not usually need lifting and dividing every few years to ensure that they retain their vigor.
Finally, although this may seem counter-intuitive, it’s a good idea to avoid deadheading your sedums. You will find that the plants turn an attractive pale brown in the fall. Cut the plants down in late winter.
Sedums tend not to fade away in the centers of clumps
How to propagate sedum plants
If you are looking to make more free plants, sedums are very easy to propagate. You can take cuttings from plants once they are established and thriving. The stems of many even make roots when stood in a glass of water. Just cut pieces of stem 3-6in (8-15cm) long. Nip the leaves off the lower half of the stem, then place the stem in water up to just below the lowest leaf. Roots will often develop quickly. As soon as they are visible, the rooted cutting can be planted in a pot or in your garden.
Spreading and trailing varieties often make roots where the stems touch the ground. Rooted pieces can simply be snipped off, then potted or planted. In the same way that propagating succulents often works, large-leaved sedums can be propagated by using individual leaves. Cut a stem into pieces with one leaf attached to an inch (2.5cm) of stem. Fill a 3in (8cm) pot with fresh damp potting soil. Push the stem into the soil so that the base of the leaf rests on the soil. Shoots and roots will develop from around where the leaf joins the short piece of stem.
Sedum cuttings will root quickly in water
Sedum problems and how to solve them
Although stonecrops don’t cause too many issues, they are not entirely pest-free. Sedums suffer from many of the same problems as other plants. Slugs and snails like to feast on the emerging spring shoots, while aphids suck the sap of more mature growth.
If you want to get rid of snails, the good news is that modern organic slug and snail treatments (pellets or water-on remedies) are effective. Furthermore, sedums tend to prefer the hot, dry conditions that slugs and snails hate – so you aren’t likely to see extensive damage.
For those looking to get rid of aphids, modern organic treatments are also effective. However, there is no need to apply preventative sprays. Just watch for clusters of aphids on the plants and use your preferred approach. Other problems, such as mildew and rotting at the crown, are usually caused by the soil being too wet. To avoid this issue, water sparingly and only as required.
Keep an eye out for slug and snail damage in spring
Why do my sedum plants fall over?
Hardy perennial flower garden sedums fall over for a number of reasons. If planted in the shade, the stems will become thin and weak and will fail to support themselves. In rich soils, or if overfed, growth will become taller than usual, soft and floppy. So unlike other plants, you should avoid fertilizing your stonecrops. Old, mature plants may become so overcrowded with growth that the stems simply fall outwards. In some, the flower heads are so broad and heavy that the weight of them causes the stems to lean, especially after rain.
Planting in the right conditions is the first step. Sedum can also be cut back by half in late spring, resulting in shorter, bushier plants. Support may be necessary, and grow-through steel frames are ideal. A less expensive approach is to push in canes vertically around the plant and loop twine from cane to cane to create a ‘cage’ to support the stems.
Taller varieties such as ‘Red Cauli’ will benefit from support in the form of canes or frames
Are sedum plants drought resistant?
Yes, most sedum plants will grow naturally in dry climates and dry situations. These include rocky hillsides and screes, and on cliffs. The leaves and stems are adapted to store water. The leaves in particular are noticeably succulent.
Sedums are perfect plants for low rainfall areas, for dry gardens and xeriscaping projects. They are also well suited to green roof planting projects. Not to mention they are ideal plants for garden walls, where the plants will root into cracks.
S. floriferum ‘Weihenstephaner Gold’ has a creeping habit and is good for green roofs, walls and dry slopes
Are sedum plants deer resistant?
No, stonecrops are sadly not deer resistant. They are not the most popular plants with deer, but sedums will be eaten by deer in most gardens. The experts at New Jersey Agricultural Experiment Station have compiled a ratings system that divides plants into four categories from ‘Rarely Damaged’ to ‘Frequently Severely Damaged’. Sedums are rated in the third group as ‘Occasionally Severely Damaged’.
Because they are not exactly the most deer resistant plants, sedums will need protection if you know you have spotted these pests in your yard. Deterrent sprays can work well for some gardeners. However, one guaranteed way to stop deer from eating your stonecrops (and other plants) is to erect a fence.
The SunSparkler Series combines neat growth with great foliage but invest in plant guards and cages to protect from deer
Where to buy sedum
Many sedum varieties are offered in pots at garden centers and other retail outlets. They are available over a long season, as many have such striking foliage that they look just as tempting before flowering time as they do when in bloom. Mail order suppliers will offer pot-grown plants or large plug plants for all manner of modern garden ideas, rockeries, creative borders and drought-resistant plantings. These can be dispatched in spring or fall around planting time.
You can also acquire sedum plants in bare-root form. This means the plants are dug up from the nursery and excess dirt is shaken off the roots before packing. Bare-root plants are often larger than potted plants, and are usually lighter in weight, so they save on shipping costs. Plants for green roofs may also be offered in mats in the same way as grass sods. The mats may comprise a mix of three or four varieties, or a single breed.
Don’t forget you can purchase many sedum varieties online. Use our quick links to find varieties for your plot.
Where to buy sedum in the US:
- Shop sedum plants at Bluestone Perennials
- Shop sedum plants at Digging Dog Nursery
- Shop sedum plants at Garden Crossings
- Shop sedum plants at Monrovia
- Shop sedum plants at Mountain Crest Gardens
- Shop sedum plants at Proven Winners
- Shop sedum plants at White Flower Farm
Where to buy sedum in the UK:
