Perennial succulent
How to grow sedum
Hylotelephium spectabile (syn. Sedum spectabile)
Border sedums, now classed as Hylotelephium, are fully hardy succulent perennials that flower from August to October. Plant them from March to May in full sun and lean, free-draining soil, 45 to 60 cm apart. The thing that goes wrong is flopping: in rich soil, shade or after feeding, the stems splay open from the centre just as the flowers colour. Poor soil, no fertiliser and cutting the stems back by a third in late May keep the plant upright.
- Hardiness
- Fully hardy
- Position
- Full sun
- Soil
- Free-draining, lean, gritty
- Ideal pH
- 6.0 to 7.5
- Water
- Low
- Feeding
- Light feeder
Sowing and planting sedum
WhenPlant Mar to May; flowers Aug to Oct; cut down Feb
Starting off
Plant pot-grown plants Mar to May. Divide clumps in Mar every 3 to 4 years, the easiest method; stem cuttings 8 cm long in May to Jun root in 2 to 3 weeks in gritty compost, and even a single leaf will root. Seed is variable and rarely sown.
Spacing and planting
Plant 45 to 60 cm apart as a clump spreads 60 cm; plant at pot depth with grit on clay. Fine in a 30 cm pot of gritty compost; smaller Sedum spurium types suit a 15 cm pan.
Varieties worth growing
- 'Herbstfreude' (Autumn Joy)
- The classic: flat heads that open pink in August and deepen to brick red by October, on 60 cm stems.
- 'Matrona'
- Grey-purple leaves on dark red stems with pale pink flowers; more upright than most, so less likely to splay.
- 'Purple Emperor'
- Dark purple foliage from spring and dusky red flowers on a compact 40 cm plant; needs full sun to keep its colour.
- H. spectabile 'Brilliant'
- Bright pink heads over pale green leaves; the one that draws the most butterflies in September.
- Sedum spurium 'Schorbuser Blut' (Dragon's Blood)
- A 10 cm mat-former with red-tinted leaves and deep red flowers in summer, for pans, gravel and wall tops.
Sedum month by month
Timings are for central England. Allow two weeks later in the north and on cold, heavy soil.
- January
Nothing to do. Leave the dried heads standing.
- February
Cut the old stems to the ground, taking care not to snap the new rosettes at the base.
- March
Plant. Lift and divide clumps that have gone bare in the middle.
- April
Plant. Watch for slugs on the new growth.
- May
In the last week cut every stem back by a third. Push the trimmings into gritty compost as cuttings.
- June
Take stem cuttings if you want more plants. Nothing else.
- July
Nothing to do. Do not water established plants in the ground.
- August
Flower heads colour up. Check pots for vine weevil and apply nematodes late in the month.
- September
Peak flowering, covered in bees and butterflies.
- October
Heads darken to russet. Leave them on.
- November
Nothing to do. Raise pots on feet for the winter.
- December
Nothing to do.
Feeding sedum
Do not feed sedum in the ground. It stores what it needs in its leaves, and any extra nitrogen makes the stems soft so the clump falls open. A pinch of seaweed meal in pot compost is the most it ever wants.
Very low, rich soil makes it flop. A drought-tolerant succulent.
Feeding plan
Beds, all year
Nothing
No fertiliser, no manure and no rich mulch. If the soil is heavy, add grit, not compost.
Potting or repotting, in March or April
5 ml per litre of compost, the low end of the label: 60 ml, four level tablespoons, mixed into a 30 cm pot holding 12 litres. No further feed that year.
May, only for a pot left in the same compost for more than two years
1 g per litre of water, the label rate, as a single drench: 2 g in a 2 litre can.
No fertiliser is recommended for sedum in open ground. The two seaweed products are for pots only.
Signs to watch
Stems splay open from the centre in Aug
Rich soil, feed or shade
Chelsea chop in May, no feed, full sun
Leaves yellow and mushy at the base
Waterlogging
Lift and replant on grit
Pale, small heads on an old clump
Congestion
Divide in Mar
Pests, diseases and problems
Plants in pots wilt and lift out of the compost with almost no roots; leaf edges notched
Vine weevil: the white grubs eat the roots, the adult beetles notch the leaves at night
Water nematodes into pots in late August or September and again in April or May when the compost is warm enough; pick adults off by torchlight; repot into fresh compost and check the root ball for grubs.
New rosettes at ground level eaten or scraped in March and April
Slugs and snails sheltering in the old stems
Clear the old stems in February, keep the crown free of debris, and patrol on damp evenings until the shoots are 10 cm tall.
Black or green insects packed among the flower buds, heads sticky
Aphids
Wash them off with a firm jet of water before the flowers open; avoid any spray once the heads are in bloom and covered in bees.
Stems blacken at soil level and pull away in a wet autumn or winter
Fungal stem and crown rot in heavy, wet ground
Cut out affected stems to clean tissue, lift the clump in March, and replant healthy pieces in a raised spot with grit worked in.
Pruning
Pruning and care
Give a 'Chelsea chop' in late May, cutting stems back by a third, so plants stay compact and do not splay open in Aug. Leave the dried flower heads over winter for structure and cut them to the ground in Feb. No staking if chopped; divide in Mar every 3 to 4 years as the centre dies out. Fully hardy, no protection.
Good to knowLeave seed heads for winter structure; the autumn flowers are bee magnets.
Growing sedum in pots
Sedum is one of the easiest perennials for a pot because it forgives missed watering. Use a 30 cm pot, about 12 litres, with equal parts loam-based compost and grit, and a pot with large drainage holes. Water only when the compost has dried out, perhaps once a week in summer, and not at all in winter. Mat-forming Sedum spurium is happy for years in a shallow 15 cm pan. The one real risk in pots is vine weevil, so tip the plant out each spring, check the roots, and treat with nematodes if you find grubs.
Sedum: common questions
Why does my sedum flop over?
Sedum flops when the soil is too rich, the site too shady, or the clump old and congested. The stems grow tall and soft and splay out from the centre under the weight of the flowers. Stop feeding, move it into full sun, cut the stems back by a third in late May, and divide the clump in March every three to four years.
When should I cut back sedum?
Cut the old stems to the ground in February. The dried flower heads are worth leaving all winter for their shape and for the shelter they give, and by February you can see the new rosettes at the base. A second cut, the Chelsea chop, takes a third off the new stems in late May to keep them short and sturdy.
Is sedum good for bees and butterflies?
Yes, the flat heads of Hylotelephium spectabile and 'Herbstfreude' are among the best late nectar sources in the garden. They open in August and September when little else is in flower, and draw honeybees, bumblebees, hoverflies and butterflies such as small tortoiseshells and red admirals. Plant them in full sun, where insects feed most.
Sources
Growing information on this page was checked against these references in November 2026. Feeding rates are Dr Forest label rates.