Purple Emperor sedum

Sun

Full sun gives the darkest foliage and strongest stems; light shade is tolerated but can produce greener leaves and floppy growth.

Water

Water regularly during establishment, allowing the soil to dry between waterings. Established plants need extra water mainly during prolonged drought; avoid persistently damp soil.

Soil

Well-drained sandy, gravelly or loamy soil, preferably of low to moderate fertility. Heavy clay needs improved drainage, especially where winters are wet.

Height

1-1.5 ft (0.3-0.45 m)

Spread

1.5-2 ft (0.45-0.6 m)

Flowers

Late summer to early autumn; broad, flat clusters of dusky pink flowers that age to rusty brown.

Foliage

Fleshy, oval, lightly toothed leaves in deep burgundy-purple on dark stems; colour is strongest in full sun.

Growth

Moderate

Care needed

Low

• Pollinators
• Drought tolerant
• Cold hardy
• Heat tolerant
• Wildlife
• Low allergen

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Easy

Toughness

Very tough

Pick your zone, country, light and whether you have pets.

1. Planting day

   1 ft (0.3 m)

2. After 1 year

   1.1 ft (0.32 m)

3. After 2 years

   1.1 ft (0.35 m)

4. After 3 years

   1.2 ft (0.38 m)

   full size

About 3 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Safe

Growth rate

Moderate

• Plant with the crown at soil level in a sunny position with free drainage.
• Water new plants through their first growing season, letting the soil dry between soakings.
• Avoid routine feeding; rich soil and high-nitrogen fertiliser encourage weak, sprawling stems.
• Use a light gravel mulch if needed, keeping the crown clear of wet organic mulch.
• Divide in spring when the centre becomes bare or the clump loses vigour.

Pruning. Leave sound stems and seed heads standing through winter, then cut them to ground level in late winter or early spring before new shoots lengthen. Remove collapsed or rotting stems sooner.

Late winter

Cut back old stems before new growth develops, taking care not to damage emerging buds.

Spring

Plant or divide clumps once the soil is workable; water them in thoroughly.

Late spring

Check young shoots for slug and snail damage and remove pests where necessary.

Summer

Water establishing plants during dry spells; check that established clumps are not becoming waterlogged or shaded.

Late summer

Leave flowers available to pollinators rather than cutting all stems for arrangements.

Autumn

Keep firm, upright seed heads for winter interest and clear fallen leaves away from the crown.

• Repeat small groups along the front or middle of a sunny border to create a rhythm of dark foliage.
• Pair with fine-textured ornamental grasses for contrast with its fleshy leaves and flat flower heads.
• Combine with silver-leaved plants in a gravel garden for a restrained purple-and-silver planting.
• Use in a sunny container with drainage holes and a free-draining potting mix.
• Include in a late-season pollinator border with asters and coneflowers.

Garden styles it suits: New perennial (prairie), Dry gravel garden, Pollinator garden, Low-maintenance, Autumn colour and Modern.

Plant it with: Lamb's ears, Catmint, Russian sage, Purple coneflower, Feather reed grass and New England aster.

Wildlife: The open flower clusters provide late-season nectar and pollen for bees, hoverflies and butterflies. Standing stems offer some shelter for overwintering invertebrates.

• Crown or root rot in wet soil: improve drainage or move the plant to a raised position; discard badly rotted crowns.
• Flopping stems: provide more sun, stop feeding and avoid excessive watering; divide overcrowded clumps in spring.
• Slugs and snails eating emerging shoots: inspect new growth and hand-pick pests or use an approved iron-phosphate bait as directed.
• Vine weevil larvae damaging roots, especially in pots: inspect declining plants and use a locally approved biological control when conditions suit it.

Not known to be toxic to cats, dogs, horses or people. No part is recognised as seriously poisonous, although eating plant material may cause mild stomach upset; cultivar-specific toxicity information is limited.

• Matrona sedum (Hylotelephium 'Matrona')

  Usually taller, with grey-green leaves flushed purple and strong purple stems, rather than the consistently dark burgundy foliage of Purple Emperor.

• Autumn Joy sedum (Hylotelephium 'Herbstfreude')

  Has green leaves and generally taller, broader clumps; its flower heads become coppery red rather than providing dark purple foliage throughout the growing season.

The name Purple Emperor reflects the cultivar's deep purple foliage.

Propagation. Divide clumps in spring or take non-flowering stem cuttings in late spring to early summer. These methods preserve the cultivar; seedlings will not reliably retain its dark foliage or other characteristics.

Accepted botanical name

Hylotelephium

Sources: GBIF (CC BY 4.0). The care and design notes are LandscapeGPT's own.