Repotting guide

When & how to repot Hylotelephium 'Purple Emperor' (Hylotelephium 'Purple Emperor')

Also called Purple Emperor sedum, purple stonecrop.

More about hylotelephium 'purple emperor'

About Hylotelephium 'Purple Emperor'

Hylotelephium 'Purple Emperor' · also called Purple Emperor sedum, purple stonecrop · flowering

'Purple Emperor' is a dark-leaved stonecrop grown as much for its smoky purple-black foliage as for the dusky pink flower heads it carries in late summer. The deep leaf colour intensifies in full sun, contrasting beautifully with the rose blooms and the bees they draw. It is compact, drought-tolerant and undemanding in lean, well-drained soil.

Mature size: 40-50 cm tall and 40-50 cm wide (16-20 in).

Watch for — Foliage greening / loss of colour: Insufficient sun reverts the purple leaves toward green. Move to a fully sunny, open spot to restore the dark tones.

How to tell hylotelephium 'purple emperor' needs repotting

Repotting on a calendar is less reliable than reading the plant. For hylotelephium 'purple emperor', watch for these signs:

Roots growing out of the drainage holes, or the rootball lifting the plant proud of the rim.
Soil that has shrunk away from the pot sides and no longer holds water.
The pot is unstable because the plant has grown top-heavy.
Old, compacted, broken-down mix that stays wet too long — for a succulent that is a rot risk, so refresh it even if the pot size is fine.

For the underlying biology of a pot-bound root system and why it stalls a plant, see our guide to spotting and fixing a root-bound plant.

How often to repot hylotelephium 'purple emperor'

Every 2–3 years, into bone-dry mix. Hylotelephium 'Purple Emperor''s growth habit — upright clump-forming herbaceous perennial with dark succulent stems and leaves; flat flower heads cap the stems. dies back in winter and reshoots dark-purple in spring. — sets the pace. 'Purple Emperor' is a dark-leaved stonecrop grown as much for its smoky purple-black foliage as for the dusky pink flower heads it carries in late summer. The deep leaf colour intensifies in full sun, contrasting beautifully with the rose blooms and the bees they draw. It is compact, drought-tolerant and undemanding in lean, well-drained soil.

What size pot to step hylotelephium 'purple emperor' up to

Use a pot only one size up — or even the same pot with fresh gritty mix if the roots have room. Hylotelephium 'Purple Emperor' stores water and rots in a large pot of slow-drying soil. A tight terracotta pot that dries fast is far safer than a generous plastic one. Never up-pot a succulent by several sizes.

Not sure of the exact diameter? Our pot size calculator takes the current pot and root spread and tells you the right next size — it deliberately recommends a single step up, never a big jump.

The best time of year to repot hylotelephium 'purple emperor'

Spring or summer, while hylotelephium 'purple emperor' is in active growth and warm, is best — roots recover fastest then, and the plant is not sitting in cool damp soil. Avoid repotting a succulent in winter dormancy.

Step-by-step: repotting hylotelephium 'purple emperor'

Repot dry. Do not water hylotelephium 'purple emperor' for several days first. Working with dry roots and dry mix dramatically lowers the rot risk for a succulent.
Pick a snug, fast-draining pot. Choose terracotta one size up at most, with a drainage hole. Have gritty lean, gritty, free-draining loam or sandy soil ready.
Tip it out and clean the roots. Slide the plant out, crumble off the old soil, and trim any black, mushy or dead roots with clean snips.
Pot into dry mix. Set hylotelephium 'purple emperor' at its original depth in dry gritty mix, firming gently. Do not bury the stem deeper than it was.
Wait a week before watering. Leave it completely dry and out of harsh sun for about 7 days so any damaged roots callus. Only then water lightly.

Aftercare

Keep hylotelephium 'purple emperor' completely dry and out of fierce sun for about a week so any nicked roots callus before they meet moisture; watering a freshly repotted succulent is the classic way to rot it. Then resume the normal lean, dry rhythm. Do not fertilise for about 3 weeks — fresh mix already carries nutrients and feeding freshly disturbed roots scorches them.

The right soil mix for hylotelephium 'purple emperor'

Hylotelephium 'Purple Emperor' wants lean, gritty, free-draining loam or sandy soil. Thrives on poor soils with neutral to slightly alkaline pH. Avoid fertile, damp ground, which dilutes the leaf colour and weakens stems. Add grit on clay. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting hylotelephium 'purple emperor' — frequently asked questions

How often should you repot hylotelephium 'purple emperor'?

Every 2–3 years, into bone-dry mix for hylotelephium 'purple emperor'. Repot hylotelephium 'purple emperor' every 2–3 years into a snug pot of lean, gritty, free-draining loam or sandy soil, ideally in spring or summer. Let it sit in dry soil and do not water for about a week afterwards so any nicked roots can callus. Over-potting and watering straight away is what rots succulents.

What size pot does hylotelephium 'purple emperor' need?

When is the best time of year to repot hylotelephium 'purple emperor'?

Should you water hylotelephium 'purple emperor' after repotting?

No — not straight away. Repot hylotelephium 'purple emperor' into dry mix and wait about a week before the first watering so any damaged roots callus over. Watering a freshly repotted succulent is the single most common way to rot one.

Should you fertilise hylotelephium 'purple emperor' after repotting?

Not immediately. Wait about 3 weeks after repotting hylotelephium 'purple emperor'. Fresh mix already contains nutrients, and feeding freshly cut or disturbed roots burns them. Resume your normal feeding routine once you see new growth.