Repotting guide

When & how to repot Alpine Campion (Silene alpestris)

Also called Alpine campion, Alpine catchfly, Alps campion.

More about alpine campion

About Alpine Campion

Silene alpestris · also called Alpine campion, Alpine catchfly · flowering

Silene alpestris is a low, mat-forming evergreen perennial native to rocky, subalpine meadows and scree slopes in the Eastern Alps and Apennines. From late spring into early summer it produces showers of small, deeply fringed, star-shaped white flowers on slender branching stems above compact dark-green foliage. It thrives in moderately fertile, gritty, neutral to alkaline, well-drained soil in full sun or light part-shade, and strongly resents winter wet. The ASPCA lists the related Silene acaulis (moss campion) as non-toxic to dogs, cats, and horses; Silene alpestris is classified as mildly-toxic in the absence of a species-specific ASPCA listing.

Mature size: 15–25 cm tall in flower, spreading to 30–40 cm wide.

How to tell alpine campion needs repotting

Repotting on a calendar is less reliable than reading the plant. For alpine campion, 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 alpine campion

Every 2–3 years, into bone-dry mix. Alpine Campion's growth habit — low, loosely mat-forming, evergreen perennial spreading by rooting stems. — sets the pace. Silene alpestris is a low, mat-forming evergreen perennial native to rocky, subalpine meadows and scree slopes in the Eastern Alps and Apennines. From late spring into early summer it produces showers of small, deeply fringed, star-shaped white flowers on slender branching stems above compact dark-green foliage. It thrives in moderately fertile, gritty, neutral to alkaline, well-drained soil in full sun or light part-shade, and strongly resents winter wet. The ASPCA lists the related Silene acaulis (moss campion) as non-toxic to dogs, cats, and horses; Silene alpestris is classified as mildly-toxic in the absence of a species-specific ASPCA listing.

What size pot to step alpine campion up to

Use a pot only one size up — or even the same pot with fresh gritty mix if the roots have room. Alpine Campion 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 alpine campion

Spring or summer, while alpine campion 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 alpine campion

Repot dry. Do not water alpine campion 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 gritty, moderately fertile, well-drained; neutral to alkaline; chalk, loam, or sand 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 alpine campion 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 alpine campion 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 alpine campion

Alpine Campion wants gritty, moderately fertile, well-drained; neutral to alkaline; chalk, loam, or sand. Avoid heavy, clay-rich or moisture-retentive soils; a mix of loam and horticultural grit (1:1) suits it well in beds or containers. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting alpine campion — frequently asked questions

How often should you repot alpine campion?

Every 2–3 years, into bone-dry mix for alpine campion. Repot alpine campion every 2–3 years into a snug pot of gritty, moderately fertile, well-drained; neutral to alkaline; chalk, loam, or sand, 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 alpine campion need?

When is the best time of year to repot alpine campion?

Should you water alpine campion after repotting?

No — not straight away. Repot alpine campion 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 alpine campion after repotting?

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