Repotting guide

When & how to repot Alpine Balsam (Erinus alpinus)

Also called Alpine Balsam, Fairy Foxglove, Alpine Liver Balsam.

More about alpine balsam

About Alpine Balsam

Erinus alpinus · also called Alpine Balsam, Fairy Foxglove · flowering

Alpine Balsam is a charming, short-lived perennial or biennial native to mountain crevices in the Pyrenees and Alps. It produces a profusion of small, bright pink to purple five-petalled flowers from late spring to early summer. Perfect for planting in wall crevices, rock gardens, and paving gaps, it self-seeds freely in suitable spots.

Mature size: 8–15 cm tall, 15–25 cm spread

How to tell alpine balsam needs repotting

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

Every 2–3 years, into bone-dry mix. Alpine Balsam's growth habit — low, rosette-forming, short-lived perennial or biennial — sets the pace. Alpine Balsam is a charming, short-lived perennial or biennial native to mountain crevices in the Pyrenees and Alps. It produces a profusion of small, bright pink to purple five-petalled flowers from late spring to early summer. Perfect for planting in wall crevices, rock gardens, and paving gaps, it self-seeds freely in suitable spots.

What size pot to step alpine balsam up to

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

Spring or summer, while alpine balsam 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 balsam

Repot dry. Do not water alpine balsam 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, well-drained alkaline or neutral 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 alpine balsam 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 balsam 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 balsam

Alpine Balsam wants gritty, well-drained alkaline or neutral soil. Naturally grows in limestone crevices. Prefers a lean, gritty mix with pH 6.5–8.0. Add crushed limestone or pea gravel to a loam base. Rich, acidic soils produce large floppy leaves and few flowers. 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 balsam — frequently asked questions

How often should you repot alpine balsam?

Every 2–3 years, into bone-dry mix for alpine balsam. Repot alpine balsam every 2–3 years into a snug pot of gritty, well-drained alkaline or neutral 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 alpine balsam need?

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

Should you water alpine balsam after repotting?

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

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