Repotting guide

When & how to repot Cylindrical Rock Jasmine (Androsace cylindrica)

Also called Cylindrical Rock Jasmine, Cylindrical Androsace.

More about cylindrical rock jasmine

About Cylindrical Rock Jasmine

Androsace cylindrica · also called Cylindrical Rock Jasmine, Cylindrical Androsace · flowering

Cylindrical Rock Jasmine is a rare, specialist alpine perennial endemic to the Pyrenees, forming extraordinarily tight, elongated cylindrical rosettes that build into dense domed cushions. White flowers with a yellow eye appear in spring. One of the most challenging Androsace species in cultivation, it is grown almost exclusively by specialist alpine enthusiasts in an alpine house or tufa garden.

Mature size: 2–5 cm tall, spreading 5–10 cm wide over many years

Watch for — Extremely slow establishment: Even under ideal alpine house conditions, this species grows only a few millimetres per year. Impatient management — repotting too frequently or disturbing the root run — sets growth back by seasons. Handle only when strictly necessary and treat as a long-term specimen.

How to tell cylindrical rock jasmine needs repotting

Repotting on a calendar is less reliable than reading the plant. For cylindrical rock jasmine, watch for these signs:

Roots spiralling thickly out of the drainage holes or pushing the whole plant up out of the pot.
The pot is so packed that water runs straight through in seconds and barely wets the soil.
It has split a plastic pot, or the rootball is a solid mass with almost no soil left when you slide it out.
Growth and (for cylindrical rock jasmine) flowering have clearly stalled despite good light and feeding — but remember this plant likes being snug, so a little crowding alone is not a reason to repot.

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 cylindrical rock jasmine

Only every 2–4 years, when genuinely crowded. Cylindrical Rock Jasmine is one of the plants that genuinely prefers a snug pot — it grows and flowers better with its roots a little restricted, so resist the urge to repot it on schedule. Extremely tight, domed cushion of elongated cylindrical rosettes; very slow-growing.

What size pot to step cylindrical rock jasmine up to

Go up only one pot size — roughly 2–3 cm (about an inch) wider in diameter, no more. Cylindrical Rock Jasmine positively prefers a snug pot: it flowers and grows better when the roots are a little restricted. The single biggest repotting mistake here is over-potting — dropping cylindrical rock jasmine into a pot two or three sizes up. All that surplus soil holds water the small root system cannot use, stays cold and wet, and rots the roots within weeks. When in doubt, choose the smaller pot.

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 cylindrical rock jasmine

Early spring, just as new growth restarts, is the ideal window for cylindrical rock jasmine. The plant is moving into its strongest growth phase and re-roots into fresh soil quickly. Avoid repotting in winter dormancy or, for flowering plants, while it is in bud or bloom — recovery is slowest then and you risk dropping the flowers.

Step-by-step: repotting cylindrical rock jasmine

Confirm it actually needs it. Slide cylindrical rock jasmine out and check the roots. Only continue if it is genuinely packed — this plant prefers a snug pot, so if there is still soil and room, put it straight back.
Pick a pot only one size up. Choose a pot just 2–3 cm wider with good drainage. Resist anything bigger; over-potting is the main killer here.
Ease it out gently. Water lightly the day before, then tip cylindrical rock jasmine out, supporting the base. Tease the outer roots free only enough to stop them circling.
Repot at the same depth. Add a layer of fresh vertical tufa crevice or pure limestone grit, set the plant so the soil line sits exactly where it did before, and backfill around the sides, firming lightly.
Settle it in. Water once to settle the soil, then let it sit. Hold off on more water until the top of the soil dries — fresh soil around a small root system stays wet for a while.

Aftercare

Because the new soil holds more water than the old crammed rootball did, ease right back on watering — let the top of the soil dry before you water cylindrical rock jasmine again, or you will rot the roots in the very pot you just moved it to. Keep it out of harsh direct sun for a fortnight. Do not fertilise for about 4 weeks — fresh mix already carries nutrients and feeding freshly disturbed roots scorches them.

The right soil mix for cylindrical rock jasmine

Cylindrical Rock Jasmine wants vertical tufa crevice or pure limestone grit. Best grown wedged into crevices of natural tufa rock, which provides a stable, moisture-buffering, alkaline, and porous root environment. In pots, use 80–90% fine limestone grit with minimal loam; alkaline pH (7.0–8.0) is essential as the species is strictly calcicole. No organic material in the mix. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting cylindrical rock jasmine — frequently asked questions

How often should you repot cylindrical rock jasmine?

Only every 2–4 years, when genuinely crowded for cylindrical rock jasmine. Only repot cylindrical rock jasmine every 2–4 years, and only when it is genuinely root-bound — it flowers and grows best slightly crowded. Step up just one pot size in spring using vertical tufa crevice or pure limestone grit. The key mistake is over-potting: a too-big pot stays wet and rots the roots.

What size pot does cylindrical rock jasmine need?

When is the best time of year to repot cylindrical rock jasmine?

Does cylindrical rock jasmine like to be root-bound?

Yes — cylindrical rock jasmine genuinely flowers and grows best when slightly pot-bound, so do not rush to repot it. The mistake to avoid is over-potting into a much larger pot: the excess soil stays wet, the roots cannot use it, and the plant rots. Only repot every few years and only one snug size up.

Should you fertilise cylindrical rock jasmine after repotting?

Not immediately. Wait about 4 weeks after repotting cylindrical rock jasmine. Fresh mix already contains nutrients, and feeding freshly cut or disturbed roots burns them. Resume your normal feeding routine once you see new growth.