Repotting guide

When & how to repot Vandell's Rock Jasmine (Androsace vandellii)

Also called Vandell's Rock Jasmine, Silver Rock Jasmine, Silky Androsace.

More about vandell's rock jasmine

About Vandell's Rock Jasmine

Androsace vandellii · also called Vandell's Rock Jasmine, Silver Rock Jasmine · flowering

Androsace vandellii (syn. Androsace tomentosa) is a specialist high-alpine cushion plant native to siliceous rock faces and crevices in the Alps, Apennines, Pyrenees, and Sierra Nevada above 2,000 m. It forms beautifully symmetrical, silver-grey cushions of tiny rosettes densely covered in star-shaped white hairs, bearing stemless white flowers with a yellow eye in April. It is one of the most exacting Androsace species in cultivation, demanding perfect drainage, sharp aeration, vertical planting in acidic gritty soil, and protection from winter wet — typically grown in an alpine house. Androsace is not listed on the ASPCA database; classified as mildly-toxic out of caution.

Mature size: 2–5 cm tall and up to 15 cm across.

Watch for — Aphids under glass: Cushion species grown in alpine houses are susceptible to root and shoot aphids; inspect regularly and treat with a systemic insecticide appropriate for ornamental use, avoiding wetting the cushion.

How to tell vandell's rock jasmine needs repotting

Repotting on a calendar is less reliable than reading the plant. For vandell's rock jasmine, 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 vandell's rock jasmine

Every 2–3 years, into bone-dry mix. Vandell's Rock Jasmine's growth habit — tightly domed, silvery cushion-forming evergreen perennial; extremely slow-growing and long-lived when conditions are right. — sets the pace. Androsace vandellii (syn. Androsace tomentosa) is a specialist high-alpine cushion plant native to siliceous rock faces and crevices in the Alps, Apennines, Pyrenees, and Sierra Nevada above 2,000 m. It forms beautifully symmetrical, silver-grey cushions of tiny rosettes densely covered in star-shaped white hairs, bearing stemless white flowers with a yellow eye in April. It is one of the most exacting Androsace species in cultivation, demanding perfect drainage, sharp aeration, vertical planting in acidic gritty soil, and protection from winter wet — typically grown in an alpine house. Androsace is not listed on the ASPCA database; classified as mildly-toxic out of caution.

What size pot to step vandell's rock jasmine up to

Use a pot only one size up — or even the same pot with fresh gritty mix if the roots have room. Vandell's Rock Jasmine 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 vandell's rock jasmine

Spring or summer, while vandell's rock jasmine 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 vandell's rock jasmine

Repot dry. Do not water vandell's rock jasmine 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, very sharply drained acidic gritty mix 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 vandell's rock jasmine 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 vandell's rock jasmine 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 vandell's rock jasmine

Vandell's Rock Jasmine wants lean, very sharply drained acidic gritty mix. Naturally grows on non-calcareous (silicate/igneous) rock; use a mix of 1 part peat-free ericaceous compost to 3 parts coarse grit or granite chips, with pH 3.5–6.5; lime-rich soils cause rapid decline. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting vandell's rock jasmine — frequently asked questions

How often should you repot vandell's rock jasmine?

Every 2–3 years, into bone-dry mix for vandell's rock jasmine. Repot vandell's rock jasmine every 2–3 years into a snug pot of lean, very sharply drained acidic gritty mix, 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 vandell's rock jasmine need?

When is the best time of year to repot vandell's rock jasmine?

Should you water vandell's rock jasmine after repotting?

No — not straight away. Repot vandell's rock jasmine 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 vandell's rock jasmine after repotting?

Not immediately. Wait about 3 weeks after repotting vandell's 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.