Repotting guide

When & how to repot Rock Candytuft (Iberis saxatilis)

Also called Rock Candytuft, Saxatile Candytuft.

More about rock candytuft

About Rock Candytuft

Iberis saxatilis · also called Rock Candytuft, Saxatile Candytuft · flowering

A diminutive, mat-forming evergreen subshrub native to rocky limestone outcrops in southern Europe. Produces small white flower heads in spring and maintains neat, dark-green foliage year-round. Exceptionally tolerant of poor, stony, alkaline soils — a superb choice for troughs, alpine gardens, and dry-stone walls.

Mature size: 5–15 cm tall, 20–40 cm wide

Watch for — Crown and root rot: The primary killer of this species — caused by waterlogged soil or winter wet. Plant in raised beds, troughs, or dry-stone wall crevices to ensure free drainage. Never allow water to pool around the crown.

How to tell rock candytuft needs repotting

Repotting on a calendar is less reliable than reading the plant. For rock candytuft, 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 rock candytuft

Every 2–3 years, into bone-dry mix. Rock Candytuft's growth habit — compact, cushion- to mat-forming evergreen subshrub — sets the pace. A diminutive, mat-forming evergreen subshrub native to rocky limestone outcrops in southern Europe. Produces small white flower heads in spring and maintains neat, dark-green foliage year-round. Exceptionally tolerant of poor, stony, alkaline soils — a superb choice for troughs, alpine gardens, and dry-stone walls.

What size pot to step rock candytuft up to

Use a pot only one size up — or even the same pot with fresh gritty mix if the roots have room. Rock Candytuft 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 rock candytuft

Spring or summer, while rock candytuft 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 rock candytuft

Repot dry. Do not water rock candytuft 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 very sharply drained, gritty or rocky, alkaline to 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 rock candytuft 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 rock candytuft 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 rock candytuft

Rock Candytuft wants very sharply drained, gritty or rocky, alkaline to neutral soil. Thrives in lean, stony, limestone-based soils. Incorporate up to 50% coarse grit or pea gravel into compost for container culture. pH 6.5–8.0. Fertility is less important than drainage. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting rock candytuft — frequently asked questions

How often should you repot rock candytuft?

Every 2–3 years, into bone-dry mix for rock candytuft. Repot rock candytuft every 2–3 years into a snug pot of very sharply drained, gritty or rocky, alkaline to 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 rock candytuft need?

When is the best time of year to repot rock candytuft?

Should you water rock candytuft after repotting?

No — not straight away. Repot rock candytuft 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 rock candytuft after repotting?

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