Repotting guide

When & how to repot Geranium sylvaticum (Geranium sylvaticum)

Also called Wood cranesbill, Woodland geranium.

More about geranium sylvaticum

About Geranium sylvaticum

Geranium sylvaticum · also called Wood cranesbill, Woodland geranium · flowering

Wood cranesbill is a clump-forming hardy perennial from European woodland margins and damp meadows, bearing saucer-shaped violet-blue to mauve flowers with pale centres in early summer above deeply lobed leaves. It thrives in dappled shade and moist soil, flowers around May to July, dies back over winter and returns reliably each spring.

Mature size: Typically 50-75 cm tall and 50-60 cm wide at maturity

Watch for — Vine weevil (in containers): Notched leaf edges and sudden collapse from larvae eating roots. Inspect rootballs, use biological nematode controls, or grow in open ground where damage is rare.

How to tell geranium sylvaticum needs repotting

Repotting on a calendar is less reliable than reading the plant. For geranium sylvaticum, 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 geranium sylvaticum) 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 geranium sylvaticum

Only every 2–4 years, when genuinely crowded. Geranium sylvaticum 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. Clump-forming, upright herbaceous perennial that forms a mound of deeply palmate, lobed foliage topped by branching flower stems. Spreads slowly by rhizomes to make weed-suppressing colonies; dies back to the ground in winter..

What size pot to step geranium sylvaticum up to

Go up only one pot size — roughly 2–3 cm (about an inch) wider in diameter, no more. Geranium sylvaticum 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 geranium sylvaticum 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 geranium sylvaticum

Early spring, just as new growth restarts, is the ideal window for geranium sylvaticum. 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 geranium sylvaticum

Confirm it actually needs it. Slide geranium sylvaticum 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 geranium sylvaticum 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 fertile, humus-rich, moisture-retentive loam, 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 geranium sylvaticum 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 geranium sylvaticum

Geranium sylvaticum wants fertile, humus-rich, moisture-retentive loam. Grows in any reasonable garden soil that holds moisture, ideally enriched with leaf mould or compost. Tolerates neutral to slightly alkaline or acid soils; avoid baking-dry, free-draining sites. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting geranium sylvaticum — frequently asked questions

How often should you repot geranium sylvaticum?

Only every 2–4 years, when genuinely crowded for geranium sylvaticum. Only repot geranium sylvaticum 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 fertile, humus-rich, moisture-retentive loam. The key mistake is over-potting: a too-big pot stays wet and rots the roots.

What size pot does geranium sylvaticum need?

When is the best time of year to repot geranium sylvaticum?

Does geranium sylvaticum like to be root-bound?

Yes — geranium sylvaticum 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 geranium sylvaticum after repotting?

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