Repotting guide

When & how to repot Diana Clare Pulmonaria (Pulmonaria 'Diana Clare')

Also called Diana Clare lungwort, silver lungwort.

More about diana clare pulmonaria

About Diana Clare Pulmonaria

Pulmonaria 'Diana Clare' · also called Diana Clare lungwort, silver lungwort · flowering

'Diana Clare' is an award-winning lungwort with long, almost wholly silver leaves and early spring flowers that open violet-pink and deepen to rich blue-violet. It forms vigorous, weed-suppressing clumps for moist shade. Pulmonaria isn't individually ASPCA-listed, so treat it with caution around pets.

Mature size: 25-35 cm (10-14 in) tall, spreading 45-60 cm (18-24 in) wide.

Watch for — Scorched or dulled silver leaves: Too much sun or dry roots burns and fades the foliage. Relocate to deeper shade and keep the root zone moist and mulched.

How to tell diana clare pulmonaria needs repotting

Repotting on a calendar is less reliable than reading the plant. For diana clare pulmonaria, 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 diana clare pulmonaria) 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 diana clare pulmonaria

Only every 2–4 years, when genuinely crowded. Diana Clare Pulmonaria 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. Low, vigorous, clump-forming semi-evergreen perennial spreading by rhizomes into dense, silver ground cover. Flower stems rise early in spring above long, bristly, near-white leaves..

What size pot to step diana clare pulmonaria up to

Go up only one pot size — roughly 2–3 cm (about an inch) wider in diameter, no more. Diana Clare Pulmonaria 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 diana clare pulmonaria 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 diana clare pulmonaria

Early spring, just as new growth restarts, is the ideal window for diana clare pulmonaria. 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 diana clare pulmonaria

Confirm it actually needs it. Slide diana clare pulmonaria 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 diana clare pulmonaria 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 moist, humus-rich, well-drained 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 diana clare pulmonaria 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 diana clare pulmonaria

Diana Clare Pulmonaria wants moist, humus-rich, well-drained loam. Prefers fertile woodland soil rich in organic matter, moist but never waterlogged. Neutral to slightly alkaline pH is ideal. Improve with compost or leaf mould; avoid hot, dry positions. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting diana clare pulmonaria — frequently asked questions

How often should you repot diana clare pulmonaria?

Only every 2–4 years, when genuinely crowded for diana clare pulmonaria. Only repot diana clare pulmonaria 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 moist, humus-rich, well-drained loam. The key mistake is over-potting: a too-big pot stays wet and rots the roots.

What size pot does diana clare pulmonaria need?

When is the best time of year to repot diana clare pulmonaria?

Does diana clare pulmonaria like to be root-bound?

Yes — diana clare pulmonaria 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 diana clare pulmonaria after repotting?

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