Plant Lungwort – Cool Window

Pulmonaria settles best in cool plant and divide windows — early spring or early autumn — with moist soil around the crown. Leaf silvering and flower colour do not change plant-out week.

Shared site, mildew, and summer water live on How to Grow Pulmonaria; foliage and flower bands on Types of Pulmonaria.

Cool windows that clear Pulmonaria for plant-out and divide

Cool weather is the stake. A beautiful pot still fails if you drop it into baking dry soil the weekend a heat wave arrives. Autumn plant- out needs enough mild weeks for roots to bite before freeze. Spring plant-out needs moisture as leaves and early flowers expand.

Blue Ensign follows the same cool window as every other Pulmonaria here. Confirm the table above, then open depth and spacing.

Moist soil planting steps for spotted silver

1. Dig a pocket in moist shade; loosen the base.
2. Blend compost so moisture holds without a water bowl under the crown.
3. Set the crown at the same depth as the nursery pot.
4. Firm gently and water once to settle the soil.
5. Mulch lightly; keep mulch off the collar.
6. Label the patch — early spring gaps look empty until leaves rise.
7. Hold strong fertiliser until growth is active.

Too deep in cold wet clay delays and rots. Too shallow in baking sand dries the crown. Match pot depth when transplanting. Silver Bouquet and High Contrast still follow the same collar rule — leaf colour changes the look, not the centimetres.

Spacing for mature leaf and flower drift

• Blue and spotted skirts (Blue Ensign, Trevi Fountain) — often 30–45 cm between crowns for a carpet with air
• Silver faces (Majeste, Silver Bouquet) — match the same band; leave pauses so silver still reads and mildew loses a sealed canopy
• Longifolia (Bertram Anderson) — leave room for narrower upright leaves
• Pink-raspberry faces (Raspberry Splash) — match spotted skirt spacing unless the tag claims a wider clump
• Containers — one strong plant per modest pot, or a few in a wide trough with air between crowns
• Path edges — set early flowers and spots forward of taller hosta plates so spring colour reads before mid-bed leaves expand

Crowded crowns thin the spotted canopy and invite slug thatch plus mildew after dry stress. Tray spacing is not mature spacing — plant for the leaf span you want in year two and three.

Container-grown plants can go in during a mild summer if you water them through dry spells. Cool windows are still safer. Summer heat plus dry edges browns margins and invites mildew on new stock.

First-year aftercare while roots settle

Keep moisture even through the first growing season's dry spells. Flower sprays and silvering may look thin until roots claim the pocket. That is calendar, not a failed cultivar. Protect soft new leaves from slugs. Older leaves may still fade in heat; cut tired blades rather than shearing the whole clump into peak drought.

If mildew appears in year one after a dry spell, restore water and air before you dig out the plant. If margins brown while soil is dry, water and mulch. If nothing expands by midsummer in moist shade, check for sealed wet rot versus simple drought on a raised edge.

• Water when the top inch dries in heat — more often in pots
• Empty saucers after heavy rain in cool weather
• Hand-pick slugs on soft spring growth
• Do not shear the whole clump in midsummer heat
• Note which faces held clean leaves for next cool season

When to wait versus when to divide

Wait to divide until clumps are congested or the centre thins — often every three to five years, not every spring as a ritual. Divide in the same cool windows as plant-out: early spring as buds swell, or early autumn with recovery time before freeze.

Water the clump the day before. Lift with a fork. Split into pieces with buds and roots. Replant promptly into moist prepared pockets. Water through the first dry spells. Discard soft foul centres.

Silver Majeste and longifolia Bertram Anderson divisions still need spread room and air; do not cram four pieces into the space one crown owned.

Do not divide in peak summer heat. Soft cut faces in drought is how margins crisp, mildew finds stress, and crowns stall. Partners that share the bed after plant-out: Pulmonaria Companion Plants. Foliage and flower band choice before you multiply stock: Types of Pulmonaria. Shared summer water: How to Grow Pulmonaria.

Use a cool plant-out window, plant at nursery depth in moist soil, space for mature leaf spread with air, then water the first year until roots settle.