Lungwort 'Mrs Moon' (Mrs Moon Lungwort) care

Light

The Goldilocks zone. Not the south-facing windowsill (too hot, too direct), not the back of the room (too dim, growth stalls). Best in partial to full shade. The silver-spotted leaves can scorch badly in full sun, especially during hot summers. Suitable for positions under deciduous trees where it benefits from winter and early-spring sun. If you can't decide, a free phone lux-meter app aimed at the leaf at noon should read between 800 and 1,500 lux.

Watering

Watering lungwort 'mrs moon': every 5-7 days in the growing season; keep soil moist but not waterlogged. The number that matters isn't the day of the week — it's how dry the top 2-3 cm of the pot feels. A finger in the soil tells you more than a watering app. After every watering, tip the saucer. Pulmonaria requires reliably moist soil. Dry conditions cause tatty, scorch-tipped foliage and premature dormancy. Mulch heavily after planting to retain moisture.

Soil and pot

Lungwort 'Mrs Moon' grows best in humus-rich, moisture-retentive loam or clay-loam. Thrives in cool, organically enriched soil. Tolerates heavier clay soils well. Avoid thin, sandy, or very dry soils. Slightly acid to neutral pH (6.0-7.0) preferred. A pot with a working drainage hole is non-negotiable for this species — even free-draining mix will turn soggy in a closed planter. If you love the look of a decorative pot without a hole, use it as a cachepot around an inner nursery pot you can lift out to water.

Humidity and temperature

Lungwort 'Mrs Moon' sits happiest at around 50-80% humidity and -25-22°C (-13-72°F). Prefers the cool, moist atmosphere of woodland-style plantings. Low humidity combined with dry soil accelerates leaf scorch and dormancy. If you keep the room above year-round and avoid placing the plant near a cold draught, a hot radiator, or an air-conditioning vent, you have already handled the two biggest indoor stressors.

Fertilising

Feed lungwort 'mrs moon' sparingly. A spring top-dressing of balanced fertiliser or well-rotted compost is usually sufficient. Pulmonaria is not a heavy feeder; avoid nitrogen-rich feeds that promote soft, disease-prone growth at the expense of the distinctive spotted foliage. Skip fertiliser entirely on a stressed, recently-repotted, or actively wilting plant — fertiliser salts make damage worse, not better. Wait for a round of healthy new growth before resuming a feeding rhythm.

Common problems

Below are the issues we see most often on lungwort 'mrs moon' in the Growli community. Each is annotated with the most common cause so you know where to start.

• Powdery mildew — The most common problem, especially in dry or warm summers; cut back affected foliage hard after flowering and water well to encourage fresh growth.
• Vine weevil — Adults notch leaf margins; larvae damage roots. Apply nematodes in late summer.
• Leaf scorch — Direct sun, particularly in combination with dry soil, causes bleached and brown-edged foliage; move to a shadier position.
• Slug and snail damage — Young leaves are vulnerable; use appropriate controls in spring.
• Summer dormancy — Plants may look tired or go dormant in drought; consistent moisture prevents early die-back.

Companion plants

Lungwort 'Mrs Moon' pairs well with Brunnera macrophylla, Hosta, Polygonatum (Solomon's Seal), and Anemone nemorosa. These are species with similar light and water needs, so you can group them in the same room or on the same shelf and water as a batch.

Propagation

Divide clumps immediately after flowering in late spring or early summer, or in early autumn. Each division should have a strong growing point and good roots. Replant divisions promptly and water well. Propagation is the cheapest, most satisfying way to expand a collection — and it doubles as insurance against losing a mature plant to an accident. Take a backup cutting once the parent is established and healthy.

Toxicity to pets

Lungwort 'Mrs Moon' is pet-safe. Pulmonaria saccharata is listed as non-toxic to dogs, cats, and horses by the ASPCA. It is considered safe for households with pets. If you keep cats, dogs, or curious children in the house, weigh placement carefully — a high shelf or a hanging planter is enough for casual safety. For severe ingestion incidents, call your local vet and the ASPCA Animal Poison Control Center (in the US, 888-426-4435).

Pet-safety status is sourced from the ASPCA Toxic and Non-Toxic Plant List, which catalogues the most-asked-about plants for cats, dogs, and horses.

Lungwort 'Mrs Moon' deep-dive guides

Every aspect of lungwort 'mrs moon' care, each with its own calibrated guide:

• Common lungwort 'mrs moon' problems & fixes
• Lungwort 'Mrs Moon' watering schedule
• Lungwort 'Mrs Moon' light requirements
• Best soil mix for lungwort 'mrs moon'
• Lungwort 'Mrs Moon' fertilizing guide
• When to repot lungwort 'mrs moon'
• How to propagate lungwort 'mrs moon'
• How to prune lungwort 'mrs moon'
• What's eating my lungwort 'mrs moon'?
• Lungwort 'Mrs Moon' growth rate & size
• Lungwort 'Mrs Moon' cold hardiness
• Lungwort 'Mrs Moon' temperature & humidity
• Is lungwort 'mrs moon' toxic to cats & dogs?
• Is lungwort 'mrs moon' toxic to cats?
• Is lungwort 'mrs moon' toxic to dogs?
• All 9 Pulmonaria varieties
• Getting lungwort 'mrs moon' to bloom

Featured in these plant shortlists

Lungwort 'Mrs Moon' qualifies for 14 curated Growli shortlists — each one filtered objectively from our structured plant-care library, so the selection is consistent and checkable:

• Best pet-safe houseplants — Houseplants the ASPCA lists as non-toxic to cats and dogs — every one verified against the ASPCA toxic and non-toxic plant list.
• Best low-light houseplants — Houseplants that need no direct sun and cope with a north-facing room or a spot well back from a window.
• Best plants for a north-facing window — Houseplants for a north-facing window: bright, even, indirect light and no scorching direct sun. Each pick verified against its documented light needs.
• Best pet-safe low-light plants — Non-toxic to cats and dogs AND happy with no direct sun — the two hardest constraints to satisfy at once.
• Best plants for cold, dark rooms — Houseplants that cope with BOTH low light and a cool, unheated room — the hardest indoor spot to fill. Every pick tolerates a low of about 10°C and shade.
• Best humidity-loving houseplants — Houseplants that thrive in a bathroom, kitchen, or by a humidifier — selected by documented humidity preference.
• Best bathroom plants — Humidity-loving houseplants that also cope with lower light — suited to the steamy, often-dim conditions of a typical bathroom.
• Best flowering houseplants — Indoor plants grown for their blooms — selected from the flowering species in Growli’s plant-care library.
• Best pet-safe flowering plants — Flowering houseplants the ASPCA lists as non-toxic to cats and dogs — colour and blooms in a pet home, without the worry.
• Best pet-safe bathroom plants — Non-toxic to cats and dogs and happy in the humid, lower-light conditions of a bathroom — safe greenery for the smallest room.
• Best houseplants for a cool room — Houseplants that tolerate cool conditions down to about 10°C — for an unheated spare room, hallway, porch or a home kept cool.
• Best pet-safe bedroom plants — Non-toxic to cats and dogs and happy in lower light — calming greenery for a bedroom where a pet often sleeps too.
• Best cat-safe plants — Houseplants the ASPCA lists as non-toxic to cats (and dogs) — safe greenery for a home with a curious cat.
• Best dog-safe plants — Houseplants the ASPCA lists as non-toxic to dogs (and cats) — safe greenery for a home with a curious dog.
• Browse all 30 plant shortlists — pet-safe, low-light, drought-tolerant and more

Related guides

Lungwort 'Mrs Moon' is also known as Mrs Moon Lungwort, Bethlehem Sage, and Jerusalem Cowslip.

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