Lance-leaved Sundew (Lance-leaf sundew) care

Light

Bright but filtered. Lance-leaved Sundew burns within days in unfiltered south-facing summer sun, and stops growing within months in deep shade. Bright light is essential. On a windowsill use an east window in summer and a south window in winter; under grow lights give 8-12 hours daily. Strong light turns the tentacles pink-to-red and keeps the plant compact and dewy; low light produces long, pale, dew-poor leaves. Avoid harsh midday sun behind glass, which can scorch and overheat the wet media. If you only have a south window, set the plant back 1.5 m or hang a sheer curtain — both knock the intensity down into the right range.

Watering

Watering lance-leaved sundew: keep permanently wet via the tray method (1-2 inches of standing water); never let the media dry out. 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. Use ONLY rainwater, distilled, or reverse-osmosis water. Tap and mineral water build up salts that kill sundews. D. adelae is forgiving of water level as long as the sphagnum stays saturated, so a humidity tray that you keep topped up works well year-round.

Soil and pot

Lance-leaved Sundew grows best in pure long-fibred sphagnum moss (or a 1:1 peat-and-perlite/silica-sand carnivorous mix). Use only nutrient-free, lime-free media; never standard potting soil or fertiliser-enriched compost, which burns the roots. Long-fibred sphagnum is the preferred medium; a peat moss and washed silica sand or perlite blend also works. Pot at least 5 inches tall to hold moisture and the spreading root system. 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

Lance-leaved Sundew sits happiest at around Around 40-70%; tolerates 30% in cooler conditions humidity and 13-29C (55-85F). Higher humidity (50-70%) gives the best dew, but D. adelae adapts to average household humidity near 40% as long as the media stays wet. Below about 70F it copes with humidity as low as 30%; above 75F it needs 50%+ to avoid drying out. The constantly wet tray naturally raises humidity around the plant. If you keep the room above 13 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 lance-leaved sundew sparingly. Do not use root fertiliser; it kills carnivorous plants. The plant gets its nutrients from prey. Indoors it usually catches enough gnats and fruit flies on its own; if not, you can feed an occasional small insect (a fruit fly, gnat, or rehydrated bloodworm) to one or two leaves about once a month. Never feed meat, and don't overfeed, as rotting prey can cause leaves to blacken. 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 lance-leaved sundew in the Growli community. Each is annotated with the most common cause so you know where to start.

• No dew on the tentacles — The signature sticky droplets fail to form in low light, low humidity, or dry media. Move to brighter light, keep the sphagnum saturated, and raise humidity; new dewy leaves should follow within a couple of weeks.
• Leaves go long, green, and floppy — Stretched, pale, dew-poor leaves with no red colour mean insufficient light. Give brighter light or 8-12 hours under a grow light to restore compact, reddish, well-armed growth.
• Brown crispy leaf tips or sudden decline — Almost always mineral burn from tap or bottled mineral water, or fertiliser contact. Switch to rainwater/distilled/RO water only and flush the media; never use enriched potting soil or feed root fertiliser.
• Blackening leaves — Caused by overfeeding (rotting prey), letting the media dry out, or cold/heat stress. Remove rotting leaves, keep media wet, hold 55-85F, and feed only tiny insects sparingly.
• Top growth dies back in cold or dry spells — D. adelae has no true dormancy but upper leaves can die off in cold, dry conditions while the roots survive. Keep it above freezing, maintain moisture, and it typically regrows plantlets from the roots.
• Fungus gnats or mould on wet media — Constantly wet sphagnum can grow surface mould or attract fungus gnats. Improve airflow and light; the plant itself often catches the adult gnats, and good ventilation keeps mould in check.

Propagation

Easiest from leaf cuttings: lay a healthy leaf on damp sphagnum or float it on pure water in bright, humid conditions, and numerous plantlets (up to a couple of dozen from one leaf) will sprout in a few weeks. It also spreads naturally by root plantlets, which can be lifted and potted, and can be increased by division of an established clump. 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

Lance-leaved Sundew is mildly toxic to pets. Drosera adelae is NOT individually listed in the ASPCA toxic/non-toxic plant database, and the ASPCA lists no Drosera (sundew) species at all; the only ASPCA-listed Droseraceae member is the Venus flytrap (a different genus, Dionaea), rated non-toxic. Because the sundew genus itself is unverified and some Drosera contain the irritant plumbagin, treat it conservatively as mildly toxic, where ingestion may cause mild mouth irritation or gastrointestinal upset, and verify with your vet or the ASPCA hotline before assuming it is safe. 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.

Lance-leaved Sundew deep-dive guides

Every aspect of lance-leaved sundew care, each with its own calibrated guide:

• Lance-leaved Sundew watering schedule
• Lance-leaved Sundew light requirements
• Best soil mix for lance-leaved sundew
• Lance-leaved Sundew fertilizing guide
• When to repot lance-leaved sundew
• How to propagate lance-leaved sundew
• Lance-leaved Sundew growth rate & size
• Lance-leaved Sundew cold hardiness
• Lance-leaved Sundew temperature & humidity
• Is lance-leaved sundew toxic to cats & dogs?

Related guides

Lance-leaved Sundew is also known as Lance-leaved sundew, Lance-leaf sundew, and Sword sundew.

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