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Fertilising guide

How to fertilise Lance-leaved Sundew (Drosera adelae)— schedule & NPK

Also called Lance-leaved sundew, Lance-leaf sundew, Sword sundew.

More about lance-leaved sundew

About Lance-leaved Sundew

Drosera adelae · also called Lance-leaved sundew, Lance-leaf sundew · houseplant

Drosera adelae, the lance-leaved sundew, is a beginner-friendly carnivorous houseplant from Queensland, Australia. Its sword-shaped leaves are covered in glistening, sticky tentacles that trap small insects. Grow it in wet sphagnum, bright light, and pure rain or distilled water, with no dormancy. Not ASPCA-listed; treat as mildly toxic and check with a vet.

Growth habit: Low, clumping rosette of upright, sword- or lance-shaped leaves that flatten as they mature, each densely covered in red, mucilage-tipped tentacles. Readily produces plantlets along its shallow roots, slowly forming a dense colony. Evergreen and tropical, with no winter dormancy.

Watch for — 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.

What fertiliser lance-leaved sundew actually wants — and why

Lance-leaved Sundew is an easy, light foliage feeder — a half-strength balanced liquid feed through the growing months keeps it green without forcing weak, sappy growth.

A balanced general houseplant feed (roughly even N-P-K) is exactly right — it is grown for foliage, so steady, moderate nitrogen for healthy leaves is the goal, not a bloom or root formula.

For the language behind the three numbers on the bottle — what nitrogen, phosphorus and potassium each do — see the NPK ratio explained entry. The short version for lance-leaved sundew: match the feed to the job the plant is doing right now, not to a generic “plant food” on the shelf.

How often to feed lance-leaved sundew, and which months

Feeding only earns its keep while the plant is in active growth and can use the nutrients — pour feed into a dormant or low-light plant and it simply builds up as root-burning salt. For lance-leaved sundew:

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. Treat that as once a month between spring through early autumn (roughly March to September); ease off in autumn and stop entirely in the low light of winter.

The dormant-season rule matters more than the exact interval: skip feeding entirely when lance-leaved sundew is resting. For the wider context on indoor feeding rhythms across the seasons, the houseplant fertiliser schedule walks through the year month by month.

What strength to mix for lance-leaved sundew

Half strength is the safe default for lance-leaved sundew — houseplant feeds are formulated strong, and the diluted dose is gentler on the roots while still ample for foliage.

Feeding always goes onto already-damp soil, never dry roots — water lance-leaved sundew first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the lance-leaved sundew watering schedule.

Signs you are over-feeding lance-leaved sundew

Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for lance-leaved sundew:

Signs you are under-feeding lance-leaved sundew

If the symptoms point at watering, light or roots rather than nutrition, the full lance-leaved sundew care brief covers soil, humidity and the common problems for this species.

Flushing and leaching the salts

Flush the pot of lance-leaved sundew with plain water until it runs freely from the base every couple of months in the feeding season — it washes out the fertiliser salts that cause brown tips.

Organic vs synthetic feeds for lance-leaved sundew

Organic options

A diluted seaweed or worm-casting feed, or fish emulsion if you can tolerate the smell indoors. UK: Westland or Baby Bio Organic, dilute seaweed; US: Espoma Indoor! or Neptune's Harvest fish & seaweed. Slow, gentle and hard to overdo.

Synthetic / liquid feeds

A general-purpose houseplant liquid at half strength — UK: Baby Bio, Westland Houseplant Feed or Phostrogen; US: Miracle-Gro Indoor Plant Food or Schultz. Convenient and fast-acting; the only risk is overdoing it.

Brand names are examples, not endorsements, and UK and US ranges differ — check the label’s own NPK and dilution rate, since formulations change.

Fertilising lance-leaved sundew — frequently asked questions

What fertiliser does lance-leaved sundew need?

A balanced general houseplant feed (roughly even N-P-K) is exactly right — it is grown for foliage, so steady, moderate nitrogen for healthy leaves is the goal, not a bloom or root formula. Lance-leaved Sundew is an easy, light foliage feeder — a half-strength balanced liquid feed through the growing months keeps it green without forcing weak, sappy growth.

How often should I feed lance-leaved sundew?

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. 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. Treat that as once a month between spring through early autumn (roughly March to September); ease off in autumn and stop entirely in the low light of winter.

What strength of feed for lance-leaved sundew?

Half strength is the safe default for lance-leaved sundew — houseplant feeds are formulated strong, and the diluted dose is gentler on the roots while still ample for foliage.

What does over-feeding lance-leaved sundew look like?

Brown, crispy leaf tips and edges with no sign of underwatering. A white, crusty salt deposit on the soil surface or pot rim. Weak, pale, stretched new growth that flops. Lower leaves yellow and drop while the soil is correctly watered. Feeding lance-leaved sundew year-round on a fixed schedule, including dark winter months, is the most common mistake — it cannot use the nutrients in low light and the surplus simply burns the roots and crusts the soil.

Should I flush the soil of lance-leaved sundew?

Flush the pot of lance-leaved sundew with plain water until it runs freely from the base every couple of months in the feeding season — it washes out the fertiliser salts that cause brown tips.

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