Fertilising guide

How to fertilise Large-Leaved Butterwort (Pinguicula macrophylla)— schedule & NPK

Also called Large-leaved butterwort, Mexican butterwort.

More about large-leaved butterwort

About Large-Leaved Butterwort

Pinguicula macrophylla · also called Large-leaved butterwort, Mexican butterwort · houseplant

Pinguicula macrophylla is an unusual carnivorous butterwort endemic to Guanajuato, Mexico, notable for its large oval carnivorous leaves borne on distinctive long petioles (leaf stalks) in summer — a feature that sets it apart from most other Mexican Pinguicula. In winter it retreats to a bulb-like dormant bud at the soil surface, and the critical care point is to allow the substrate to dry out significantly during this rest phase. It is not confirmed as non-toxic on the ASPCA database and carries a precautionary mildly-toxic rating.

Growth habit: Petiolate rosette with large, oval, glandular leaves on distinct stalks in summer; retreats to a compact bulb-like dormant bud at the soil surface in winter.

What fertiliser large-leaved butterwort actually wants — and why

Large-Leaved Butterwort is feeding to flower, not to grow leaves — it needs a higher-phosphorus / specialist bloom feed, given little and often, to set and hold its display.

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 large-leaved butterwort: 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 large-leaved butterwort, 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 large-leaved butterwort:

Feed small insects or dried bloodworms placed on the sticky leaves every 2-3 weeks during the carnivorous summer season; alternatively, apply a very dilute foliar fertiliser (quarter-strength, low-nitrogen orchid feed) to the leaves only. The pattern that matters: feed little and often through active growth and budding — every 2-3 weeks — and ease right off during the rest period that triggers the next flush.

The dormant-season rule matters more than the exact interval: skip feeding entirely when large-leaved butterwort 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 large-leaved butterwort

Very dilute — quarter strength, the classic "weakly, weekly" approach for large-leaved butterwort. These plants have fine roots that scorch easily and a steady trickle beats an occasional strong dose for flowering.

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

Signs you are over-feeding large-leaved butterwort

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

Lush green leaves but few or no flowers (too much nitrogen).
Brown, scorched leaf tips and edges — a classic fine-root burn.
White salt crust on the medium or pot, and stalled buds.
Bud blast: buds forming then shrivelling and dropping.

Signs you are under-feeding large-leaved butterwort

Sparse or no flowering despite good light and the right season.
Smaller, paler new leaves and a generally weak, tired plant.
Flowers that are smaller or fade faster than they should.

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

Flushing and leaching the salts

Specialist and bloom feeds leave salts that scorch fine roots — flush large-leaved butterwort thoroughly with plain water until it runs clear every 4-6 weeks in the feeding season, and always between feeds for orchids.

Organic vs synthetic feeds for large-leaved butterwort

Organic options

Gentler options exist: a dilute seaweed feed (mildly potassium-rich) or worm-casting tea. UK: Westland seaweed, or a dilute tomato feed like Tomorite for bud-formers; US: Espoma Orchid! / Violet! or Neptune's Harvest. Lower burn risk, slower response.

Synthetic / liquid feeds

A species-matched bloom feed at quarter strength — UK: Baby Bio Orchid / African Violet food, or a high-potash Tomorite/Phostrogen for budding bloomers; US: Miracle-Gro Orchid or Bloom Booster, Schultz African Violet.

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 large-leaved butterwort — frequently asked questions

What fertiliser does large-leaved butterwort need?

A higher-phosphorus "bloom" formula or a species-specific feed (orchid food, African violet food, or a tomato-style high-potash/phosphorus liquid). A high-nitrogen general feed gives you lush leaves and almost no flowers. Large-Leaved Butterwort is feeding to flower, not to grow leaves — it needs a higher-phosphorus / specialist bloom feed, given little and often, to set and hold its display.

How often should I feed large-leaved butterwort?

Feed small insects or dried bloodworms placed on the sticky leaves every 2-3 weeks during the carnivorous summer season; alternatively, apply a very dilute foliar fertiliser (quarter-strength, low-nitrogen orchid feed) to the leaves only. Feed small insects or dried bloodworms placed on the sticky leaves every 2-3 weeks during the carnivorous summer season; alternatively, apply a very dilute foliar fertiliser (quarter-strength, low-nitrogen orchid feed) to the leaves only. The pattern that matters: feed little and often through active growth and budding — every 2-3 weeks — and ease right off during the rest period that triggers the next flush.

What strength of feed for large-leaved butterwort?

What does over-feeding large-leaved butterwort look like?

Lush green leaves but few or no flowers (too much nitrogen). Brown, scorched leaf tips and edges — a classic fine-root burn. White salt crust on the medium or pot, and stalled buds. Bud blast: buds forming then shrivelling and dropping. Using an ordinary high-nitrogen houseplant feed on large-leaved butterwort is the headline mistake — you get a healthy-looking plant that simply refuses to bloom. The second is feeding through the rest period and breaking the dormancy cue it needs to set buds.

Should I flush the soil of large-leaved butterwort?