Fertilising guide

How to fertilise Cyclamen (Cyclamen persicum)— schedule & NPK

Also called Cyclamen, Persian cyclamen, Florist's cyclamen, Sowbread.

More about cyclamen

About Cyclamen

Cyclamen persicum · also called Cyclamen, Persian cyclamen · flowering

Cyclamen persicum is a cool-loving, winter-blooming flowering houseplant with marbled, heart-shaped leaves and upswept petals. It needs bright indirect light, cool rooms, and careful below-pot watering to protect its tuber. The ASPCA lists Cyclamen as toxic to dogs and cats, so keep it out of reach of pets.

Growth habit: Tuberous herbaceous perennial grown as a winter-flowering pot plant. It forms a low mound of marbled, heart-shaped leaves with butterfly-like flowers held on upright stems above the foliage. After blooming it goes dormant for 6-8 weeks in late spring to summer, dying back to the tuber before regrowing.

Watch for — Cyclamen and spider mites: Microscopic mites cause curled, distorted, discoloured leaves and stunted buds, and thrive in dry air. Raise humidity and keep rooms cool; infestations are hard to eradicate, so prevention is key.

What fertiliser cyclamen actually wants — and why

Cyclamen 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 cyclamen: 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 cyclamen, 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 cyclamen:

Feed every two weeks while in active growth and bloom with a dilute, low-nitrogen liquid fertiliser (a higher-phosphorus bloom feed works well). Stop feeding once the plant begins its summer dormancy and leaves yellow. The pattern that matters: feed little and often through active growth and budding — sparingly through the growing season — 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 cyclamen 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 cyclamen

Very dilute — quarter strength, the classic "weakly, weekly" approach for cyclamen. 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 cyclamen first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the cyclamen watering schedule.

Signs you are over-feeding cyclamen

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

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 cyclamen

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 cyclamen 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 cyclamen 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 cyclamen

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 cyclamen — frequently asked questions

What fertiliser does cyclamen 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. Cyclamen 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 cyclamen?

Feed every two weeks while in active growth and bloom with a dilute, low-nitrogen liquid fertiliser (a higher-phosphorus bloom feed works well). Stop feeding once the plant begins its summer dormancy and leaves yellow. Feed every two weeks while in active growth and bloom with a dilute, low-nitrogen liquid fertiliser (a higher-phosphorus bloom feed works well). Stop feeding once the plant begins its summer dormancy and leaves yellow. The pattern that matters: feed little and often through active growth and budding — sparingly through the growing season — and ease right off during the rest period that triggers the next flush.

What strength of feed for cyclamen?

What does over-feeding cyclamen 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 cyclamen 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 cyclamen?