Fertilising guide
How to fertilise String of dolphins (Senecio peregrinus)— schedule & NPK
Also called dolphin plant, flying dolphins.
About String of dolphins
Senecio peregrinus · also called dolphin plant, flying dolphins · houseplant
String of dolphins is a quirky succulent hybrid with leaves shaped like leaping dolphins. A cross between string of pearls and Senecio articulatus. Mildly toxic to pets like its parents and demands bright light to keep its distinctive leaf shape.
Curio x peregrinus (Senecio x peregrinus), not a wild species but an intergeneric hybrid of Curio rowleyanus (string of pearls) and a Curio articulatus relative; the leaves curve into two small points resembling leaping dolphins.
Feed only sparingly with diluted succulent fertilizer (roughly early spring and again at bloom); overfeeding causes loss of the distinctive dolphin leaf form.
Growth habit: Trailing succulent
Sources: en.wikipedia.org, plants.ces.ncsu.edu
What fertiliser string of dolphins actually wants — and why
String of dolphins is a light-feeding succulent — a gentle, low-nitrogen feed a few times in growth keeps it plump without forcing the weak, stretched growth over-feeding causes.
A cactus and succulent formula or a diluted balanced feed with modest, even numbers. Avoid high-nitrogen plant foods — they make a succulent etiolate and grow soft, fracture-prone tissue.
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 string of dolphins: 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 string of dolphins, 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 string of dolphins:
Quarter-strength succulent feed monthly in spring and summer. Keep that to monthly between spring through early autumn (roughly March to September) and stop entirely once growth slows for winter.
The dormant-season rule matters more than the exact interval: skip feeding entirely when string of dolphins 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 string of dolphins
Quarter to half strength at most for string of dolphins. Succulents take up very little, and a strong dose burns the fine roots before the plant can use it.
Feeding always goes onto already-damp soil, never dry roots — water string of dolphins first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the string of dolphins watering schedule.
Signs you are over-feeding string of dolphins
Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for string of dolphins:
- Stretched, leggy, pale growth with widely spaced leaves.
- A white salt crust on the soil or around the pot rim.
- Brown, crisped leaf tips and edges.
- Soft, mushy tissue at the base — over-feeding plus damp soil rots it.
Signs you are under-feeding string of dolphins
- Uncommon — succulents tolerate lean conditions well.
- Very slow growth and dull, faded colour over a long period.
- Older leaves shed faster than new ones replace them in a tired old mix.
If the symptoms point at watering, light or roots rather than nutrition, the full string of dolphins care brief covers soil, humidity and the common problems for this species.
Flushing and leaching the salts
Feed lightly enough and you rarely need to flush, but once a year run plain water through the pot of string of dolphins until it drains clear, and refresh the gritty mix every 2-3 years.
Organic vs synthetic feeds for string of dolphins
Organic options
A heavily diluted seaweed or worm-casting feed once or twice in summer. UK: a drop of Westland seaweed feed; US: quarter-strength Espoma Cactus! or Dr. Earth liquid. Fresh free-draining mix matters more than any feed.
Synthetic / liquid feeds
A dedicated cactus/succulent liquid at quarter to half strength — UK: Baby Bio Cacti & Succulent Drip Feeders or Westland; US: Miracle-Gro Succulent Plant Food or Schultz Cactus Plus.
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 string of dolphins — frequently asked questions
What fertiliser does string of dolphins need?
A cactus and succulent formula or a diluted balanced feed with modest, even numbers. Avoid high-nitrogen plant foods — they make a succulent etiolate and grow soft, fracture-prone tissue. String of dolphins is a light-feeding succulent — a gentle, low-nitrogen feed a few times in growth keeps it plump without forcing the weak, stretched growth over-feeding causes.
How often should I feed string of dolphins?
Quarter-strength succulent feed monthly in spring and summer. Quarter-strength succulent feed monthly in spring and summer. Keep that to monthly between spring through early autumn (roughly March to September) and stop entirely once growth slows for winter.
What strength of feed for string of dolphins?
Quarter to half strength at most for string of dolphins. Succulents take up very little, and a strong dose burns the fine roots before the plant can use it.
What does over-feeding string of dolphins look like?
Stretched, leggy, pale growth with widely spaced leaves. A white salt crust on the soil or around the pot rim. Brown, crisped leaf tips and edges. Soft, mushy tissue at the base — over-feeding plus damp soil rots it. Feeding string of dolphins like a leafy houseplant is the classic error — it produces a flush of pale, stretched, floppy growth that never firms up and is prone to rot at the base.
Should I flush the soil of string of dolphins?
Feed lightly enough and you rarely need to flush, but once a year run plain water through the pot of string of dolphins until it drains clear, and refresh the gritty mix every 2-3 years.
Keep reading
- String of dolphins care — the full brief (light, soil, humidity, problems, pet safety)
- How often to water string of dolphins — the watering schedule
- The houseplant fertiliser schedule — feeding through the year
- NPK ratio explained — what the three numbers on the bottle mean
- How to fertilise snake plant
- How to fertilise dracaena
- How to fertilise peperomia
- All 200 fertilising guides in the Growli library