Fertilising guide
How to fertilise Oxalis Vulcanicola 'Zinfandel' (Oxalis vulcanicola 'Zinfandel')— schedule & NPK
Also called Zinfandel oxalis, volcano oxalis, burgundy oxalis.
More about oxalis vulcanicola 'zinfandel'
About Oxalis Vulcanicola 'Zinfandel'
Oxalis vulcanicola 'Zinfandel' · also called Zinfandel oxalis, volcano oxalis · houseplant
Oxalis vulcanicola 'Zinfandel' is a Central American volcano sorrel grown for its deep burgundy-black, shamrock-shaped clover leaves and cheery little yellow flowers. Unlike many oxalis it does not go fully dormant, staying compact and colourful year-round in bright light. Like all Oxalis it contains soluble oxalates and is ASPCA-listed as toxic to cats and dogs.
Growth habit: Low, mounding, evergreen perennial forming a tidy clump of fine wiry stems topped with trifoliate clover leaves. It stays compact and, unlike many oxalis, does not die back to dormancy, flowering on and off through much of the year in good light.
Watch for — Leggy, floppy stems: Low light or overfeeding stretches the plant. Increase light, trim back leggy growth, and feed only lightly to maintain a dense, well-coloured clump.
What fertiliser oxalis vulcanicola 'zinfandel' actually wants — and why
Oxalis Vulcanicola 'Zinfandel' is a genuinely hungry tropical — in bright warmth it pushes growth fast and rewards a regular half-strength balanced feed all season.
A balanced liquid feed (even N-P-K) or a slightly nitrogen-leaning foliage feed — this is a big-leaved foliage plant putting on real size, so it wants steady nitrogen for lush leaves, not a bloom 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 oxalis vulcanicola 'zinfandel': 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 oxalis vulcanicola 'zinfandel', 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 oxalis vulcanicola 'zinfandel':
Feed every 3-4 weeks during spring and summer with a balanced liquid houseplant fertiliser at half strength to sustain colour and flowering. Ease off in autumn and winter. It is not a heavy feeder; over-fertilising promotes soft, leggy green growth at the expense of the rich burgundy tone. For a fast grower like this that means feeding regularly — about every 3-4 weeks — right through spring through early autumn (roughly March to September), tapering off only as light drops in autumn.
The dormant-season rule matters more than the exact interval: skip feeding entirely when oxalis vulcanicola 'zinfandel' 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 oxalis vulcanicola 'zinfandel'
Half strength every feed is the sweet spot for oxalis vulcanicola 'zinfandel': frequent enough to fuel fast growth, dilute enough that it never scorches even when you feed often.
Feeding always goes onto already-damp soil, never dry roots — water oxalis vulcanicola 'zinfandel' first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the oxalis vulcanicola 'zinfandel' watering schedule.
Signs you are over-feeding oxalis vulcanicola 'zinfandel'
Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for oxalis vulcanicola 'zinfandel':
- Brown, scorched leaf tips and margins despite correct watering.
- A white salt crust on the soil or around the pot edge.
- Sudden leaf yellowing and drop shortly after a strong feed.
- Soft, weak, over-stretched growth that cannot support itself.
Signs you are under-feeding oxalis vulcanicola 'zinfandel'
- New leaves coming in noticeably smaller than older ones.
- Pale, yellow-green older leaves and slow growth through peak summer.
- A general loss of vigour and gloss in a plant that should be racing away.
If the symptoms point at watering, light or roots rather than nutrition, the full oxalis vulcanicola 'zinfandel' care brief covers soil, humidity and the common problems for this species.
Flushing and leaching the salts
Because you feed often, salts accumulate faster — flush the pot of oxalis vulcanicola 'zinfandel' with plain water until it drains freely roughly every month through the feeding season to keep the root zone clean.
Organic vs synthetic feeds for oxalis vulcanicola 'zinfandel'
Organic options
A diluted seaweed or fish-and-seaweed feed plus a yearly top-dress of worm castings supports fast growth without burn risk. UK: Westland seaweed or Baby Bio Organic; US: Neptune's Harvest or Espoma Indoor!.
Synthetic / liquid feeds
A balanced houseplant liquid at half strength applied frequently — UK: Baby Bio, Phostrogen or Westland Houseplant Feed; US: Miracle-Gro Indoor Plant Food or Dyna-Gro Foliage-Pro for steady leafy growth.
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 oxalis vulcanicola 'zinfandel' — frequently asked questions
What fertiliser does oxalis vulcanicola 'zinfandel' need?
A balanced liquid feed (even N-P-K) or a slightly nitrogen-leaning foliage feed — this is a big-leaved foliage plant putting on real size, so it wants steady nitrogen for lush leaves, not a bloom formula. Oxalis Vulcanicola 'Zinfandel' is a genuinely hungry tropical — in bright warmth it pushes growth fast and rewards a regular half-strength balanced feed all season.
How often should I feed oxalis vulcanicola 'zinfandel'?
Feed every 3-4 weeks during spring and summer with a balanced liquid houseplant fertiliser at half strength to sustain colour and flowering. Ease off in autumn and winter. It is not a heavy feeder; over-fertilising promotes soft, leggy green growth at the expense of the rich burgundy tone. Feed every 3-4 weeks during spring and summer with a balanced liquid houseplant fertiliser at half strength to sustain colour and flowering. Ease off in autumn and winter. It is not a heavy feeder; over-fertilising promotes soft, leggy green growth at the expense of the rich burgundy tone. For a fast grower like this that means feeding regularly — about every 3-4 weeks — right through spring through early autumn (roughly March to September), tapering off only as light drops in autumn.
What strength of feed for oxalis vulcanicola 'zinfandel'?
Half strength every feed is the sweet spot for oxalis vulcanicola 'zinfandel': frequent enough to fuel fast growth, dilute enough that it never scorches even when you feed often.
What does over-feeding oxalis vulcanicola 'zinfandel' look like?
Brown, scorched leaf tips and margins despite correct watering. A white salt crust on the soil or around the pot edge. Sudden leaf yellowing and drop shortly after a strong feed. Soft, weak, over-stretched growth that cannot support itself. The mistake here is the opposite of most houseplants: under-feeding a fast tropical in peak season starves it, leaving small, pale new leaves and slow growth — but full-strength doses still burn it, so feed often and weak, not occasionally and strong.
Should I flush the soil of oxalis vulcanicola 'zinfandel'?
Because you feed often, salts accumulate faster — flush the pot of oxalis vulcanicola 'zinfandel' with plain water until it drains freely roughly every month through the feeding season to keep the root zone clean.
Keep reading
- Oxalis Vulcanicola 'Zinfandel' care — the full brief (light, soil, humidity, problems, pet safety)
- How often to water oxalis vulcanicola 'zinfandel' — 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 5561 fertilising guides in the Growli library