Fertilising guide
How to fertilise Purple Wreath (Petrea volubilis)— schedule & NPK
Also called Purple Wreath, Queen's Wreath, Sandpaper Vine, Blue Petrea.
More about purple wreath
About Purple Wreath
Petrea volubilis · also called Purple Wreath, Queen's Wreath · tropical
A spectacular flowering tropical vine from Central America and the Caribbean, bearing foot-long racemes of star-like violet flowers that rival wisteria in impact. The rough, sandpaper-textured leaves give it an alternative common name. Fast-growing and floriferous in full sun, it thrives in USDA zones 10–11 and tolerates brief light frost when established.
Growth habit: Fast-growing woody twining vine; can be trained as a large shrub or espalier
What fertiliser purple wreath actually wants — and why
Purple Wreath 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 purple wreath: 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 purple wreath, 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 purple wreath:
Feed monthly during the growing season with a balanced slow-release fertiliser, or apply a liquid balanced fertiliser every 2–4 weeks from spring through summer. Compost or well-rotted manure applied as a mulch in spring also benefits this heavy feeder. For a fast grower like this that means feeding regularly — about monthly — 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 purple wreath 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 purple wreath
Half strength every feed is the sweet spot for purple wreath: 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 purple wreath first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the purple wreath watering schedule.
Signs you are over-feeding purple wreath
Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for purple wreath:
- 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 purple wreath
- 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 purple wreath 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 purple wreath 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 purple wreath
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 purple wreath — frequently asked questions
What fertiliser does purple wreath 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. Purple Wreath 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 purple wreath?
Feed monthly during the growing season with a balanced slow-release fertiliser, or apply a liquid balanced fertiliser every 2–4 weeks from spring through summer. Compost or well-rotted manure applied as a mulch in spring also benefits this heavy feeder. Feed monthly during the growing season with a balanced slow-release fertiliser, or apply a liquid balanced fertiliser every 2–4 weeks from spring through summer. Compost or well-rotted manure applied as a mulch in spring also benefits this heavy feeder. For a fast grower like this that means feeding regularly — about monthly — right through spring through early autumn (roughly March to September), tapering off only as light drops in autumn.
What strength of feed for purple wreath?
Half strength every feed is the sweet spot for purple wreath: frequent enough to fuel fast growth, dilute enough that it never scorches even when you feed often.
What does over-feeding purple wreath 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 purple wreath?
Because you feed often, salts accumulate faster — flush the pot of purple wreath with plain water until it drains freely roughly every month through the feeding season to keep the root zone clean.
Keep reading
- Purple Wreath care — the full brief (light, soil, humidity, problems, pet safety)
- How often to water purple wreath — 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 anthurium andraeanum 'kozohara'
- How to fertilise anthurium andraeanum 'midori'
- How to fertilise anthurium andraeanum 'president'
- All 8452 fertilising guides in the Growli library