Fertilising guide
How to fertilise Star Jasmine (Trachelospermum jasminoides)— schedule & NPK
Also called Confederate Jasmine, Star Jasmine.
More about star jasmine
About Star Jasmine
Trachelospermum jasminoides · also called Confederate Jasmine, Star Jasmine · flowering
Star jasmine is a vigorous evergreen twining climber, not a true jasmine, prized for glossy dark foliage and masses of fragrant, pinwheel-shaped white flowers in early to midsummer. It clothes walls, fences and pergolas, tolerates sun or part shade, and is moderately hardy in mild temperate gardens. The stems exude milky sap when cut.
Growth habit: Twining, self-supporting once started, evergreen climber that needs wires or trellis to scramble up; can also be used as ground cover. Glossy leaves take bronze tints in winter cold. Bears highly fragrant white star-shaped flowers in early to midsummer. Prune lightly after flowering to shape.
Watch for — Yellowing leaves: Overwatering, poor drainage or nutrient deficiency cause yellowing. Improve drainage, let soil dry slightly between waterings, and feed in spring; use chelated iron if veins stay green.
What fertiliser star jasmine actually wants — and why
Star Jasmine is a heavy-blooming flower with a big appetite — a regular high-potash feed through the season is what drives a long, dense display.
A high-potassium ("high-potash") flowering feed — tomato-style or a dedicated bloom/rose feed. Potassium powers flowering; a high-nitrogen feed gives you a leafy plant with disappointing bloom.
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 star jasmine: 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 star jasmine, 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 star jasmine:
Feed in spring with a balanced general fertiliser and apply a high-potash feed during the flowering period to support blooming. Mulch annually with compost. Container plants benefit from a controlled-release feed in spring plus liquid feeding through summer. For a hungry bloomer that means feeding regularly — sparingly through the growing season — right through flowering across the main season (spring through early autumn), tapering as blooming ends.
The dormant-season rule matters more than the exact interval: skip feeding entirely when star jasmine 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 star jasmine
Follow the flowering-feed label rate for star jasmine, or half strength if feeding very frequently. These plants genuinely use the nutrients — under-feeding shows up fast as a thin display.
Feeding always goes onto already-damp soil, never dry roots — water star jasmine first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the star jasmine watering schedule.
Signs you are over-feeding star jasmine
Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for star jasmine:
- Lots of lush leaves but few flowers (too much nitrogen).
- Scorched leaf edges and salt crust from too-strong or too-frequent feeds.
- Soft, sappy growth prone to aphids and mildew.
Signs you are under-feeding star jasmine
- Sparse, small, short-lived flowers and pale foliage.
- A tired plant that stops blooming early in the season.
- Weak growth and poor repeat-flowering after the first flush.
If the symptoms point at watering, light or roots rather than nutrition, the full star jasmine care brief covers soil, humidity and the common problems for this species.
Flushing and leaching the salts
Container-grown star jasmine accumulates feed salts fast with frequent feeding — water until it drains each time and flush pots with plain water every few weeks to prevent scorch.
Organic vs synthetic feeds for star jasmine
Organic options
A liquid comfrey or seaweed feed (naturally potassium-rich) plus compost or well-rotted manure as a mulch. UK: comfrey feed, organic Tomorite, or rose feed; US: Espoma Rose-tone or Neptune's Harvest. Feeds and improves soil.
Synthetic / liquid feeds
A high-potash flowering feed on a regular cadence — UK: Tomorite (Levington), Phostrogen or a specialist rose feed; US: Miracle-Gro Bloom Booster or a rose food. Fast, reliable bloom response.
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 star jasmine — frequently asked questions
What fertiliser does star jasmine need?
A high-potassium ("high-potash") flowering feed — tomato-style or a dedicated bloom/rose feed. Potassium powers flowering; a high-nitrogen feed gives you a leafy plant with disappointing bloom. Star Jasmine is a heavy-blooming flower with a big appetite — a regular high-potash feed through the season is what drives a long, dense display.
How often should I feed star jasmine?
Feed in spring with a balanced general fertiliser and apply a high-potash feed during the flowering period to support blooming. Mulch annually with compost. Container plants benefit from a controlled-release feed in spring plus liquid feeding through summer. Feed in spring with a balanced general fertiliser and apply a high-potash feed during the flowering period to support blooming. Mulch annually with compost. Container plants benefit from a controlled-release feed in spring plus liquid feeding through summer. For a hungry bloomer that means feeding regularly — sparingly through the growing season — right through flowering across the main season (spring through early autumn), tapering as blooming ends.
What strength of feed for star jasmine?
Follow the flowering-feed label rate for star jasmine, or half strength if feeding very frequently. These plants genuinely use the nutrients — under-feeding shows up fast as a thin display.
What does over-feeding star jasmine look like?
Lots of lush leaves but few flowers (too much nitrogen). Scorched leaf edges and salt crust from too-strong or too-frequent feeds. Soft, sappy growth prone to aphids and mildew. Using a high-nitrogen general feed on star jasmine is the headline mistake — you grow a big leafy plant with few flowers. The second is simply under-feeding a genuinely hungry bloomer and getting a sparse, short display.
Should I flush the soil of star jasmine?
Container-grown star jasmine accumulates feed salts fast with frequent feeding — water until it drains each time and flush pots with plain water every few weeks to prevent scorch.
Keep reading
- Star Jasmine care — the full brief (light, soil, humidity, problems, pet safety)
- How often to water star jasmine — 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 peace lily
- How to fertilise bird of paradise
- How to fertilise hoya
- All 1284 fertilising guides in the Growli library