Fertilising guide
How to fertilise Laurel Clockvine (Thunbergia laurifolia)— schedule & NPK
Also called Laurel Clockvine, Blue Trumpet Vine, Blue Thunbergia.
More about laurel clockvine
About Laurel Clockvine
Thunbergia laurifolia · also called Laurel Clockvine, Blue Trumpet Vine · tropical
Thunbergia laurifolia is a powerfully vigorous tropical vine from India and Southeast Asia bearing lavender-blue trumpet flowers with a pale yellow throat. A fast grower capable of covering large structures, it is grown as a conservatory climber or warm-climate garden vine. Regarded as invasive in parts of Australia and South America.
Growth habit: Vigorous evergreen perennial twining vine; can reach tree canopy level in tropical conditions
What fertiliser laurel clockvine actually wants — and why
Laurel Clockvine is an easy, light foliage feeder — a half-strength balanced liquid feed through the growing months keeps it green without forcing weak, sappy growth.
A balanced general houseplant feed (roughly even N-P-K) is exactly right — it is grown for foliage, so steady, moderate nitrogen for healthy leaves is the goal, not a bloom or root 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 laurel clockvine: 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 laurel clockvine, 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 laurel clockvine:
Feed with a balanced liquid fertiliser every 2–3 weeks during the growing season (spring to autumn). A fertiliser with moderate nitrogen and higher potassium (such as 5-5-10) supports flowering. No feeding necessary in winter. Treat that as sparingly through the growing season between spring through early autumn (roughly March to September); ease off in autumn and stop entirely in the low light of winter.
The dormant-season rule matters more than the exact interval: skip feeding entirely when laurel clockvine 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 laurel clockvine
Half strength is the safe default for laurel clockvine — houseplant feeds are formulated strong, and the diluted dose is gentler on the roots while still ample for foliage.
Feeding always goes onto already-damp soil, never dry roots — water laurel clockvine first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the laurel clockvine watering schedule.
Signs you are over-feeding laurel clockvine
Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for laurel clockvine:
- Brown, crispy leaf tips and edges with no sign of underwatering.
- A white, crusty salt deposit on the soil surface or pot rim.
- Weak, pale, stretched new growth that flops.
- Lower leaves yellow and drop while the soil is correctly watered.
Signs you are under-feeding laurel clockvine
- Uniformly pale or yellow-green leaves, oldest first.
- Noticeably small new leaves and stalled growth in good light and season.
- A generally tired, lacklustre look despite correct watering and light.
If the symptoms point at watering, light or roots rather than nutrition, the full laurel clockvine care brief covers soil, humidity and the common problems for this species.
Flushing and leaching the salts
Flush the pot of laurel clockvine with plain water until it runs freely from the base every couple of months in the feeding season — it washes out the fertiliser salts that cause brown tips.
Organic vs synthetic feeds for laurel clockvine
Organic options
A diluted seaweed or worm-casting feed, or fish emulsion if you can tolerate the smell indoors. UK: Westland or Baby Bio Organic, dilute seaweed; US: Espoma Indoor! or Neptune's Harvest fish & seaweed. Slow, gentle and hard to overdo.
Synthetic / liquid feeds
A general-purpose houseplant liquid at half strength — UK: Baby Bio, Westland Houseplant Feed or Phostrogen; US: Miracle-Gro Indoor Plant Food or Schultz. Convenient and fast-acting; the only risk is overdoing it.
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 laurel clockvine — frequently asked questions
What fertiliser does laurel clockvine need?
A balanced general houseplant feed (roughly even N-P-K) is exactly right — it is grown for foliage, so steady, moderate nitrogen for healthy leaves is the goal, not a bloom or root formula. Laurel Clockvine is an easy, light foliage feeder — a half-strength balanced liquid feed through the growing months keeps it green without forcing weak, sappy growth.
How often should I feed laurel clockvine?
Feed with a balanced liquid fertiliser every 2–3 weeks during the growing season (spring to autumn). A fertiliser with moderate nitrogen and higher potassium (such as 5-5-10) supports flowering. No feeding necessary in winter. Feed with a balanced liquid fertiliser every 2–3 weeks during the growing season (spring to autumn). A fertiliser with moderate nitrogen and higher potassium (such as 5-5-10) supports flowering. No feeding necessary in winter. Treat that as sparingly through the growing season between spring through early autumn (roughly March to September); ease off in autumn and stop entirely in the low light of winter.
What strength of feed for laurel clockvine?
Half strength is the safe default for laurel clockvine — houseplant feeds are formulated strong, and the diluted dose is gentler on the roots while still ample for foliage.
What does over-feeding laurel clockvine look like?
Brown, crispy leaf tips and edges with no sign of underwatering. A white, crusty salt deposit on the soil surface or pot rim. Weak, pale, stretched new growth that flops. Lower leaves yellow and drop while the soil is correctly watered. Feeding laurel clockvine year-round on a fixed schedule, including dark winter months, is the most common mistake — it cannot use the nutrients in low light and the surplus simply burns the roots and crusts the soil.
Should I flush the soil of laurel clockvine?
Flush the pot of laurel clockvine with plain water until it runs freely from the base every couple of months in the feeding season — it washes out the fertiliser salts that cause brown tips.
Keep reading
- Laurel Clockvine care — the full brief (light, soil, humidity, problems, pet safety)
- How often to water laurel clockvine — 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 succulentum pachypodium
- How to fertilise madagascar palm geay
- How to fertilise horombe pachypodium
- All 8452 fertilising guides in the Growli library