Fertilising guide
How to fertilise Painted Nettle (Plectranthus scutellarioides)— schedule & NPK
Also called Painted Nettle, Coleus, Flame Nettle.
More about painted nettle
About Painted Nettle
Plectranthus scutellarioides · also called Painted Nettle, Coleus · tropical
Plectranthus scutellarioides (syn. Coleus scutellarioides) is a fast-growing tropical foliage plant from Southeast Asia and the Pacific, grown for its brilliantly coloured leaves in combinations of red, orange, yellow, pink, purple, and green. It thrives in bright, indirect light and consistently moist, well-drained compost, and grows rapidly in warmth and humidity. Pinching out flower spikes as soon as they appear prolongs the vivid leaf colour and prevents premature decline. Toxic to cats, dogs, and horses.
Growth habit: Upright to slightly bushy, soft-stemmed tropical perennial or annual with square stems typical of the mint family (Lamiaceae); grows rapidly and benefits from regular pinching to stay compact.
What fertiliser painted nettle actually wants — and why
Painted Nettle 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 painted nettle: 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 painted nettle, 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 painted nettle:
Feed every 2 weeks during spring and summer with a balanced liquid fertiliser; a formulation with slightly elevated nitrogen supports rapid, lush foliage growth. Reduce to monthly in winter or stop if growth slows significantly. Treat that as every 2 weeks 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 painted nettle 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 painted nettle
Half strength is the safe default for painted nettle — 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 painted nettle first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the painted nettle watering schedule.
Signs you are over-feeding painted nettle
Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for painted nettle:
- 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 painted nettle
- 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 painted nettle care brief covers soil, humidity and the common problems for this species.
Flushing and leaching the salts
Flush the pot of painted nettle 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 painted nettle
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 painted nettle — frequently asked questions
What fertiliser does painted nettle 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. Painted Nettle 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 painted nettle?
Feed every 2 weeks during spring and summer with a balanced liquid fertiliser; a formulation with slightly elevated nitrogen supports rapid, lush foliage growth. Reduce to monthly in winter or stop if growth slows significantly. Feed every 2 weeks during spring and summer with a balanced liquid fertiliser; a formulation with slightly elevated nitrogen supports rapid, lush foliage growth. Reduce to monthly in winter or stop if growth slows significantly. Treat that as every 2 weeks 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 painted nettle?
Half strength is the safe default for painted nettle — houseplant feeds are formulated strong, and the diluted dose is gentler on the roots while still ample for foliage.
What does over-feeding painted nettle 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 painted nettle 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 painted nettle?
Flush the pot of painted nettle 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
- Painted Nettle care — the full brief (light, soil, humidity, problems, pet safety)
- How often to water painted nettle — 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 bird's nest anthurium
- How to fertilise hookeri anthurium
- How to fertilise anthurium plowmanii
- All 10153 fertilising guides in the Growli library