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Fertilising guide

How to fertilise Red Iochroma (Iochroma fuchsioides)— schedule & NPK

Also called Red Iochroma, Scarlet Iochroma, Fuchsia-flowered Iochroma.

More about red iochroma

About Red Iochroma

Iochroma fuchsioides · also called Red Iochroma, Scarlet Iochroma · tropical

Iochroma fuchsioides is a Colombian and Ecuadorian cloud-forest shrub bearing cascading clusters of narrow, brilliant scarlet to orange-red tubular flowers that attract hummingbirds. It blooms in waves through the warmer months, is fast-growing and responds well to pruning. A striking conservatory specimen where temperatures stay above 10°C. All parts contain alkaloids and are toxic.

Growth habit: Upright, somewhat open evergreen shrub

What fertiliser red iochroma actually wants — and why

Red Iochroma 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 red iochroma: 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 red iochroma, 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 red iochroma:

Feed every 2 weeks through spring and summer with a balanced liquid feed (NPK 5-5-5 or 10-10-10 at half strength). Switch to a potassium-rich feed in midsummer to support flowering. Withhold fertiliser from late October through February. 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 red iochroma 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 red iochroma

Half strength is the safe default for red iochroma — 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 red iochroma first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the red iochroma watering schedule.

Signs you are over-feeding red iochroma

Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for red iochroma:

Signs you are under-feeding red iochroma

If the symptoms point at watering, light or roots rather than nutrition, the full red iochroma care brief covers soil, humidity and the common problems for this species.

Flushing and leaching the salts

Flush the pot of red iochroma 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 red iochroma

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 red iochroma — frequently asked questions

What fertiliser does red iochroma 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. Red Iochroma 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 red iochroma?

Feed every 2 weeks through spring and summer with a balanced liquid feed (NPK 5-5-5 or 10-10-10 at half strength). Switch to a potassium-rich feed in midsummer to support flowering. Withhold fertiliser from late October through February. Feed every 2 weeks through spring and summer with a balanced liquid feed (NPK 5-5-5 or 10-10-10 at half strength). Switch to a potassium-rich feed in midsummer to support flowering. Withhold fertiliser from late October through February. 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 red iochroma?

Half strength is the safe default for red iochroma — houseplant feeds are formulated strong, and the diluted dose is gentler on the roots while still ample for foliage.

What does over-feeding red iochroma 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 red iochroma 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 red iochroma?

Flush the pot of red iochroma 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.

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