Growli

Fertilising guide

How to fertilise Typhonium venosum (Typhonium venosum)— schedule & NPK

Also called Voodoo Lily, Devil's Tongue.

More about typhonium venosum

About Typhonium venosum

Typhonium venosum · also called Voodoo Lily, Devil's Tongue · tropical

Typhonium venosum (formerly Sauromatum venosum) is a tuberous aroid famous for a dramatic purple-spotted spathe that emits a strong carrion smell to attract fly pollinators. After flowering, a single umbrella-like, divided leaf unfurls on a mottled stalk. The dormant tuber will even bloom dry on a windowsill, making it a curiosity-grower favourite.

Growth habit: Tuberous, dormant-cycling aroid: a single foul-smelling spathe emerges first, then one large, deeply divided umbrella leaf on a spotted petiole. Dies back to a tuber each year and offsets readily.

Watch for — No flower: Small or immature tubers skip flowering; grow on for a season or two and feed the leaf well to build a tuber large enough to bloom.

What fertiliser typhonium venosum actually wants — and why

Typhonium venosum 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 typhonium venosum: 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 typhonium venosum, 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 typhonium venosum:

Feed every 2-4 weeks with a balanced liquid fertiliser only while the leaf is actively growing; do not feed the dormant tuber. Treat that as every 2-4 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 typhonium venosum 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 typhonium venosum

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

Signs you are over-feeding typhonium venosum

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

Signs you are under-feeding typhonium venosum

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

Flushing and leaching the salts

Flush the pot of typhonium venosum 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 typhonium venosum

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 typhonium venosum — frequently asked questions

What fertiliser does typhonium venosum 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. Typhonium venosum 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 typhonium venosum?

Feed every 2-4 weeks with a balanced liquid fertiliser only while the leaf is actively growing; do not feed the dormant tuber. Feed every 2-4 weeks with a balanced liquid fertiliser only while the leaf is actively growing; do not feed the dormant tuber. Treat that as every 2-4 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 typhonium venosum?

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

What does over-feeding typhonium venosum 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 typhonium venosum 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 typhonium venosum?

Flush the pot of typhonium venosum 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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