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Fertilising guide

How to fertilise Philodendron Gigas (Philodendron gigas)— schedule & NPK

Also called Philodendron Gigas, Gigas, Velvet Giant Philodendron.

More about philodendron gigas

About Philodendron Gigas

Philodendron gigas · also called Philodendron Gigas, Gigas · tropical

Philodendron gigas is a rare climbing aroid from Panama, prized for huge, velvety, deep-green leaves with pale veins. Give it bright indirect light, a chunky aroid mix, high humidity, and a moss pole to climb. It is toxic to cats and dogs (calcium oxalates), so keep it well out of reach of curious pets.

Growth habit: A vigorous climbing hemiepiphyte: in the wild it scrambles up rainforest trees, and indoors it climbs a moss pole or trellis, putting out progressively larger velvety leaves as it gains height and develops aerial roots.

Watch for — Yellowing leaves: Usually overwatering or soggy mix; also possible with nutrient shortage or over-fertilizing. Check that the top inches dry between waterings and that the pot drains freely.

What fertiliser philodendron gigas actually wants — and why

Philodendron Gigas is a genuinely hungry tropical — in bright warmth it pushes growth fast and rewards a regular half-strength balanced feed all season.

A balanced liquid feed (even N-P-K) or a slightly nitrogen-leaning foliage feed — this is a big-leaved foliage plant putting on real size, so it wants steady nitrogen for lush leaves, not a bloom 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 philodendron gigas: 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 philodendron gigas, 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 philodendron gigas:

Feed with a balanced liquid houseplant fertilizer diluted to half strength every 2-4 weeks during spring and summer. Stop or greatly reduce feeding in autumn and winter when growth slows, to avoid a buildup of mineral salts that can scorch roots and yellow the leaves. For a fast grower like this that means feeding regularly — about every 2-4 weeks — right through spring through early autumn (roughly March to September), tapering off only as light drops in autumn.

The dormant-season rule matters more than the exact interval: skip feeding entirely when philodendron gigas 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 philodendron gigas

Half strength every feed is the sweet spot for philodendron gigas: frequent enough to fuel fast growth, dilute enough that it never scorches even when you feed often.

Feeding always goes onto already-damp soil, never dry roots — water philodendron gigas first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the philodendron gigas watering schedule.

Signs you are over-feeding philodendron gigas

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

Signs you are under-feeding philodendron gigas

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

Flushing and leaching the salts

Because you feed often, salts accumulate faster — flush the pot of philodendron gigas with plain water until it drains freely roughly every month through the feeding season to keep the root zone clean.

Organic vs synthetic feeds for philodendron gigas

Organic options

A diluted seaweed or fish-and-seaweed feed plus a yearly top-dress of worm castings supports fast growth without burn risk. UK: Westland seaweed or Baby Bio Organic; US: Neptune's Harvest or Espoma Indoor!.

Synthetic / liquid feeds

A balanced houseplant liquid at half strength applied frequently — UK: Baby Bio, Phostrogen or Westland Houseplant Feed; US: Miracle-Gro Indoor Plant Food or Dyna-Gro Foliage-Pro for steady leafy growth.

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 philodendron gigas — frequently asked questions

What fertiliser does philodendron gigas need?

A balanced liquid feed (even N-P-K) or a slightly nitrogen-leaning foliage feed — this is a big-leaved foliage plant putting on real size, so it wants steady nitrogen for lush leaves, not a bloom formula. Philodendron Gigas is a genuinely hungry tropical — in bright warmth it pushes growth fast and rewards a regular half-strength balanced feed all season.

How often should I feed philodendron gigas?

Feed with a balanced liquid houseplant fertilizer diluted to half strength every 2-4 weeks during spring and summer. Stop or greatly reduce feeding in autumn and winter when growth slows, to avoid a buildup of mineral salts that can scorch roots and yellow the leaves. Feed with a balanced liquid houseplant fertilizer diluted to half strength every 2-4 weeks during spring and summer. Stop or greatly reduce feeding in autumn and winter when growth slows, to avoid a buildup of mineral salts that can scorch roots and yellow the leaves. For a fast grower like this that means feeding regularly — about every 2-4 weeks — right through spring through early autumn (roughly March to September), tapering off only as light drops in autumn.

What strength of feed for philodendron gigas?

Half strength every feed is the sweet spot for philodendron gigas: frequent enough to fuel fast growth, dilute enough that it never scorches even when you feed often.

What does over-feeding philodendron gigas look like?

Brown, scorched leaf tips and margins despite correct watering. A white salt crust on the soil or around the pot edge. Sudden leaf yellowing and drop shortly after a strong feed. Soft, weak, over-stretched growth that cannot support itself. The mistake here is the opposite of most houseplants: under-feeding a fast tropical in peak season starves it, leaving small, pale new leaves and slow growth — but full-strength doses still burn it, so feed often and weak, not occasionally and strong.

Should I flush the soil of philodendron gigas?

Because you feed often, salts accumulate faster — flush the pot of philodendron gigas with plain water until it drains freely roughly every month through the feeding season to keep the root zone clean.

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