Growli

Plant care

Tree philodendron (split-leaf philodendron (large)) care

Thaumatophyllum bipinnatifidum

Also called lacy tree philodendron, split-leaf philodendron (large), horsehead philodendron.

RHS H1bUSDA 9-11Toxic to petsIndoor 1.5-2.5 m tall and wide indoors

Watering rhythm

7-10days

When the top 2-3 cm of soil is dry, every 7-10 days

Light

Bright indirect light (just back from a sunny window)

Soil

Rich aroid mix

Humidity

50-60%

Temp

18-27°C

Pet safety

Toxic to pets

Mature size

1.5-2.5 m tall and wide indoors

Care at a glance

Light

In the wild tree philodendron grows on the bright edge of a forest canopy, not in the canopy and not in the open. Indoors, that translates to within a metre of an unobstructed window, sheer curtain optional. Bright indirect light with some morning direct sun. The fastest test: a hand held at the leaf casts a soft-edged shadow at noon — sharp shadow means too much sun, no shadow means too little light.

Watering

Aim for when the top 2-3 cm of soil is dry, every 7-10 days for tree philodendron, but treat that as a starting point rather than a rule. A south-facing summer windowsill will dry the pot twice as fast as a north-facing winter room. Lift the pot; if it feels noticeably lighter than it did wet, water it. Likes consistent moisture but rots in soggy soil. Reduce in winter.

Soil and pot

Tree philodendron grows best in rich aroid mix. Compost with 20% perlite and orchid bark. A pot with a working drainage hole is non-negotiable for this species — even free-draining mix will turn soggy in a closed planter. If you love the look of a decorative pot without a hole, use it as a cachepot around an inner nursery pot you can lift out to water.

Humidity and temperature

Tree philodendron sits happiest at around 50-60% humidity and 18-27°C (65-80°F). Higher humidity produces larger leaves. If you keep the room above 18 year-round and avoid placing the plant near a cold draught, a hot radiator, or an air-conditioning vent, you have already handled the two biggest indoor stressors.

Fertilising

Feed tree philodendron sparingly. Balanced liquid feed at half strength monthly in growing season. Skip fertiliser entirely on a stressed, recently-repotted, or actively wilting plant — fertiliser salts make damage worse, not better. Wait for a round of healthy new growth before resuming a feeding rhythm.

Common problems

Below are the issues we see most often on tree philodendron in the Growli community. Each is annotated with the most common cause so you know where to start.

  • Yellow leavesOverwatering or root-bound — check before watering more.
  • Small new leavesInsufficient light or under-feeding.
  • Aerial roots everywhereNormal; can be tucked into the pot or trimmed.
  • Brown leaf tipsLow humidity or tap-water sensitivity.

Propagation

Stem cuttings from the growing tip or air layering for big specimens. Propagation is the cheapest, most satisfying way to expand a collection — and it doubles as insurance against losing a mature plant to an accident. Take a backup cutting once the parent is established and healthy.

Toxicity to pets

Tree philodendron is toxic to pets. ASPCA lists Philodendron and Thaumatophyllum species as toxic to cats and dogs due to insoluble calcium oxalates. If you keep cats, dogs, or curious children in the house, weigh placement carefully — a high shelf or a hanging planter is enough for casual safety. For severe ingestion incidents, call your local vet and the ASPCA Animal Poison Control Center (in the US, 888-426-4435).

Pet-safety status is sourced from the ASPCA Toxic and Non-Toxic Plant List, which catalogues the most-asked-about plants for cats, dogs, and horses.

Tree philodendron care — frequently asked questions

What is the common name for Thaumatophyllum bipinnatifidum?

Thaumatophyllum bipinnatifidum is most commonly called Tree philodendron, but it is also known as lacy tree philodendron, split-leaf philodendron (large), horsehead philodendron. The names refer to the same species, so care instructions for Tree philodendron apply identically to anything sold as split-leaf philodendron (large).

How much light does tree philodendron need?

Tree philodendron grows best in bright indirect light (just back from a sunny window). Bright indirect light with some morning direct sun.

How often should I water tree philodendron?

Water tree philodendron when the top 2-3 cm of soil is dry, every 7-10 days. Likes consistent moisture but rots in soggy soil. Reduce in winter. The finger-test (or lifting the pot to feel its weight) beats a fixed weekly calendar because pot size, light, and season all change how fast the soil dries.

Is tree philodendron toxic to cats and dogs?

Tree philodendron is toxic to pets. ASPCA lists Philodendron and Thaumatophyllum species as toxic to cats and dogs due to insoluble calcium oxalates.

What USDA hardiness zone does tree philodendron grow in?

Tree philodendron is rated for USDA zone 9-11 (indoor in most US homes) and RHS hardiness H1b. Outside that range, grow it as a container plant that overwinters indoors before the first hard frost.

Tree philodendron deep-dive guides

Every aspect of tree philodendron care, each with its own calibrated guide:

Featured in these plant shortlists

Tree philodendron qualifies for 3 curated Growli shortlists — each one filtered objectively from our structured plant-care library, so the selection is consistent and checkable:

Related guides

Tree philodendron is also known as lacy tree philodendron, split-leaf philodendron (large), and horsehead philodendron.