PlantRx

Philodendron leaves curling

By Karim DiabatePublished Updated How these guides are built

Curling is the earliest signal a philodendron gives, which makes it useful: it usually shows up before anything discolours. The direction of the curl and the feel of the leaf are what separate the causes.

A healthy Philodendron, photographed for reference
A healthy philodendron for comparison. This is a reference photo, not a picture of the problem. Photo by KENPEI (CC BY-SA 3.0), via Wikimedia Commons.

What is specific to this plant

  • Philodendrons signal light problems in the leaf size before the colour: each new leaf smaller than the last, on a plant with plenty of water, is a light problem.
  • Climbing types behave differently from self-heading ones. A vining philodendron given nothing to climb stays small-leaved indefinitely.

What it could be, and how to tell

These look alike in a photograph, so each one below lists what you would ALSO see if that is the cause. Work down the list and stop at the one where the other symptoms match too.

most common

1. Small leaves curling on a vine with nothing to climb

What else you would see

  • leaves staying small however long the plant grows
  • curling on those small leaves while the vine keeps extending
  • the vine trailing rather than climbing
  • no moss pole, stake or wall within reach
How to confirm it: Look at whether the plant is climbing or trailing. A vining philodendron sizes its leaves to what it is climbing, so one with nothing to grip stays small-leaved indefinitely, and small thin leaves curl at the slightest dryness where a large mature leaf would not. The curl is a consequence of the leaf size, and the leaf size is a consequence of the support.

What to do

  1. Give it a moss pole or stake and tie the vine in so the aerial roots can grip.
  2. Keep the pole damp, which is what triggers larger leaves.
  3. Expect the change on new growth only, since existing leaves stay as they are.
common

2. Underwatering or a hard dry-out

What else you would see

  • leaves curling under along the midrib before any colour changes
  • the far end of the vine light and papery while the crown still looks well
  • leaves that firm up again within a day of a thorough soak
How to confirm it: Dry soil pulled away from the pot wall, with foliage that improves noticeably within a day of a thorough soak. If a thorough watering changes nothing in twenty four hours, stop assuming thirst and check the roots.

What to do

  1. Water thoroughly until it runs freely from the drainage holes, rather than a splash at the surface.
  2. If the mix has gone water-repellent and the water runs straight through, stand the pot in a basin of water for half an hour to rewet it properly.
  3. Water on dryness rather than on a fixed day of the week, and this is how far it should dry: the top two inches.
common

3. Dry air

What else you would see

  • worse in winter once the heating is on
  • a radiator, a vent or a draught nearby
  • other plants in the same room showing crisp edges too
How to confirm it: Seasonal timing, and more than one plant in the room affected at once. That points at the room rather than at anything you did to this plant.

What to do

  1. Move it away from direct heat sources and draughts.
  2. Group plants together, or stand the pot on a tray of damp pebbles, so the air immediately around it is more humid.
less common

4. Too much light or heat

What else you would see

  • bleached, pale patches rather than an even colour change
  • damage only on the side or the leaves facing the window
  • leaves warm to the touch in the afternoon
How to confirm it: The pattern settles it: sun damage is one-sided and patchy, while watering problems and ordinary ageing are even across the plant.

What to do

  1. Move it back from the glass or filter the light. Philodendron wants bright indirect light.
  2. Bleached tissue does not turn green again. Judge recovery by whether NEW leaves come in a healthy colour.
less common

5. Spider mites

What else you would see

  • fine pale stippling or speckling across the leaf rather than solid patches
  • very fine webbing where the leaf meets the stem
  • a dusty look to the underside of the leaf, worst in warm dry air
How to confirm it: Hold a sheet of white paper under a leaf and tap it sharply. Specks the size of dust that then move are mites. The stippling is what separates this from any watering problem.

What to do

  1. Isolate the plant from your others straight away, before anything else.
  2. Rinse the leaves thoroughly, undersides included, with a strong spray of water, and repeat every few days. Mites breed faster than a single treatment can keep up with.
  3. Raise the humidity around the plant. Mites thrive in warm dry air and struggle in humid air.
  4. If you choose to use a treatment product, follow the label on it exactly. The label is the legal instruction and it overrides anything written here.
uncommon

6. Overwatering, and the root rot that follows

What else you would see

  • leaf stalks going soft and translucent within an inch of the stem
  • aerial roots along the vine browning and shrivelling rather than reaching
  • the mix still wet at the point where the vine leaves the pot
How to confirm it: Slide the plant out of its pot and look at the roots. Healthy ones are firm and pale. Brown, soft, or hollow when you press them means rot, and that changes what you do next completely.

What to do

  1. Stop watering and let it dry down this far: the top two inches.
  2. Check that the pot drains and empty any saucer or decorative outer pot it sits in. Water held out of sight keeps the mix wet whatever you change above it, and it stays invisible until you lift the pot.
  3. If the roots are soft and brown, trim them back to firm tissue with a blade sterilised first and repot into fresh chunky, free-draining aroid mix.

Common questions

Do curled philodendron leaves uncurl again?

If the cause is caught early, yes: leaves curled by thirst or heat often flatten out again once conditions steady. Leaves that have already crisped at the edge will not, and those are judged by the new growth instead.

Which way should the leaves curl?

Curling inward or downward usually points at water, heat or a root problem. Cupping upward more often points at light. Neither is a rule on its own, which is why the other symptoms in the list above matter.

Could it be pests?

Yes, and it is worth ruling out early. Turn a leaf over and look for fine stippling or webbing. Pest curling comes with speckling that no watering problem produces.

Is a philodendron poisonous to cats, dogs or children?

Philodendron contains calcium oxalate crystals and is widely listed as harmful to pets and children if chewed. We do not tell you that any plant is safe. If a pet or a child may have chewed any part of one, contact a vet, or Poison Control on 1-800-222-1222 in the US, immediately rather than waiting to see what happens.

Before you act on any of this

This is general plant care guidance for a plant, not advice about people or animals. We never tell you whether a plant is safe to eat or touch, and we never tell you a plant is safe for a child or a pet. If a child or animal may have eaten any part of a plant, contact Poison Control (US 1-800-222-1222) or a vet immediately rather than reading further.

Treatment advice here is deliberately category level. We do not give product names, mixing ratios or application intervals. Whatever the label on the product in your hand says is the instruction that counts, and following it is your responsibility.

Where this comes from

The general horticultural facts behind this differential come from published university extension and Royal Horticultural Society guidance. What is specific to this plant, and the order the causes are ranked in, is ours, and the methodology page says where that reasoning stops being reliable.

Other philodendron problems

Not sure which one it is?

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