Anthurium Leaves Curling: Water, Dry Air, Cold or Thrips?

A healthy anthurium leaf is flat, glossy and heart-shaped. NC State Extension describes Anthurium andraeanum leaves as large and glossy, up to 30 cm (12 in) long. When the edges roll in or the blade cups, the plant is losing water faster than its roots can replace it.

That points to a short list of causes. Start with the mix, because it rules out the most common one in a minute.

Sort the cause

What you find	Likely cause
Mix dry well below the surface, pot light, leaves limp and curling	Underwatering
Mix wet, older leaves yellowing, roots brown and soft	Root damage from too much water
Curling with brown edges, plant near a radiator or in centrally heated air	Dry air
Curling after a cold night, a draughty window or a car journey in winter	Cold injury
Brown tips and margins, white crust on the mix, heavy feeding	Salt build-up
Twisted, distorted new leaves with pale flecks	Thrips
Fine pale speckling and webbing under the leaves	Spider mites

Underwatering. Clemson Extension’s houseplant disorders factsheet says chronic underwatering leads to wilting and leaf curling. Virginia Cooperative Extension’s watering guide lists leaves that curl upward or downward, a light pot and mix shrinking from the pot edge as signs.

Too much water. Wet roots can’t take up water either. The RHS anthurium guide says overwatering or waterlogged compost causes root rot. Clemson adds that overwatering cuts the oxygen roots need and favours root diseases.

Dry air. NC State says anthuriums like humidity of 60 to 80 percent. Its genus page notes that leaf tips turn brown when humidity is too low. UF/IFAS’s anthurium fact sheet warns that below 50 percent relative humidity, leaves lose their shine and may die off. The RHS links brown leaf edges to the dry air of centrally heated homes.

Cold and draughts. NC State says the plant doesn’t tolerate cold draughts or sudden temperature changes. UF/IFAS’s interiorscape anthurium guidelines advise keeping air above 13 °C (55 °F), or visible or hidden damage may follow. They also warn about heat or cold from appliances such as televisions and refrigerators.

Salts. The same UF/IFAS guidelines say overfeeding indoors builds up soluble salts that injure leaf margins and tips.

Pests. NC State lists thrips, spider mites, mealybugs, scale, aphids and whiteflies for the genus. UC IPM’s thrips pest note describes distorted, curled shoot tips and leaves with tiny pale spots.

What to do

1. Test the mix. The RHS suggests checking about 5 cm (2 in) below the surface. Water only when it is nearly dry at that depth.
2. If it is dry, water thoroughly, as UF/IFAS advises. For a very dry root ball, Virginia Cooperative Extension suggests bottom watering for 15 to 30 minutes.
3. If it is wet, stop watering and unpot the plant. Soft, brown roots need the steps in our anthurium overwatering guide.
4. Move it. Keep it at 18–30 °C (65–86 °F), as the RHS advises, away from radiators, air vents and cold glass.
5. Raise the humidity. UF/IFAS suggests trays of moist gravel. The RHS also suggests grouping plants or a bathroom.
6. Flush salts if you see white crust. Pour plain water through the pot and let it drain fully.
7. Check for pests. Shake new growth over white paper, as UC IPM suggests for thrips. Use a hand lens under the leaves for mites.

Use rainwater or filtered water at room temperature, as the RHS recommends. A curled leaf may not flatten again, so judge recovery by the next leaves.

Keep it from coming back

Water by feel, not by date. Our anthurium watering guide covers timing through the year. Keep the plant in bright, indirect light; NC State warns direct sun can scorch the leaves. Feed lightly, since UF/IFAS links salt damage to overfeeding.

If you find webbing, follow our anthurium spider mite guide. For thrips on any houseplant, see thrips on houseplants. Spots rather than curls are covered in our anthurium brown spots guide. The anthurium problems sorter lists other symptoms, and why houseplant leaves curl, crisp or wrinkle compares leaf shapes across plants.

Wear gloves when you repot. NC State notes the sap can irritate skin and eyes.

References

• RHS: How to grow anthuriums
• NC State Extension Gardener Plant Toolbox: Anthurium andraeanum
• NC State Extension Gardener Plant Toolbox: Anthurium
• UF/IFAS Extension: Cultural Guidelines for Commercial Production of Interiorscape Anthurium (EP159)
• UF/IFAS Extension: Anthurium spp., Tailflower, Flamingo Flower (FP042)
• Clemson Cooperative Extension, HGIC 2251: Houseplant Diseases & Disorders
• Virginia Cooperative Extension: Properly Watering Container Houseplants (SPES-804)
• UC IPM: Pest Notes: Thrips (Publication 7429)