Calathea Undulata (wavy calathea) care

Light

Calathea Undulata wants the spot a few feet back from a sunny window — bright enough to read a paperback at noon, but the sun never falls directly on the leaves. Bright filtered to medium indirect light preserves the silvery feather and purple underside. Direct sun scorches and bleaches the small leaves; deep shade flattens the contrast. A faint hand shadow at midday is the right amount; a sharp dark shadow means it's getting direct sun and probably too much.

Watering

Water calathea undulata when the top 2 cm of soil starts to dry, roughly every 5-7 days in growth. The actual day count varies with pot size, light, and season — the finger test (or lifting the pot to feel its weight) is more reliable than a fixed calendar. Empty any drainage saucer afterwards so the pot isn't sitting in water. Keep the mix evenly moist; this is one of the thirstier, more humidity-dependent calatheas. Use rainwater, distilled or filtered water to avoid tip browning from fluoride and salts. Reduce in winter but never let it dry out.

Soil and pot

Calathea Undulata grows best in light, moisture-retentive, well-aerated mix. A peat-free coir blend with fine bark and perlite holds moisture while draining freely. Slightly acidic (pH 6.0-6.5). A pot with drainage holes is essential. 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

Calathea Undulata sits happiest at around 60-75% humidity and 18-27°C (65-80°F). Very high humidity is needed; this species crisps quickly below ~55% and thrives in a terrarium or grouped, humid setting. Use a humidifier or pebble tray and keep away from draughts. 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 calathea undulata sparingly. Feed every 3-4 weeks in spring and summer with a balanced houseplant fertiliser at half strength. Flush the soil periodically to clear salts, and stop feeding in autumn and winter. 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 calathea undulata in the Growli community. Each is annotated with the most common cause so you know where to start.

• Crispy leaf edges and tips — Low humidity or hard/fluoridated tap water; raise humidity well and use filtered, distilled or rainwater.
• Curling leaves — Underwatering or dry air; this thirsty species needs consistently moist soil and high humidity.
• Yellowing leaves — Overwatering or soggy soil; ensure drainage and let only the surface dry between waterings.
• Faded feather pattern — Too much direct sun bleaches the markings; move to bright indirect light.

Propagation

Propagate by division in spring at repotting: separate the rootball into sections each with roots and several leaves, pot up, and keep warm and very humid until established. It is not grown from cuttings. 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

Calathea Undulata is pet-safe. ASPCA-listed as non-toxic to cats and dogs. As a Calathea/Goeppertia prayer plant it lacks the insoluble calcium oxalates of toxic aroids and is safe around pets; nibbling may still cause minor stomach upset. 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.

Calathea Undulata deep-dive guides

Every aspect of calathea undulata care, each with its own calibrated guide:

• Calathea Undulata watering schedule
• Calathea Undulata light requirements
• Best soil mix for calathea undulata
• Calathea Undulata fertilizing guide
• When to repot calathea undulata
• How to propagate calathea undulata
• Calathea Undulata growth rate & size
• Calathea Undulata cold hardiness
• Calathea Undulata temperature & humidity
• Is calathea undulata toxic to cats & dogs?
• Is calathea undulata toxic to cats?
• Is calathea undulata toxic to dogs?

Featured in these plant shortlists

Calathea Undulata qualifies for 12 curated Growli shortlists — each one filtered objectively from our structured plant-care library, so the selection is consistent and checkable:

• Best pet-safe houseplants — Houseplants the ASPCA lists as non-toxic to cats and dogs — every one verified against the ASPCA toxic and non-toxic plant list.
• Best low-light houseplants — Houseplants that need no direct sun and cope with a north-facing room or a spot well back from a window.
• Best plants for a north-facing window — Houseplants for a north-facing window: bright, even, indirect light and no scorching direct sun. Each pick verified against its documented light needs.
• Best pet-safe low-light plants — Non-toxic to cats and dogs AND happy with no direct sun — the two hardest constraints to satisfy at once.
• Best humidity-loving houseplants — Houseplants that thrive in a bathroom, kitchen, or by a humidifier — selected by documented humidity preference.
• Best bathroom plants — Humidity-loving houseplants that also cope with lower light — suited to the steamy, often-dim conditions of a typical bathroom.
• Best pet-safe bathroom plants — Non-toxic to cats and dogs and happy in the humid, lower-light conditions of a bathroom — safe greenery for the smallest room.
• Best small & tabletop houseplants — Compact houseplants that stay under about 40 cm — desk, shelf and windowsill plants that never outgrow a small space.
• Best pet-safe bedroom plants — Non-toxic to cats and dogs and happy in lower light — calming greenery for a bedroom where a pet often sleeps too.
• Best cat-safe plants — Houseplants the ASPCA lists as non-toxic to cats (and dogs) — safe greenery for a home with a curious cat.
• Best dog-safe plants — Houseplants the ASPCA lists as non-toxic to dogs (and cats) — safe greenery for a home with a curious dog.
• Best small pet-safe plants — Compact, tabletop houseplants that are also ASPCA non-toxic to cats and dogs — safe greenery for a desk or shelf.
• Browse all 29 plant shortlists — pet-safe, low-light, drought-tolerant and more

Related guides

Calathea Undulata is also commonly called wavy calathea or undulate calathea.

• Types of calathea — varieties identified, with care and pet-safety
• Snake plant care — light, water and common problems
• Dracaena care — light, water and common problems
• Peperomia care — light, water and common problems
• All 2464 plant care guides in the Growli library