A Beginner's Guide to Caring for Calathea

Why Calathea Rewards a Little Patience

Calathea are the show-offs of the houseplant world, and deservedly so. Their leaves come painted with pinstripes, feathered edges and deep purple undersides, and many of them fold up at night as if in prayer — which is why they are often called prayer plants. What surprises new owners is that these plants are not difficult, just specific. They come from the floor of South American rainforests, where the light is filtered through a canopy, the air is muggy, and the soil rarely dries out completely. Copy those conditions in a British home and your Calathea will reward you for years.

Getting the Light Right

Think dappled shade rather than sunshine. An east- or north-facing windowsill is ideal, as is a spot a metre or two back from a brighter south- or west-facing window. Direct midday sun will scorch the leaves, leaving pale, papery patches that never recover, and even strong indirect light can fade the markings until your plant looks washed out.

If your only option is a bright, sunny room, a sheer curtain makes a real difference. Rotate the pot a quarter turn every week or so, too — Calathea lean towards the light, and a plant left in one position will soon develop a noticeable tilt.

Watering: Consistency Beats Generosity

Overwatering does more damage to Calathea than almost anything else, but so does letting them dry out completely. The goal is compost that stays lightly moist, like a wrung-out sponge, rather than sodden or bone dry. Check the top two to three centimetres with your finger before watering; if it feels damp, wait another day or two.

As a rough guide, most Calathea need watering roughly once a week in spring and summer, dropping to every ten to fourteen days in autumn and winter. Always empty the saucer or outer pot afterwards — standing water suffocates roots within a day or two.

Water quality matters here more than with most houseplants. Calathea are sensitive to the fluoride and chlorine in tap water, which shows up as brown, brittle leaf edges. Rainwater is the gold standard, filtered water works well, and leaving tap water to stand overnight in an open jug will let the chlorine dissipate. Water at room temperature, never straight from a cold tap.

Humidity Makes All the Difference

Central heating is the enemy of Calathea. These plants are happiest at around 50–60% humidity, while a typical heated British living room sits closer to 30–40% in winter. Low humidity is the single most common cause of crispy brown edges, so it is worth tackling properly.

• Stand the pot on a tray of pebbles with water kept just below the pebble line, so the roots never sit in it.
• Group several humidity-loving plants together — they create a microclimate as they transpire.
• A bathroom or kitchen with a decent window is often the best spot in the house, especially if someone showers daily.
• Keep plants well away from radiators, log burners and draughty doorways.

Misting is popular but overrated. It lifts humidity for minutes rather than hours, and water sitting on the leaves can encourage fungal spotting. If you enjoy doing it, mist in the morning so the leaves dry before evening.

Compost, Pots and Gentle Feeding

A free-draining, peat-free houseplant compost mixed with perlite or orchid bark — roughly three parts compost to one part grit or bark — suits Calathea far better than a dense, water-retentive mix. Choose a pot with drainage holes and resist the urge to go up more than one size at a time, as excess compost around the roots holds moisture and leads to rot.

Repot in spring every eighteen months to two years, or when roots appear at the drainage holes. Feeding should be modest: a diluted liquid houseplant feed every three to four weeks through spring and summer, at roughly half the strength recommended on the bottle. There is no need to feed at all between October and March, when growth naturally slows.

Reading the Leaves: What Your Plant Is Telling You

Calathea are unusually good communicators. A quick glance at the foliage will usually tell you what needs adjusting.

• Crispy brown edges: almost always dry air or tap water. Raise humidity and switch to rainwater or filtered water.
• Curling, rolled leaves: the plant is losing moisture faster than it can take it up — check for dry compost or too much direct light.
• Yellow lower leaves and a soggy compost surface: classic overwatering. Let the top few centimetres dry out and check the pot has free drainage.
• Faded or blurred patterns: too much light. Move the plant further from the window.
• Fine webbing and speckled leaves: spider mites, which thrive in dry air. Raise humidity, wipe both sides of every leaf with a damp cloth, and repeat weekly until the webbing stops returning.

Finally, don't panic when a leaf or two turns brown or yellow now and then. Cut it off at the base with clean scissors and carry on. With steady light, consistent watering and a bit more moisture in the air, a Calathea will keep producing those extraordinary leaves — and quietly become the calmest corner of the house.