Calathea orbifolia

Identification and origin

Goeppertia orbifolia belongs to the family Marantaceae, the family of the prayer plant (Maranta leuconeura). It is native to the tropical rainforests of eastern Brazil, in the northeast and southeast of the country. Long placed in the genus Calathea, it has been moved to Goeppertia, but it is still sold as Calathea orbifolia. Its epithet comes from the Latin orbis, “circle,” and folium, “leaf.”

It is an evergreen herbaceous perennial that forms a dense, upright, compact clump from rhizomes. In a container it reaches 2–3 ft tall and 12 in – 2 ft wide, and takes two to five years to reach mature size. Its nearly round, slightly wavy leaves can be up to 12 in wide. They are glossy dark green, marked with broad silvery-green bands running out from the midrib; the undersides are pale green to silver. The small white flowers, borne in clusters, appear only under ideal conditions and almost never indoors.

Like many calatheas, its leaves move during the day: in the evening they fold upward like hands in prayer, then open again in the morning. This movement is called nyctinasty. The plant grows fairly fast and is long-lived when its needs are met. Its size makes it a handsome tabletop or floor plant.

Light

Give it bright but indirect, filtered light, or part shade. In summer a spot near a north- or east-facing window works well; in winter, when light levels drop, a south-facing window is better, as long as the sun does not fall directly on the leaves. A grow light can make up for a dim room.

Watch the foliage: direct sun scorches the leaves, while too little light makes the stripes fade and growth turn weak and poor, a common problem with Goeppertia.

Watering

The potting mix should stay moist at all times without ever becoming soggy. In spring and summer, water moderately but regularly to keep the root ball evenly moist. In fall and winter, let the surface dry before watering again, but never let the root ball dry out completely. Always empty the saucer or cover pot: roots that sit in water rot quickly.

Use rainwater or distilled water when you can. Fluoride in tap water browns the leaf tips; if tap water is all you have, let it stand for twenty-four hours before use so the chlorine evaporates. Water at the base without wetting the foliage, which encourages leaf spots.

Air humidity matters as much as watering: aim for at least 60 percent. A bright bathroom or kitchen suits it well. Elsewhere, run a humidifier, set the pot on a tray of gravel or clay pebbles kept moist, with the bottom of the pot above the water, or group it with other plants. Wipe the leaves regularly with a damp cloth: dust interferes with photosynthesis.

Potting mix

Choose a peat-free houseplant mix that drains freely yet holds moisture, slightly acidic to neutral. A multipurpose mix with about 10 percent fine grit by volume also works. The pot must have drainage holes.

During the growing season, from spring to fall, feed once a month with a balanced liquid houseplant fertilizer. Do not feed in fall or winter.

Temperature

It needs gentle and above all steady warmth: 64–75 °F suits it well. Do not let it drop below 61 °F. Avoid sudden swings: keep it away from cold air currents, open windows in winter, radiators and other heaters. Outdoors in the ground it grows only in tropical climates, USDA zones 11a to 12b.

It is sensitive to cold from the moment you buy it: if you purchase one during the cold season, wrap it well for the trip home.

Repotting

A newly purchased plant can stay in its pot for its first growing season. After that, repot it every few years, in spring or summer, once the clump has filled the pot. Choose a container just slightly larger, one or two sizes up. Set the root ball so its top sits just below the surface of the mix.

If you mix a slow-release fertilizer into the potting mix when repotting, there is no need for liquid feeding during the first year.

Pruning

No pruning is needed. Simply cut off browned or dried leaves and dead stems at the surface of the mix to keep the clump tidy.

Propagation

The recommended method is dividing the clump, in spring or summer, when you repot. Unpot the plant and cut the root ball into several sections, each with several leaves and a piece of rhizome with roots. Pot them up separately in fresh mix, then keep them warm, in humid air and constantly moist mix, until growth resumes.

Common problems

• Brown leaf edges and tips: dry air, or fluoride in tap water.
• Curling leaves: lack of water or dry air.
• Fading stripes, weak growth: too little light.
• Scorched, bleached patches: direct sun.
• Spots on the leaves: foliage wetted when watering.
• Patchy, water-soaked areas, mainly in winter: edema, when the mix stays too wet and the plant cannot transpire properly.
• Root rot: overwatering.
• Pests: spider mites (speckled or silvery leaves, fine webbing), mealybugs and scale, which leave black sooty mold, aphids and whiteflies. Fungus gnats signal a mix that is too wet: water from the bottom and water less often.

A single symptom can have several causes: look at light, watering, temperature and humidity together before making changes.

Toxicity

No toxicity is reported for dogs, cats or horses: calatheas are classed as non-toxic to animals. It is therefore a good choice for homes with pets; if an animal shows unusual symptoms after eating it, still consult a veterinarian.