Calathea Grey Star (Ctenanthe Setosa ‘Grey Star’): Ultimate Care Guide

With a silvery tone on the top of its leaves and violet-red underside, Calathea Grey Star is a plant to behold. The long arrow-shaped leaves are accented with narrow stripes of darker green enhancing and drawing attention to the beautiful greenish-grey canvas displaying them.  The stems are long and graceful, holding the leaves at the top in a way that exhibits each leaf reverently.

These gems in your plant collection originate in the rainforests of Brazil.  They are a clump forming plant and grow low to the ground. Calathea Grey Star belongs to the Marantaceae or prayer plant family.  Their leaves spread open in the daytime to absorb all of the light they can through the treetop canopy of the rainforest and fold up at night, resembling praying hands to conserve energy in the dark.

The botanical name for Calathea Grey Star is Ctenanthe Setosa and its more common names are prayer plant and never never plant.

What are the benefits of keeping a Calathea Grey Star?

Plants are a great way to increase oxygen in a space because they exchange our carbon dioxide for more oxygen.  Calathea Grey Star is also an air purifier, it filters pollutants out of the air to give us cleaner breathing. They make great bedroom plants for this very reason, allowing us to breathe fresher air throughout the night to wake up reinvigorated.  Occasionally wiping down Calathea Grey Star with a damp cloth to remove any dust allows it to filter more efficiently.

Calathea Grey Star Care

Calathea Grey Star is not any more difficult to care for than any other prayer plant.  They need the right amount of humidity, they like to be kept warm and away from drafts and they require a goldilocks amount of sunlight.  Not too much and not too little, just right.

Calathea Grey Star
Calathea Grey Star

How to care for Calathea Grey Star as an indoor plant

Place your Calathea Grey Star near an East or North facing window.  If neither of those directions is a possibility use a sheer curtain to filter the light so it’s not too harsh for your Calathea Grey Star. Keep your plant away from drafty doors and windows as well as heating and cooling vents.

How to care for Calathea Gray Star as an outdoor plant

If you live in a hot and humid climate you have the option of planting your Calathea Grey Star outdoors to enhance your landscaping.  It should be planted in the shade to receive filtered light through other plants near it to emulate its natural habitat.

Lighting Requirement

Bright indirect sunlight is necessary for Calathea Grey Star.  Too much or too little sunlight will cause its delightful color variegation to fade.  Not enough light will also cause Calathea Grey Star to get spindly and not grow in the pleasing full fashion we all want to have.

Soil Type and pH Requirement

Well-draining soil that retains moisture and stays light and airy is best for Calathea Grey Star.  A mixture intended for African violets is an excellent simple solution.  Another option is to mix equal parts peat, perlite, and potting soil for your Calathea Grey Star to thrive in.

The optimum pH for Calathea Grey star is slightly acidic to neutral, 6.1 to 7.3.

Watering Requirement

Calathea Grey Star likes to have consistently moist soil, but not soggy wet soil. Water your Calathea Grey Star when the top inch of soil is dry.  Let the water drain out the containers drain holes at the bottom and discard any water left in the tray to ensure your Calathea Grey Star will not be sitting in water. Do not allow your Calathea Grey Star to dry out completely.

Calathea Grey Star is also sensitive to minerals commonly found in tap water such as chlorine and fluoride. To avoid poisoning your plant with these substances, there are a few options. You can use rainwater or distilled water to water your plant, or you can let your tap water sit on the counter for at least 12 hours to let the minerals dissipate out of the water and then pour it into your Calathea Grey Star.

Calathea Grey Star Plant
Calathea Grey Star plant in a pot

Humidity Requirement

Humidity is one of the important care aspects of  Calathea Grey Star.  There are several ways to ensure your plant is humid enough. The simplest way is to mist your Calathea Grey Star every 1-2 days. You can also place it in a bathroom window where it will benefit from the shower steam.  A tray of pebbles and water underneath your Calathea Grey Star will add moisture to the air around it (be sure your plant is not sitting directly in the water). Add a small humidifier to the room your Calathea Grey Star is in to allow it to thrive in the humidity it needs.


Calathea Grey Star doesn’t like temperature fluctuations and they prefer to be kept warm.  A steady temperature between 60F and 77F will keep your Calathea Grey Star happy.

Calathea Grey Star Hardiness Zone

Especially if you are planting your Calathea Grey Star outside, you will need to pay attention to the hardiness zone in your area.  The best hardiness zone for Calathea Grey Star is 10-11 USDA


Use a highly diluted general houseplant fertilizer in the spring and summer when your Calathea Grey Star is in its growing season. Fertilization can be paused in the fall and winter as your Calathea Grey Star will not be growing nearly as much. Be careful not to over-fertilize your plant.


Propagating a cutting of Calathea Grey Star in water is not an option. These plants are propagated through division. In early spring when your Calathea Grey Star is ready to be repotted, it is the perfect time to also propagate it. Have a sterilized razor blade or sheers on hand. Carefully uproot your Calathea Grey Star from its container and gently shake the soil from the roots. Separate the roots and at least three coordinating stems from the parent plant and carefully cut them to have a completely independent second plant.

Put each plant into its own new container with fresh, clean soil.  Keep them a little more shaded and be sure to watch them for signs of shock for a week or two.  Once they are growing well care for them as usual.

Calathea Grey Star Size and Growth Rate

Calathea Grey Star’s mature size is three feet tall and three feet wide.  They can grow quite quickly and should be repotted about once a year.

Common Problems with Calathea Grey Star

The most common pests to bother Calathea Grey Star are red spider mites and mealybugs.  Red spider mites invade when the soil is too dry.  The signs that spider mites are present are small webs on the plant and tiny yellow bumps on the underside of the leaves.  Mealybugs present as cottony areas in the crevices of leaves and stems.

Both insects can usually be remedied by giving your plant a shower to remove the bugs and then treating the Calathea Grey Star with neem oil or insecticidal soap.

Leaves curling

If your Calathea Grey Star has curling leaves it means it is dehydrated and is trying to conserve moisture. Eventually, the leaves will end up falling off if not treated. Give your Calathea Grey Star a nice drink of water allowing excess to drain out of the bottom of it and monitor it to make sure the soil stays moist but not soaked.

Leaves turning yellow

Yellow leaves mean that your Calathea Grey Star is getting too much sunlight.  Try moving it further from the window or using a sheer curtain to filter the light.

Leaves with brown edges

Brown edges on your Calathea Grey Star’s leaves mean the humidity is too low.  Try using a small humidifier, grouping plants with similar humidity needs together so they can supply each other with humidity resources, or move your Calathea Grey Star to the bathroom to take advantage of some shower steam.

Drooping leaves

If your Calathea Grey Star is overwatered its leaves will start to droop. To remedy this situation make sure the drain holes aren’t clogged.  If the soil is too waterlogged, try repotting the plant in dry soil in a different container.

Plant Dying

The most common reason for Calathea Grey Star to die is root rot.  The cause of root rot is overwatering. If you find your Calathea Grey Star is dying, try uprooting it, cutting away the rotten roots with sterilized sheers, and repot it in clean dry soil.

How to repot Calathea Grey Star

Calathea Grey Star should be repotted once a year in early spring.  This is to make sure the soil remains light and airy, soil nutrients are replenished and your Calathea Grey Star has room to grow.

Start by uprooting your Calathea Grey Star and gently shaking the soil from the roots. Fill a new larger container 1/3 full of clean fresh soil mix. Place the roots of your Calathea Grey Star on top of the soil and fill the rest of the pot with soil around your Calathea Grey Star. Pat the soil gently.

Do Calathea Grey Star flower? 

Calathea Grey Star does flower.  The blossoms are white or yellow and quite underwhelming.  The real spectacularness of the plant is the foliage.

Does Calathea Grey Star move at night?

Calathea Grey Star is a member of the prayer plant family and the leave fold up at night resembling praying hands and unfold in the morning to absorb sunlight.

Is Calathea Grey Star safe for pets?

Calathea Grey Star is nontoxic for both cats and dogs.

Where can I find Calathea Grey Star for sale?

Calathea Grey Star can be purchased online and in some specialty brick and mortar plant stores. The prices vary from USD 18 to USD 61.

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