Calathea medallion is one of the most popular indoor low light plants. Read our comprehensive care guide for this plant during the different seasons of growth.

Plant Description + Benefits

Growing calathea medallion indoors is beneficial and goes without saying. Apart from brightening and livening up your gloomy indoor space, they help in purifying the air. Moreover, they are not harmful (non-toxic) to humans.

Native to tropical rainforests in South America, Calathea Medallion grows 2 -3 feet. It grows upright and bushy.

While top surfaces of the leaves have eye-catching natural patterns, the undersides are tinted purple. New leaves grow and emerge tightly rolled from rhizomes. These leaves fold up slightly in the dark. The plant is propagated by the division of rhizomes. Calathea medallions are sensitive too.

1) Where to Place Calathea Medallion

Good caring for your Calathea Medallion begins with where it will be situated. The plant loves being treated with low-medium indirect light. For it to grow and be happy it detests being moved often.

Places to avoid:

• Direct sunlit open windows in the south and west during the summer
• Locations where they could be disturbed or touched over
• Open windows and doors or inlets for cold drafts
• Heat vents or ventilators

Where will they benefit the most and be happy?

• South and Northern facing windows with shields
• Bathroom surrounding or areas

2) How to Keep Up Temperature & Humidity

Calathea Medallions prefer to be treated with warm and humid conditions. 65 – 75 degrees F is the optimal comfortable temperature range. Maintain humidity level above 50 % but below 68%.

Besides a good watering habit, here are a few things to do.

• Provide ample humidity in the winter by running a humidifier. Alternatively, place your potted plants on top of a saucer filled with water pebbles
• Mist-spray your calathea medallion at least once a week more so in the summer
• Try placing one or two of your houseplants on top of the bathroom or kitchen chest-high tops. Monitor their growth closely

You will find the use of monitoring tools more useful. So work closely with thermometers and moisture meters or hygrometers if possible.

3) How to Water + Frequency

All Calathea Medallions should be watered regularly but accordingly. They need moist soils to stay happy and keep performing at their best. Before resorting to any watering routine, you need to be checking the soil dryness from time to time.

Dip your finger a few inches (about 2 or so) deep to feel. If you are note sure, use a water sensor. Alternatively, keep humidity levels (40 – 60) percent.

Frequency in watering means how many times (rate) say, per day or week. Therefore, frequency coupled with amount and quality of water are key factors to the quality watering of your houseplants. Also, various things change with each growing season. For example, it is a bit dry in the summer as compared to the winter months. This means the individual plants may need to be watered differently.

During the summer, water twice weekly. In the winter, reduce the watering frequency to once per week. Warmth and humidity play a determining role. When you water them avoid soaking or flooding the pot.

4) Repotting: How-to Steps & Tips

As houseplants, calathea medallion needs to benefit from repotting. Repotting in essence is like giving them a new start.

TOP TIP: Before starting to re-pot, you should have your mixture and pots ready.

To repot best follow these simple steps:

• To remove your calathea from the current pot, turn it over to the side.
• Tap the bottom lightly to loosen the soils attached to the walls of the pot.
• While still turned over, hold the pot and then gently slide your calathea out
• Use your hands to loosen the soil around the roots. Alternatively, wash the roots to clear the soil
• Carefully examine the roots for any signs of stress or rot. Smell them too.
• Add your fresh porous potting mixture to the new pots

TOP TIP: Do not compress or apply pressure around your newly potted mixture

• Place the plant in the new pot maintaining the soil level to the plant
• Remove the old stems and leaves by using sharp cleaned tools

If you ignore to re-pot them, they outgrow their current pots. The roots become stunted and the plant comes to standstill.

Key Repotting Guide Tips

Repotting at the beginning of a growing season (preferably in the spring) means your houseplants will likely benefit a lot more.

To make this more practical and find what works better, try it out yourself. You can grow or have a good number of these types of calathea. Have a few re-potted at the beginning of the growing season. Then get a few more houseplants re-potted say in the mid-end of the growing season.

• Don’t wait until your plant roots start growing and emerging from drainage holes. Sometimes you will realize roots emerging up and out of the soil surface.
• Use a 1.8 – 2.5 inch wide pot.
• Porous pots (terracotta) or containers are the best choices since they help in water evaporation.
• Avoid repotting small plants in large pots as they can easily be overwatered

5) Fertilizer + Feeding

Fertilize regularly through spring and the summer. We recommend water-soluble fertilizers. Dilute your select-best fertilizer with rain water to avoid applying it in excess. (Don’t over-fertilize!)

Reduce the frequency of feeding when fall arrives. Stop feeding your calathea as winter enters until the end. For fall feeding, you can apply an all-purpose foliage feeder.

These feeders should have quality preservation for nutrition – since you won’t fertilize/feed your houseplant in winter.

6) Remove Lower Yellow, Brown Outer Leaves

Yellowing in leaves can be a sign of the lower leaves aging. It is easy to identify this natural yellowing pattern. During the daytime, simply examine the whole leaves to see and ensure all younger ones are turgid.

Cut the yellowed leaf at its stalk joint with a clean and sterilized sharp knife or pair of scissors. Remove dry stalks and older lower leaves.

7) Clean the Leaves

Wash the leaves with a cool and damp soft-cotton material. This will discourage the build-up of pests and dust to ensure stomata are always open.

8) Specific Calathea Medallion Problems

Below are problematic issues – including pests and diseases – that this houseplant is prone to. Read on and find how to address them as ways to care for your calathea medallion.

a) Spider Mite Infestation

These plants are prone to spider mites. Keep an eye on the webs and red rusty spots on your plants. Though difficult to notice, you can also see them moving (creepy motions). Then treat them immediately.

Soak soft-cotton rolls and gently wipe leaves with rubbing plant alcohol. Dish soap solution does work to prevent them from taking over your plant. Let these products stay on the plant for 2 hours. Then you may wipe leaves with excess parts.

TIP: Works perfectly well when spider mites haves not completed a life cycle + if their number is still small.

Note that washing alone cannot remove laid eggs if your plants are left infested.

b) Fungus Gnats

Calathea Medallion requires moist soils much of the time. Unfortunately, this is when the fungus gnats will very likely come around. This does not mean you stop watering properly. You may reduce watering but do not let pots dry out.

This is what you are supposed to do:

• Check in the pots or leaves for signs of eggs or the gnat larvae
• Lay yellow sticky traps or vinegar traps near the plant locations to help control the adult population moving into the house
• Purchase indoor spray products for control of fungus gnat larvae
• Place potatoes in the pots to fight its pop
• Prepare household apple cider vinegar using the formula 1-half glass:1 part of water

To prevent them, purchase soil mixes from reputable sellers only. Shield the widows in which your houseplants live with traps.

c) Leaves Curling

When you notice the plant leaves are curling during the day act quickly. This is a sign your plant is experiencing stress. Either water in the pot or the air humidity level has dropped.

Pests such as spider mites can make the leaves curl. Look around the plant. Under the leaves and on the stems to check for pests.

d)Leaves Browning/Spotted

If you see brown leaf tips, first check humidity levels. Small sections of leaf edges turning brown can be caused by impurities (if you water your plants using tap water). And brown spots are usually a sign of pest.

Brown spots on leaves are also a sign of concentrated salts from fertilizers. Try flushing if you have corrected the other problems. Set your symptomatic calathea medallion pot under a rainwater tap and flush it. Drain the pot and stop applying fertilizer/feeder.

e) Fading Leaves

Fading leaves is a sign the exposed leaves are silently suffering from scorching effects (even if it’s indirect light). Move your calathea further off current lighting conditions.

Summary – Main Key Care Tips

Caring for your calathea medallion indoors is not difficult. However, if you love them you need to show them complete care. Watering, temperature, moisturizing, repotting, lighting and fertilizing are the main care areas. Disease and pest control are the other measures that need effort.

Conditions indoors are not similar to those in a greenhouse. With the help of devices, (e.g. moisture meter) you can adjust and maintain moisture for your calathea medallion to enjoy. Like all the other calathea plants, you should do light pruning only when necessary.

References & Sources

Calathea. ASPCA PET HEALTH INSURANCE. https://www.aspca.org/pet-care/animal-poison-control/toxic-and-non-toxic-plants/calathea. Accessed online 21 Oct 2021