Most gardeners will agree that growing a calathea can be a little bit challenging. Yes, they have exotic and eye-catching foliage worthy of display in your indoor space. But, they can also be fussy plants! They require specific watering, light levels, and fertilizer dosage to stay happy and pretty. This is why calatheas are often not the best plants for newbie growers.
Normally, calatheas close their leaves and point them upwards when the sun goes down, which is why they are nick-named prayer plants. During the day, their leaves will open up a bit and lay flat, which is also normal – as if they are capturing as much light as possible from their environment.
But – is it normal for calathea leaves to point down? Or does it mean trouble? Let us dig in to understand more about the behavior of this special herbaceous perennial.
Calathea plant overview
Calathea is a beautiful plant that is commonly used as interior decor, both in homes and in offices. Its wide, green leaves are boldly marked with unique stripes and veins, making them particularly eye-catching. When placed indoors, their stunning patterns can create a fresh and tropical vibe in the living space.
Calatheas are native to the tropical rainforests of South and Central America, the West Indies, and Africa. They belong to the Marantaceae family of plants – a family of flowering plants that includes stromanthe, ctenanthe, and maranta species. Overall, the Calathea genus has about 60 different species, so there is definitely a perfect cultivar to suit your taste and preferences.
Aside from their vibrant and beautiful foliage, calatheas are famously known as prayer plants, thanks to their nyctinastic behavior. This unique circadian rhythm allows their intricately-patterned leaves to lower and open up during the day, but when night time arrives, they begin to close and point upwards, like hands clasped in prayer. The purpose of this nyctinasty is not clearly understood by plant experts, but the unique movement is one of the many features that make calatheas special.
Calathea leaves’ nyctinasty
Gardeners are often amused at how the leaves of their calatheas move throughout the day, as if they have their own agenda. You may well be wondering what triggers these movements, and when to consider them normal.
Nyctinasty in plants is caused by an organ called the pulvinus at the base of the leaves. This tube-like structure has thin-walled plant tissue responsible for the absorption and release of water. Hence, with the help of this organ, the leaf base can swell or shrink, causing the leaves to move.
Moreover, the varying leaf orientations are also affected by the light intensity that the plant receives. As you might have noticed, calathea leaves are highly sensitive to different lighting levels, and not necessarily to the sunlight’s direction. Hence, their leaves make constant adjustments throughout the day, moving in an upward or downward direction.
The most prominent movements happen during the night. As soon as the sun sets, the leaves begin to change to a vertical position. This allows you to see the vibrant rosy colors underneath the foliage.
You might confuse the nyctinastic behavior of plants with phototropism. Keep in mind, however, that these phenomena are quite different! The phototropic reaction in plants is affected by the direction of sunlight, while nyctinasty is based on the light’s intensity.
Many experts believe that the closing of calatheas’ leaves at night is meant to reduce moisture loss via evaporation. Calatheas are not drought tolerant, so by conserving their water, they can increase their chances of survival.
While calathea leaves might normally lay flat and point in a downward direction during the day, it becomes an issue if they remain flat even at night time. If you notice your calathea leaves pointing down and not closing up after sunset, you might have a distressed plant on your hands. It might also begin to show other unhealthy signs, such as drooping or wilting, and the appearance of brown or brittle leaves.
Causes of calathea leaves pointing down
If you are quite sure that your calathea plant is in trouble due to its downward-pointing leaves, here is a list of common gardening mistakes that may have likely caused the sad appearance of your plant:
1. Lack of water
Calatheas do not like their roots to remain dry for very long. These plants need adequate moisture to stay happy, and if they are deprived of water, their signs of thirst will show on the leaves. The leaves will likely remain flat and appear droopy throughout the day – even when the sun goes down.
To revive a thirsty-looking calathea, simply provide it with adequate water. Check the soil with your finger before giving your plant a drink, remembering that the soil must be moist but not soggy. Never allow the soil to stay dry for long periods. Watering your plant once a week will usually suffice during normal weather conditions, but you can reduce or increase your watering depending on the dampness or dryness of the soil.
2. Inadequate lighting
Calathea leaves that look a bit limp and do not open up are likely light-deprived. In this case, their natural circadian rhythm has been altered since they are kept in areas that do not receive adequate light. Keep in mind that calatheas can still survive in low-light conditions, but we do not want our plants to barely survive – we want them to thrive and grow to their fullest potential.
If you think your houseplants are not receiving sufficient light to grow healthily, the solution is simply to move them to an area with bright, but not direct, sunlight. Keep in mind that calatheas also do not like strong sunlight, as the intense ultraviolet rays will likely burn their leaves.
A good daily dose of filtered light will usually allow these lovely perennials to grow optimally. If you do not have well-lit areas in your house, you can also opt for grow lights as an alternative.
3. Repotting stress
Calatheas can struggle with transplant stress, too! Like most other plants, they need ample time to acclimatize to their new pot. Thus, a newly-transplanted calathea that looks stressed with downward-pointing leaves is experiencing a temporary reaction and should not be cause for major concern.
What you need to do, though, is give the plant the best possible growing conditions to help it recover fast. Move it to a spot with moderate heat and lighting levels, and keep the soil moist but not overwatered, to prevent drowned roots. Once your plant is finally happy with its new home, it should bounce back to its normal, healthy state.
4. Overwatering
We all know that calatheas are moisture-loving plants – but too much water can be bad for them, too! Overwatering is a leading cause of plant death, and a fussy calathea plant will certainly not tolerate waterlogged soil.
Unfortunately, some symptoms of overwatering can be easily confused with underwatering. Aside from brown and brittle leaves, you might also notice the plant starting to droop and become lifeless. If your plant is not responding well despite reviving it with enough water, then it is probably overwatered.
In this case, we suggest checking the roots. If you notice signs of rotting, the roots may have been infected by fungal spores and this will have compromised your plant’s nutrient uptake.
Depending on the severity of root damage, an overwatered calathea can be challenging to save. If more than half of the roots are rotting, there is a good chance the plant will die no matter how hard you try to revive it. In this case, it is best to discard the infected plant and start again with a new one.
5. Drafts and low temperatures
Calatheas are sensitive to sudden temperature changes. Similar to transplant stress, inappropriate conditions can cause their leaves to curl and become limp.
Hence, your growing area should be free of drafts and away from heating or cooling vents. If your plants are placed near an open door or window, make sure to relocate them on cold or windy days. Ideally, their location should have a bright window and a stable temperature.
Calatheas also love a humid environment – ideally between 50 to 60 percent humidity. For most households, this humidity level might be difficult to achieve, in which case a humidifier will become your best friend to ensure your indoor climate is comfortable for both you and your plants.
When all the above growing conditions have been met, your calathea will thrive happily and without any issues.
Conclusion
Leaves that mimic human hands in prayer – this is one of the many unique features that make calathea plants so popular and special. When evening arrives, their leaves begin to close and point upwards, as if the plants are in sleep mode. As the sun starts to rise again in the morning, the leaves will slowly open up and relax, as if they are greeting the day with open arms.
But, when the leaves stay pointed down or show other unusual signs like drooping, it is time to investigate. Reassess your watering routine as well as the light levels in your growing area. Hopefully, you can determine the problem and save your plant from irreversible damage!
Image: istockphoto.com / Oleg Shuldiakov