Calatheas or “prayer plants” are incredibly popular within the houseplant community because of their fun patterns and colors, they can become a statement plant within in any home! A question that a lot of growers ask though is “why do their leaves move?”. If you look at your calathea from day to night they will look completely different! This is because their leaves will often point vertically at night time, pretty cool hey! But why does this happen?
Calathea leaves move in response to changing light through nyctinastic movement. They do this because at night time the leaves aren’t collecting light, by making the leaves sit vertically it allows water to run off and reduces the possibility of fungus or bacteria growing on the plant.
How do calathea leaves move?
Nyctinastic movement or nyctinasty is what causes calathea leaves to move. These daily movements are found in various plants within the Marantaceae family, they move their leaves up at night time, and lower them in the daytime in accordance to a circadian rhythm.
The movement is caused by changing the water pressure in the pulvini which are the nodes at the base of the leaves. The nodes are swollen to accommodate for the changing in pressure and subsequent movement of leaves. This action is performed when the amount of light being received by the plant drops.
What benefit comes from calathea leaves moving?
As mentioned above, calathea leaves move to reduce the threat of fungus and bacteria growing on the leaves. Traditionally a tropical plant, calatheas have evolved to withstand lots of rain. Throughout the day the leaves are open and collecting light however at night when this light isn’t available and there is no reason to keep the leaves open. The benefit of closing the leaves or having them point vertically is to reduce the amount of water sitting on the leaves, whether it was there from throughout the day or it has fallen at night time this water can stagnate and cause damage to the plant and encourage fungal and bacterial growth. This protective mechanism is one of the reasons why calatheas can grow in a thick bushy fashion and creates such a stunning style.
Why aren’t your calathea leaves moving?
If the leaves of your calathea aren’t moving the reason is likely one of the following:
– Not receiving enough light
– Not enough water
Now I know those 2 reasons are some of the biggest issues with any plant and it doesn’t help too much. But the fact remains if your plant isn’t healthy, it wont grow and perform as it should.
Let me explain further. If your plant isn’t getting enough light, it wont bother moving as it needs to get more so that it can thrive. On the other hand if your plant isn’t getting enough water it may not have the necessary pressure to make the leaves move.
So now you know all about why calathea leaves move. I hope this has helped increase your knowledge of your houseplants!