This phenomenon is very normal. There is a more professional way to call it night sports. The main reason for this is the change of light, because the leaves feel different light in the daytime and at night. It is photosynthetic in the daytime, so the leaves will be stretched out as far as possible, so that the absorption of light will be slightly increased, and at night it will be closed, so that the loss of heat and water will not be very serious.
Generally, there is more than one plant with this phenomenon. Some legume plants, such as peanuts and Albizia flowers, etc., will occur. In addition, there are some other families, such as Oxalis, which will also occur.
In fact, this kind of phenomenon is still beneficial. It can let us judge whether the plants grow healthily. For example, if this kind of plant is very healthy, its leaves will start to close in the evening when it moves, but if it is ill or its environment is not suitable for it, its night sensitivity will be much worse.
The reason for this phenomenon is that the cells in its leaf pillow will expand periodically, so it will change. In the daytime, it will absorb more water, grow up, and the leaves will exhibition, and at night, the upper leaves will lose some water, and start to close.
All in all, this is a very normal phenomenon, we don't need to worry about anything, only when we find that this kind of grass doesn't close in the evening, we need to start worrying about it. At this time, we can consider changing it into a better environment, if it is sick, we can consider treating it
