Spitting water: Because of the weak transpiration, the water absorbed by the root system overflows from the drainer, and the water droplets are integrated and appear at the tip or edge of the leaf. This phenomenon is spitting water, which usually occurs at night or in the warm and humid morning. Water droplets appear at the tip and edge of leaves, which can be used as a sign of normal root activity.
There is a small hole at the tip or edge of a plant leaf, called a water hole, which communicates with the conduit for transporting water and inorganic salts in the plant. Water in plants can be continuously discharged from the body through water holes. Usually, when the outside temperature is high and the climate is dry, the water discharged from the water holes will evaporate quickly and disappear, so we can't see any water droplets accumulating on the tip of the blade. If the outside temperature is high and the humidity is high, the high temperature makes the root system absorb strongly, and the humidity inhibits the evaporation of water from the pores, so the water has to flow out directly from the water holes. In plant physiology, this phenomenon is called "water spitting phenomenon". The phenomenon of spitting water is most easily seen in the early morning of midsummer, because the high temperature during the day makes the root system extremely absorbent, while the transpiration at night is weakened and the humidity is high.