
17/11/2024
Guttation happens at night when plants close their stomata (pores) in their leaves because of the cool temperatures, but the flow of water left over from the transpiration is still in force. There are special overflow valves called hydathodes at the ends of the veins that can release the water pressure. This results in evenly spaced drops along the leaf margins. It is not the same as dew, which is a condensation of water in no particular pattern on the plants when the dewpoint is reached with the right combination of temperature and humidity.
Read my Transplanted Gardener article, “Water science and gardening,” for more details on how plants and water interact and how gardeners can take advantage of this knowledge. http://www.sky-bolt.com/garden/waterscience.htm