Type your question here!

Sunday, April 9, 2017

Droplets on Plants May Be Guttation

Q. I have never seen this on a plant before and I have never had a problem with pests on this plant.  What am I dealing with here? 

A. Great pictures, that helps a lot. I am going to take an educated guess that this is water being released from small openings on the leaf edges called hydathodes. The release of excess water from inside the plant is called guttation. You can read more about hydathodes here.

What is gutational water?

These can be very complicated explanations and I don't know about your background and whether they will confuse you or if you understand them. Basically, small plants can push a lot of water inside of them through a mechanism called root pressure. Root pressure takes water from the surrounding soil, if there's plenty of it, and push it inside the plant. Sometimes the root pressure can be so great that the plant needs to release some of this excess water. Many plants have specialized openings on the leaf edges called hydathodes that allow it to do this. Technically, the process of taking excess water inside the plant and releasing it through hydathoes is called guttation.

Back in the day….

Golf course superintendents are very familiar with this but may not know the correct scientific terms. Years ago golf course superintendents would go to the putting greens early in the morning and "whip the greens" with a long bamboo pole. It was found when plants are growing very close together in places like golf course greens that this excess water, guttational water, could encourage diseases if it was not removed from the leaf blades. They used to call it dew but the main problem was from guttational water full of plant sugars and a good "food" for plant diseases.Whipping the greens with a bamboo pole knocked the water off of the blades of grass and reduced the possibility of disease. Very few whip the greens anymore but instead they use a short irrigation cycle to wash off the leaves of guttational water (which is high in plant sugars and disease prone) and replaces it with irrigation water which has no sugars in it.

So what does this have to do with you? 

If this is guttational water it simply tells you that the soil is full of water. Little leaf Cordia is a desert adapted species and does not have to be irrigated frequently. It tells you that the soil around these plant roots is full of water and you may or may not be watering too much if you see this water present frequently. Make sure that you give the plants a "rest period" without water before the next irrigation. Other than that, nothing to worry about.

No comments:

Post a Comment