But that's not all. When stomata are closed, a plant is not pulling water from its roots, up through its veins and into its leaves, which further contributes to the "stressed" appearance of the plants. Without water transpiring through open stomata, nothing is being drawn up from the root zone, including nutrients. Without nutrients growth is slowed and flowers and fruit may even fall from the plant, a common complaint of those who grow summer tomatoes.
By understanding how water is used in plants, you will be able to use it more wisely. Often, more water applied to the roots may not help. Maybe just a spritz is all the plant needs.
RON VANDERHOFF is the nursery manager at Roger's Gardens in Corona del Mar.
Question: Last year I went to the OC Master Gardener fall Gardening Seminar in Huntington Beach. When is it this year?