St. Johns River Water Management District and Southwest Water Management District limit watering to after 4 pm and before 10 am. Why is this? Why can you not just water your garden whenever you want? Last Water Wednesday, Jamie Daugherty, the Residential Horticulture Agent in Lake County, explained why from Plant Physiology perspective.
“The goal is water conservation. A lot of water is lost to evaporation in the hottest parts of the day. Additionally, most plants are not absorbing significant amounts of water during the hottest parts of the day. This is because the rate of photosynthesis decreases with increasing temperatures. At approximately 104oF the process stops all together. Plant physiology also plays a key role in why watering should be limited to before 10 am and after 4 pm. When plants convert the energy from sunlight into sugars, they need water and carbon dioxide. Since the rate of photosynthesis declines with increased temperatures, most plants will be using less water in the hottest parts of the day.”
To watch the Water Wednesday recording: