IS IT GOOD TO WATER A LAWN BEFORE A FREEZE?

Today's rain will help protect your lawn for tomorrow's freeze.   Many areas received over an inch of rain Monday night and Tuesday.  Orange Park got 1.06", Arlington 1.07", Mandarin 1.21", and St. Augustine 1.46".  Watering a lawn 24 hours before a freeze helps protect it from the cold.  It is important for the grass to not be dry and in need of watering.  A freeze on dry lawns is more stressful for the lawn but water will help insulate the roots during a freeze.

Grass will typically turn brown after January here on the First Coast.  This is expected and over watering will not bring back the green color. The lawn is not dead. In fact watering more than once every 10 days can promote fungus.  It is important to mow in winter even though the grass is not growing quickly because this keeps weeds in check and prevents them from dispersing seeds which will sprout during the spring.

However, watering foliage before a freeze could be more damaging than doing nothing. When a sprinkler system comes on during the freeze and turns off before the freeze is over, damage can be severe. University of Florida Master Gardeners say ornamental plants can be protected during a freeze by continually sprinkling the plants with water. Sprinkling must begin when the temperatures drop to 32ºF and must continue until the temperatures rise above 32ºF. Sprinkling must be such that the water is evenly distributed and ample enough to maintain a film of liquid water on all of the foliage surfaces.  This practice is impractical and not recommended for homeowners since home irrigation systems are inadequate for such extensive water delivery. Water pressure may drop if several homeowners in the same area turn on their systems, making adequate water delivery impossible. Several hours of irrigation may be necessary and this can cause soil saturation resulting in root rot. It also wastes large quantities of water.  A better method is to cover the plants with cotton sheets.

If after all your efforts the plants suffer freeze damage don't worry about trying to water them back to life.  The tissue is probably dead and not able to use the water to come back to life.