If you were to take a map of the globe and draw a parallel line to the east and to the west of Florida — worldwide — what would you discover?
You would note that Florida is roughly positioned along the same latitude as Mediterranean-type climates where dry, arid conditions prevail. Logic implies then that our weather should be more like that of Southern California or parts of the Mediterranean; hot and dry.
In a normal year, Florida is especially known for its hot, but very wet summers. Because Florida sits between two large bodies of water, it has the luxury of moist, humid air riding along the sea breezes being pulled in our direction just looking for a piece of land on which to rain.
Florida averages 50 inches of rainfall per year as opposed to Southern California at 15 inches to 20 inches annually.
But, from October to April or May, Florida can be very dry.
That’s a typical dry pattern for us based on our latitude, so even sticky, swampy Florida is meant to dry down. In our landscape, this can pose some issues, but maybe not the ones you’d expect.
Our trees and shrubs, once established, require little to no supplemental irrigation throughout this typically dry period, because they are adapted to this seasonal variation.
There is one caveat, though: These must be the right plants in the right place.
A plant out of place, say a shade-loving plant in partial to full sun, will obviously require more water to survive if it’s going to do so.
Put that shade-loving plant in a shady spot where it’s meant to be, and we prevent stress, thus lowering water needs.
Newly planted shrubs and trees would certainly require more water during the dry season, so that’s why it’s best to hold off on planting until we begin our warmer, wetter season in May maybe even June, so that frequent irrigation won’t be necessary. Let nature do the watering for you.
Turfgrasses, like St. Augustinegrass (‘Floratam’ is an example), are a bit different. St. Augustinegrass will enter a semi-dormant phase in Central Florida due to the shortened day-length of fall and winter. It’s not actively growing, but it’s not totally dormant either, so it does need some water to stay alive.
When it’s dry during the winter, it’s common to see symptoms of drought on this grass. Rolled leaf blades, a bluish-purple cast, or footprints left behind as we walk on the turf are all symptoms of drought and require supplemental irrigation. Conversely, in the summer, if your turf is established and healthy, it’s unlikely you need irrigation at all, as long as we’re getting frequent rainfall like we normally do.
Be aware that too much water could actually cause more harm than good, and certainly wastes valuable water any time of the year.
As we continue through the dry season, monitor your turf for drought stress and irrigate late in the evening to prevent evaporation losses, and use no more than three-quarters of an inch of water per application.
In Pasco County, water restrictions limit homeowners to one irrigation event per week, so make the most of it, and irrigate appropriately.
When asked how much irrigation a homeowner is applying, the most common response is 10 minutes or 15 minutes.
Ten minutes to 15 minutes of irrigation, depending on your irrigation system and the nozzles, might mean that you’re applying 1/10th of an inch to 2 inches or more of water.
The only way to be sure is to calibrate the system, which is easy. Take two tuna cans, or three, and place them in each irrigation zone. Run the zone for a set period of time. Measure the amount of water in the can, and if you’re putting out more or less than the three-quarters of an inch recommended, simply adjust the timing on that zone and retest.
Test each zone. Check for broken or nonfunctional heads. Also, look for heads that are pointing onto pavement, sidewalks and so on, because they are doing nothing more than wasting water and your money.
A simple calibration check every three or four months will prevent a lot of turfgrass woes and save a lot of dough.
Also, remember that your grass is not actively growing through the fall and winter, so fertilizing during the dry season of late fall through early spring is useless, as the plant will not use the fertilizer, and what remains of it is leached into the groundwater leading to senseless pollution. Plus, it’s a waste of money. We don’t want to tell our plants to grow when nature is telling them to rest. There’s a reason they’ve slowed growth or gone dormant, so don’t interfere by overwatering or fertilizing during these times of drought.
If you have questions about helping your landscape cope with seasonal drought, call your local University of Florida/IFAS Extension Office for help. We have Solutions for Your Life.
Dr. Whitney Elmore is the UF/IFAS Pasco County Extension Director and an Urban Horticulture Agent III.
Published January 11, 2017