We don’t really need to fertilize or add fungicides to our lawns for the next few months, but that doesn’t mean they won’t need water. And since watering questions have come up in emails and some Facebook posts recently, I think irrigation is a great topic for this week.
Nick G. in The Woodlands wrote, “Hey Randy, with the weather cooling and days are shorter, that means the lawn no longer needs water, right?” And Sara E. in Cypress asked, “Randy, what is your recommendation for watering the grass during the winter months?”
To answer Nick, WRONG! As for Sara’s question, keep reading.
Remember that for turf, trees, perennials, and shrubs to stay healthy year-round, they always need water. Even dormant and deciduous plants need some. With a little helpful rainfall, we won’t need to water them as much as in the summer, but their roots will still need moisture through the winter months.
And if you want your lawn to stay healthy and respond quickly at the first whiff of spring, you’ll need to heed some winter irrigation advice. But as I’ve said before, there is no one-size-fits-all answer for everyone.
One assumption I will make is that you weren’t bone-headed enough to put out winter rye. If you did, and you want to keep that grass green and thriving for the next three months, it’s going to require a lot of irrigation. And fertilizing. And mowing! And if you didn’t set up winter rye perfectly, you’ll wind up with the equivalent of a balding man's "comb-over." Everyone who sees it knows something’s not quite right while the comb-over guy thinks it looks good.
If you are letting your St. Augustine, Bermuda or zoysia grass go dormant (as you should), here are some basic watering rules to live by during the winter months.
- Turf normally needs 1-1 ½ inches of water per week when temperatures are normal. In the winter, though, it can survive on 1-1 ½ inches every 2 or 3 weeks
- If you like to turn your irrigation system off in the winter, especially on freezing nights, remember to turn it back on for warmer days. That's extra important if it’s been more than two weeks since a significant rain.
- Yes, Mother Nature can provide that 1-1 ½ inches over 2-3 weeks in the winter.
- Root systems are still very much alive and need moisture.
- Too much moisture can lead to brownpatch if temperatures are between 80 and 60 degrees.
- This is a great time to have your irrigation system checked for leaks and potential problems.
- Two or more months with no rain or irrigation can kill a lawn.
- In the event of a freeze advisory, be sure to water deeply a full day before it’s forecast to hit to fortify your plants and flowers. It takes longer for well-watered plants to freeze. (Be sure you protect backflow valves on the night of a freeze, though.)
If you put these protocols in place and follow my fertilization schedule, you’ll bounce back with quick results by late February.
By the way, I’ve also been asked many times if watering grass with a hose and sprinklers is less expensive than using an irrigation system. Well, 23 years ago I was “hose dragger,” but today’s smart irrigation systems are more cost-effective than ever. Professionally designed systems use sensors that only allow watering when conditions require it, and studies have shown that proper irrigation can offer water bill savings of up to 20% every month, compared to watering with a garden hose and an impact sprinkler. The rotating nozzles in professional irrigation systems spread heavy droplets of water at a slower pace, which makes them more targeted and effective. Moreover, irrigation systems run on timers - if you forget to move a hose because you're engrossed in a football game on TV, you’ll wind up wasting money, not just water.