Lawn Care When It Just Won’t Rain

Many turfgrass yards, including mine, are feeling the effects of an extended droughty period this month.  While one of the benefits of the primary turf species grown in the area (Centipedegrass, Zoysiagrass, Bermudagrass, and Bahiagrass), is their drought tolerant nature, they aren’t impervious to drought.   Even with these tough grass species the difference between a yard coming out of a drought in decent shape versus dead is as simple as remembering the answers to the following four maintenance questions.

How much should I water to keep my grass alive?

Lawngrass needs about ¾-1” of water per week to remain looking its best and growing vigorously.  Obviously, unless you have an irrigation system, keeping a large yard of turfgrass in that ideal water range is going to be hard or impossible.  So, what to do?  I encourage homeowners to focus their efforts on keeping grass around highly visible and often used areas of the yard well-watered, letting outlying areas fend for themselves until rain resumes.  To ensure you’re putting out the optimal ¾-1” of irrigation per watering event, spread a few straight sided cans (tuna or cat food cans work great) under the sprinkler’s range, allow it to run until you reach the 1” mark, and note how long it took to apply that amount of water.  This will help you dial in your watering and ensure water isn’t wasted.

Should I mow during a drought?

We all know that an unmown yard looks unkempt.  However, given that mowing is a major stress on turfgrass, mowing during a drought can weaken your yard’s ability to recover when the drought ends.  If you must mow to keep things looking neat, try to mow only areas that you keep watered and raise your mower’s deck to reduce the amount of leaf tissue you cut from the grass.  Mowing in this manner will reduce stress on your turf and keep the yard from appearing weedy and unkempt.  My unirrigated Centipedegrass yard has been flowering and setting seed over the last few weeks.  My last mowing event (during the current dry period) was designed to only remove seedheads and minimize removal of leaf tissue.

Unirrigated Centipedegrass turf showing drought stress – photo courtesy of Daniel Leonard.

Should I fertilize?

This one is easy!  Don’t fertilize grass during a drought!  For one, fertilizer promotes growth, and grass isn’t trying to grow during a drought, simply survive.  Fertilizing in these times is another unnecessary stress.  Additionally, fertilizer requires water to transport nutrients down to the plant roots.  If there is no water to do so, it will simply sit there and wait on rain.  Also, some or all the nitrogen in the fertilizer applied will volatize and return to the atmosphere, wasting your time, money, and effort and stressing your turfgrass in the process.  Hold the fertilizer until rain begins again.

What do I do about weeds?

Turfgrass isn’t the only thing stressed during droughts; weeds are as well.  During stressful events like droughts, all plants (weeds included) stop growing and enter survival mode.  This has major implications for weed control, as herbicides are not particularly effective on weeds with drought defenses up.  In addition to being ineffective, herbicides can injure stressed turfgrass, preventing a healthy recovery post-drought.  So, keep the herbicide off the yard until the weeds, and your turf, are happy and growing again.

Maintaining an unirrigated lawn during drought is more about what you don’t do – less mowing and no fertilizer or herbicide applications – than what you do.  Mowing too low, applying fertilizer, and trying to control weeds with herbicide are all potential stressors of turf and can inhibit its recovery when the rain returns.  The best you can do to keep your lawn healthy in dry times is to apply ¾-1” of water per week and pray for rain!  For more information about lawn management or any other horticultural topic, contact your local UF/IFAS County Extension office.