Watering Your Lawn In Extream Heat.

How To Water Your Lawn 

How much should you water? How often? Proper watering is crucial to having the best-looking lawn on the block. Here are some key points:

• Your lawn needs at least 1”-1 ½” of water per week, year-round, during the winter, too.
• Water deeply 2-3 times per week, rather than daily.
• Water as early in the morning as you can, when possible.
• If you can’t push a 6” screwdriver into your lawn, you’re not watering enough.
• You will need to water more in the heat, especially if you have a fescue lawn.
• Don’t water so long that it runs down the street. 
• If you have automatic sprinklers, check them regularly to be sure you’re getting complete coverage.
• If a brown area doesn’t respond to watering, look for another problem.

Let’s go over these points. 

Your lawn needs at least 1"-1 ½ ” of water per week, year-round, during the winter, too. Lawns that are dry going into winter or during winter are more stressed and more likely to sustain winter damage. How do you know how much you’re getting? First of all, buy a rain gauge. If you get an inch of water in it per week, you’re cool. If you don’t, you need to water. (Bad news, if you live in Maryland. Our precipitation comes when we don’t need it – like when it’s 73°, never when it’s 100°.) 

How long should you water to get one inch? We can’t tell you that, because we don’t know what kind of sprinkler you have or what your water pressure is like. With automatic sprinklers, it’s usually one hour.  But you can measure that yourself. Just get a tuna can, which is 1” tall, (eat the tuna out of it, first) and place it where your sprinkler is hitting. Run your sprinkler and see how long it takes to get a half-inch of water in the can – just like a rain gauge. Usually, it’s about 30 minutes.  So 20 minutes, 3 times per week will get an inch of water on your lawn, and 30 minutes 3 times per week will get 1 ½” down. Bear in mind that during extreme heat, you will need to water more, due to evaporation and heat stress on the grass. 

Water deeply 2-3 times per week, rather than daily.  Watering daily will give your grass a shallow root system. Shallow root systems dry out fast and weaken your turf. Watering deeply 3 times per week will give your grass a deep root system, making it stronger and more drought-resistant.  

Water as early in the morning as you can, when possible.  Watering early in the morning will ensure that your lawn dries completely before nightfall. A wet lawn at night, on a regular basis, can lead to fungus and disease problems. Also, it’s cooler and less windy in the morning, so you have less evaporation, which will save money on your water bill and take less time to get the water on your lawn.   

If you can’t push a 6” screwdriver into your lawn, you’re not watering enough. Watering 1"-1 ½ ” per week is a guideline. Different soil types need different amounts. Soil is rarely composed of one type, but rather a combination of clay and sand, which makes loam. A sandy loam won’t hold moisture as well as a clayish-loam. Clay holds moisture better (think mud,) but the water is slow to penetrate it. You can tell what your dominant type of soil is by getting a moist handful and squeezing it. Clay will smush into a ball that doesn’t fall apart. Sand will stick together when squeezed, but not for very long. In Maryland, our soil is mainly on the clay side, unless you’re by a river or bay, and then it leans toward sand. High winds also dry out your lawn incredibly fast. 

You will need to water more in the heat, especially if you have a fescue lawn.  You may need to water more in the summer heat to keep your lawn from becoming drought-stressed, especially if high temps are accompanied by high winds. If we have extreme temperatures – high 90’s and over 100º - for a prolonged time period, you might want to 1) raise your mowing height a little too) water lightly daily to cool off the grass (this is especially true for fescue.) Grass needs more water during the heat because it also uses water as an internal coolant. Daily waterings in the heat should be in addition to your regular deep waterings. 

Don’t water so long that it runs down the street.  If water starts running down the street before you get your half-inch on there, turn off the water and wait for it to soak in, then resume watering. This might happen if you haven’t had time to water for a while. If it happens every time you water, either you’re waiting too long in-between waterings, or you may have a compaction problem. Compaction occurs in heavy clay soil or in high traffic areas. Aeration may alleviate the problem temporarily, but usually, you have to change the conditions causing the compaction for long-term relief.  

If you have automatic sprinklers, check them regularly to be sure you’re getting complete coverage.   Have you ever driven by a neighborhood entrance or along a business with nice landscaping that has this one sprinkler head aimed out at the street, and every day it’s on, spraying in the street, even if it’s raining – even if it’s freezing cold, and it’s making a nice icy spot on the road? Watch your sprinklers every once in a while to be sure you don’t have one like that!