Q. We have lived in the
same house in Las Vegas for the last 42 years and every June my lawn has the
same problem. The lawn is a mix of common and hybrid Bermudagrass. First the
grass turns grayish (in patches) and then it turns brown. It slowly comes back
by September. I water according to local recommendations, use Scott’s Turf
builder 3 to 4 times a year and use Ortho Bug-B-Gone insect granules twice a
year.
same house in Las Vegas for the last 42 years and every June my lawn has the
same problem. The lawn is a mix of common and hybrid Bermudagrass. First the
grass turns grayish (in patches) and then it turns brown. It slowly comes back
by September. I water according to local recommendations, use Scott’s Turf
builder 3 to 4 times a year and use Ortho Bug-B-Gone insect granules twice a
year.
A. If this were tall
fescue I might be tempted to say this is a disease problem. However, since it
is a mixture of Bermudagrasses I think this is an irrigation problem. This will
be particularly true if these problem areas are in the same locations every
year.
fescue I might be tempted to say this is a disease problem. However, since it
is a mixture of Bermudagrasses I think this is an irrigation problem. This will
be particularly true if these problem areas are in the same locations every
year.
 |
| Turfgrass or lawns will turn a smoky or grayish green when they are not getting enough water. This is because the leaf blade either folds in half or roles depending on the grass. This creates a different color; smoky or grayish green |
Bermudagrass in our climate doesn’t develop many insect
or disease problems.
or disease problems.
The success of lawns in our desert climate is directly
tied to the quality of an irrigation system. In technical terms we say the irrigation
system should provide head to head coverage; water from a sprinkler head should
be thrown far enough to reach the head to its right and it’s left. If we don’t
provide this kind of uniformity in the design and installation of an irrigation
system it can result in brown patches that don’t receive enough water.
tied to the quality of an irrigation system. In technical terms we say the irrigation
system should provide head to head coverage; water from a sprinkler head should
be thrown far enough to reach the head to its right and it’s left. If we don’t
provide this kind of uniformity in the design and installation of an irrigation
system it can result in brown patches that don’t receive enough water.
 |
| A close-up of the grayish green color where the lawn is not getting enough water |
The water pressure in the sprinkler system should fall
within a range recommended by the sprinkler manufacturer. If the water pressure
is too high or too low it will affect the distribution of water and create
browning of the lawn in the same areas year after year. Otherwise, there are
sprinklers now that will lower the water pressure before the water is applied
to the lawn.
within a range recommended by the sprinkler manufacturer. If the water pressure
is too high or too low it will affect the distribution of water and create
browning of the lawn in the same areas year after year. Otherwise, there are
sprinklers now that will lower the water pressure before the water is applied
to the lawn.
 |
| Another indicator of drought or lack of water in a lawn are footprints. If you walk across grass that needs water, look behind you. If your footprints remain in the grass does not spring back quickly, the grass needs water. |
You can correct this problem in the short run by
increasing the number of minutes that you apply water. This delivers more water
to the dry areas. Unfortunately, it also delivers more water to the wet areas
resulting in overwatering of the green areas.
increasing the number of minutes that you apply water. This delivers more water
to the dry areas. Unfortunately, it also delivers more water to the wet areas
resulting in overwatering of the green areas.
It is also a good idea to punch holes in the lawn with an
aerating machine in the spring, particularly in the brown areas. This helps
water to move into the soil and not run off into low spots if there are any.
aerating machine in the spring, particularly in the brown areas. This helps
water to move into the soil and not run off into low spots if there are any.
Bermudagrass is notorious for building up “thatch”. Thatch
is a buildup of old grass stems and debris under the surface of the lawn but on
top of the soil. Years ago this thatch was burned off of the lawn with fire. We
can’t do that anymore. We must do it mechanically now.
is a buildup of old grass stems and debris under the surface of the lawn but on
top of the soil. Years ago this thatch was burned off of the lawn with fire. We
can’t do that anymore. We must do it mechanically now.
 |
| A core aerifier for lawns pulls plugs or cores out of the lawn that are about 4 inches deep. This type of verification provides better drainage and water penetration for lawns suffering from drought |
It is important to dethatch Bermudagrass each year. This
is usually done in the fall when overseeding it with a cool season grass like
ryegrass to maintain a green winter lawn. If the lawn is not overseeded in the
fall then thatch can be a huge problem in Bermudagrass.
is usually done in the fall when overseeding it with a cool season grass like
ryegrass to maintain a green winter lawn. If the lawn is not overseeded in the
fall then thatch can be a huge problem in Bermudagrass.
 |
| D thatching machines, sometimes called vertical mowers, pull debris from a lawn which allows water to better penetrate the soil and reduces runoff. |
Making changes to the irrigation system will correct some
of this problem and reduce the amount of water needed to keep the lawn green. Increasing
the number of minutes you apply water during the heat of the summer should
solve this problem in the short run.
of this problem and reduce the amount of water needed to keep the lawn green. Increasing
the number of minutes you apply water during the heat of the summer should
solve this problem in the short run.
But I would combine this with lawn aerification every
three or four years and dethatching every year to improve the amount of water
entering the soil in the dry areas.
three or four years and dethatching every year to improve the amount of water
entering the soil in the dry areas.