Yellow Grass: Winter Dormancy
It is entirely normal for grass to turn yellow as it transitions into winter dormancy after the first heavy frost or when overnight temperatures drop below freezing. Sod delivered in the late fall through early to mid-spring will likely be yellow to some degree. Keep in mind that our farms are open fields located in rural areas. So, grass coming from the farms will be further into dormancy than grass you see in suburbs and metro areas where the asphalt, houses/buildings, concrete, trees, etc., keep the soil temperatures warmer.
The dormancy transition is gradual, and the grass will continue to yellow fully when the soil temps stay consistently below 65° F. It is not uncommon for the grass to begin to green up if there are stretches of warm, sunny weather. When the temperatures bounce back and forth between warm and cold, the dormancy transition is often slowed/delayed. When we experience unseasonably warm winters, some varieties may not ever go fully dormant. In these instances, your lawn may remain a patchy mix of green and yellow, similar to hot spots in the excessive heat of summer.
It is important to note that most people that lose their lawn over the winter lose it due to a lack of moisture. As long as there is proper moisture, the water will freeze instead of the plant. Deeply saturating the soil 24 hours before freezing temperatures arrive will warm the soil and help insulate & protect the root system. When installing grass during winter dormancy, it is essential to avoid gaps by laying the grass as closely together as possible without overlapping. Laying the grass pieces seam to seam will help protect the roots from the freezing temperatures.
One perk of installing dormant grass is its reduced water requirements, you must keep it wet. However, you should make sure that you keep the top 2 inches of soil moist throughout the winter. Also, water requirements will depend on your soil type, soil temperatures, and weather. Please make sure to use the proper irrigation schedule based on fluctuating weather & your lawn’s needs. You can find these seasonal irrigation schedules in the irrigation article within our Grass Care page.
Finally, the grass will not have significant growth as it transitions into dormancy. It is likely that the grass will not fully establish its root system or have noticeable lateral growth when installed during the late fall through early spring. So, you will most likely not see the seams fill in until the spring when the sod enters its most active growing season. This is entirely normal and no cause for worry.
Common Causes:
- Heavy Frost/Overnight Freezing Temperatures
- Soil Temperatures Below 65°F
Resolution:
- Soil Temps Consistently 65°F & Up
- Proper Irrigation Throughout Winter
- Fertilization in Spring