Sarah,

Thank you for your question.  How much to water a Colorado lawn is influenced by many factors.  Here is Colorado State University's help sheet on Lawn Care.  Note that the age of your lawn, how much sun the area receives, soil compaction, your use of fertilizer and how often you mow are things to consider.  A bluegrass lawn does require more water than some other species, especially in hot weather, as we are experiencing this August.  

During hot, dry weather, it is especially important to irrigate your lawn between 10 pm and 6 am to reduce evaporation and lessen the onset of disease as stated in the help sheet, Watering Established Lawns.  This resource goes into the details about how much, when and how often to irrigate your lawn.

I hope you find these resources useful.  

Sincerely,

Sue

Master Gardener Help Desk, Horticulture

Colorado State University Extension, Jefferson County

jeffcoextension.org

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