Source: The Castaic, CA weather data displayed above is derived from the NOAA (National Oceanic and Atmospheric). Air quality and pollution data is derived from the EPA (United States Environmental Protection Agency). Air quality and pollution levels measured in a particular area may not be representative of the entire county.
Plant fescues when fall temperature reach about 75 F. The next best time to plant fescue seeds is when rising temperatures in spring reach 60 F. Summer isn't a good time to plant fescue lawns, because fescue grass tends to go dormant during periods of high temperature.
Cool season grass such as Fescue, will germinate best when the soil temperatures are between 50 and 65 degrees F. These soil temperatures usually occur when the daytime air temperatures are between 60 and 75 degrees. The fescue grasses, when planted properly, germinate within 10 to 14 days.