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.
A soil temperature range of 50 to 65 degrees Fahrenheit, with air temperature of 60 to 75 degrees, is ideal for germination of fescue. Fescue grass will take as little as seven days to germinate, but it can take as many as 21 days for maximum germination. Keep the seedbed moist for best results. Planting grass seed on a well-prepared site with good soil and drainage will produce a light green, thin lawn in a week.