A very important question was raised just the other day...we know how long and how often we need to be watering, but when is the best time of day to water?
This is a great question because if you get this wrong, you are likely wasting a LOT of water. To get the most bang for your buck, all of your watering needs to take place in the wee hours of the morning. You want to try and start your waterings sometime after midnight, and try to finish as close to sunrise as possible. This means that start times will vary depending on your run times and number of zone you have. But always start with the goal to finish at sunrise and work your way backwards to figure your start times.
For example, sunrise right now is about 6:30am. If I have six zones that run for 35 minutes each, then I have 3.5 hours of total run time. That means I need to set my start time for 3:00am, and I will be done watering by sunrise.
Why is this so important? For two main reasons...first, the early morning time frame is the calmest, least windy time of day. So you won't have near as much wind drift while trying to water.
Secondly, this minimizes evaporation. Remember that we are not trying to water just the surface of the grass, we want a deep watering that soaks into the soil and reaches the root system of the turf. Watering in the middle of the day when it's 90+ degrees out will result in quick evaporation before the water has a chance to soak in.
The hotter it gets, the more important this is...so check your sprinkler systems and get this right!