SPRINKLER TALK FORUM - You Got Questions, We've Got Answers

Shaded lawn is where you'll have your trouble. It's generally where most molds/fungus will form anyway. Winds, for the majority, are also lighter at night and early morning. 95% of professionals agree, that early morning is the best time to water, for all the reasons listed in these posts. There are sites out there that simply have to water in the evening due to their size. Soils also play a huge factor. Clay soils that do not drain, will see above average mold/fungus if watered in the evening. Sandy soils have few issues.

more reasons to water in the mornings http://www.ipm.ucdavis.edu/TOOLS/TURF/MAINTAIN/irrwhen.html

I usually water in the afternoon around 5pm since I like to see my sprinklers working, and I have 6 zones, each 15 minutes each. I water 15 minutes each during spring and mild summer, and when the weather gets hotter, I pump it up to 20 minutes each. (But that's just me)

My yard is in the sun from 7am till about 5pm. I've always watered in the afternoon so it can soak in. Not once have I ever had a problem with mold, disease, etc.

The grass always has dew forming on it when it gets dark whether I water or not, and it dries out all mid day in the sun. End of day, I give it a good soaking.

Before I say anything, understand that the only plant I understand is grass and not much about that.
According to a local horticulturist, the early morning water time frame is more for bushes and flowers.
According to him, healthy grass is pretty hard to kill but water staying overnight on rose leaves and some other plant that's popular but I can't remember now contributes to plant fungus.

Or something like that.

Lawns got black fungus without there being sprinklers running, but if conditions favored such growth, early evening watering would have a lawn wet all night, as opposed to watering in the wee hours of the morning, with only a few hours of wet lawn.

According to Rutgers, not so. Which I think explains why it rains at night with not killing grass.

don't water at night. You're asking for lawn disease. Early mornings are the best.

According to Rutgers, one inch per week and 10 PM to 6 AM. Start there and adjust for your lawn.

What is a good time of the day to start watering and for how long should I run each zone in NJ?