Is it bad to water my trees late at night? The lady below me in my new apartment doesn't like water dripping off my porch so I wait till she goes to bed.

i've heard in general that it is a bad idea as it doesn't get heated by the sun and doesn't evaporate quickly cooling off the soil, also the cool damp condition attracts molds, fungus, and some pests such as slugs. Granted i don't know if all this is true, but from what i know it sounds at least plausible. So i guess its either do so at your own risk, or test the theory about if its bad and let us know.

I use automated system with several zones.

I schedule to water my container plants, shrubs and lawn, a couple of hours before sunrise. It is a good compromise to minimize evaporation and effects of fungal diseases.

For my veggies and blueberries that are shallow rooted, they are watered twice a day, short time, one at 9:30 am and the other at 2:00 pm to enable the plants to cope up with the dessicating California heat and the maximum evapotranspiration demand.

For my trees, my irrigation is underground and I water them just once every two weeks, but 6 hours run, and I set it to every other Friday midnight, so that by every other Saturday morning when guests comes, the trees are really plump.

It is setup like that to minimize diseases, minimize growth of weeds (with underground drips, I practically have no weeds under the trees, and so a lot less work), enable the plants to have water when they needed it most, to encourage deep rooting whenever possible, minimize interference with our family household water use, satisfy city ordinances, taking note of when neighbors water their yard (to make sure I have available pressure to cover lawns thoroughly without wasting water), adjusting the run times twice a month to cope with the seasons.