The most common problem with landscapes that are maintained by maintenance gardeners is excessive irrigation. In fact, with very few exceptions, the only lawns that are maintained by gardeners that are not also irrigated excessively are too dry because the irrigation systems are not operational. Excessive irrigation is not only unhealthy for the landscapes, but costly.
Wasted water is obviously expensive, but also causes all sorts of expensive damage. Saturation of soil inhibits deep dispersion of roots, causing shallow roots to displace pavement. Shallowly rooted trees that are easily destabilized by wind can cause expensive damage, and are expensive to remove. Smaller plants that do not cause damage as they succumb to saturation and rot are still expensive to replace. The gardeners who get paid to maintain the landscapes should assume liability for the damages they cause, but instead charge to repair it! If they can not repair the damage, they typically happen to know someone who can.
Fortunately, those of us who maintain our gardens, or are at least involved with the maintenance, are not so generous with water. Although lawns need quite a bit of water, they also need adequate drainage. Besides, we tend to be more aware of the expense of water than gardeners are.
Now that it is autumn, irrigation needs to be decreased for various reasons. Rain will be providing more moisture as the seasons progress. While the weather gets cooler and more humid, and the days get shorter (less sunlight) not so much moisture evaporates. Most plants are either dormant or at least less active, so consume less moisture.
There are unfortunately no accurate formulas for decreasing frequency and duration of irrigation as the weather changes. It must be done by trial and error, by providing enough irrigation during dry spells without keeping conditions too wet. Of course, no irrigation is necessary during rainy weather, except only for plants that are sheltered by eaves. Hanging pots should be monitored because they are both sheltered from rain (if hanging from eaves), but also exposed to drying wind.
Also during autumn and winter, dormant plants need no fertilizer. That can wait until they wake up early in spring. Raking falling leaves from lawns, ground cover and low shrubbery is important though, since such debris shades the plants below while sunlight is already less abundant, and can also promote rot.