Depending on the fall weather and rain frequency you will likely set your sprinklers to water less frequently or even turn them off for a while. It's still important to check outdoor plants to make sure they have enough water. While they need less water when it's cool, it's important to make sure they don't dry out. If you have a lawn and rains haven't come, irrigate the lawn once or twice this month.
If it has been raining, the soil may be saturated so be careful if you have to walk on it so as not to compact it. Also if soil is waterlogged, vital space for air that is needed for plants and worms and excess water can drown beneficial soil organisms and contributed to rotting roots.