Winter watering is perplexing. If you have shrubs and trees that have been planted in the past year or two, you should give them a good soaking with a garden house if there is no rain at least twice a month to get water to the roots. Remember, the root systems on those trees and shrubs is only as large as the container from the nursery. Water with the weather. If your turfgrass is dormant, I would not water it more than once a month. We have not had any rain here since October, so things are very dry. I have Sandy soil and it is just like powder about 18 inches down, so i am running sprinklers on my fescue lawn in the backyard now. I dig down and check soil moisture.