Lawn grasses should be watered in winter if you experience a couple of weeks with no rain. As a rule, grasses should have 1 to 2 inches of water per week, including any rainfall.
Your grass will tell you when it needs water. It will look dull and droopy and, when you walk across it, you will leave footprints.
Watering should be done early in the morning for two reasons: first, because there is less evaporation and second, because it gives your lawn a chance to dry before nightfall, which helps prevent diseases. Watering slowly, deeply and infrequently will encourage deep root growth.
Tall fescue, Kentucky bluegrass, and ryegrass are all cool-season grasses. That means they grow during cool weather, so that's also when they should be fed. Fertilize these grasses in late fall, winter, and again in early spring. A good feeding timetable would be October 1, December 1, February 1, and April 1. Most lawns do well with a 3-1-2 ratio of nitrogen, phosphorous and potassium; look for fertilizer labeled 12-4-8 or 15-5-10, for example. Don't apply fertilizer to wet or moist grass, but water immediately after.
Helen L. Sanders, Smith County Master Gardener
Texas AgriLife Extension Service