Here is the scoop on questions and answers you and your master gardener volunteers receive about tall fescue. A. Tall fescue grows best in areas which are 3500 feet to 7500 feet in elevation. Generally yes, but not on a shallow soil, or a thin layer of soil on tip of caliche or rocks. Tall fescue avoids drought by having a deep root system. The deep roots can extract water from a greater amount of stored soil water.
Tall fescue can go more days between irrigations or rainfall than ryegrass or Kentucky bluegrass.
At higher elevations it can go 10-12 days between irrigations after a 2.0 inch rain, but we generally do not have enough rain or deep soil for tall fescue to act like it does in the midwest. You will end up with a patchy lawn with clumps of tall fescue among bermuda. This is an unthrifty condition which often results in scalping. Apply two applications ten days apart. Don't wash off the round-up from the leaves.