|I live on a mountain with very rocky , clay soil. What kind of grass will work the best? It's also partially shade.|
|Perennial ryegrass is a cool-season grass and performs best at higher elevations (> 1000 feet). The most common use for perennial ryegrasses is in a mixture with Kentucky bluegrass where the perennial ryegrass component is less than 15 percent by weight. Fine fescues have the best shade tolerance of all the cool-season grasses and are often included in a mixture with various Kentucky bluegrass varieties. So for your situation, I'd get a mixture of perennial ryegrass, fine fescues and Kentucky bluegrass and you'll cover all your bases.
Best wishes with your lawn!