botanical garden - a facility where trees and shrubs are cultivated for exhibition. arboretum. facility, installation - a building or place that provides a particular service or is used for a particular industry; the assembly plant is an enormous facility.
Keystone, CO Weather. The average temperature of Keystone is 35.80Â°F, which is much lower than the Colorado average temperature of 46.26Â°F and is much lower than the national average temperature of 54.45Â°F. Historical Weather.
The Zipcode for Keystone is. Keystone is in Summit, Colorado in the South West region of the USA. It is located about 51 miles west of CO's capital city of Denver.