Great Gardens: Tromso Arctic Garden, Norway

The Arctic-Alpine Botanic Garden (Arktisk alpin Botanisk hage) is the world's northernmost botanic garden. It is located in Tromsø, Norway, and is run by the Tromsø University Museum. It opened in 1994, and is open from late May to early October. The garden displays Arctic and alpine plants from all over the northern hemisphere. Entrance is free of charge.

The garden is located to the southeast of the University of Tromsø Campus, commanding a view of the mountains to the east and south. The location, corresponding to the north coast of Alaska, invites thought of an extreme Arctic climate. However, a branch of the Gulf Stream sweeping up the coast of North Norway provides a moderating influence, and the climate of Tromsø is one of relatively mild winters (January average −4.4 °C (24.1 °F)) and cool summers (July average 11.7 °C (53.1 °F)).

From May 15 until July 27, the sun is continuously above the horizon in Tromsø. The two months of midnight sun provide some compensation to the plants for the short growing season and the low temperatures. In the months of May, June and July the theoretically possible number of hours of sunshine is 623, 720 and 695, respectively. The average hours of actual sunshine is about 200 for each of these months. From November 21 until January 17 the sun never rises. Snow generally covers the ground from October or November on, and will accumulate until the beginning of April. Snow then gradually melts and the ground will usually be bare around mid May at sea level, while lingering on far into the summer at higher altitudes. The season in the Botanic Garden is usually from end of May until mid October
(Wikipedia)