Late Blooming Sakura
If you missed the peak of the sakura (cherry blossom) season, you can still catch the “satozakura” (里桜) at Takasaki Shizen no Mori, a park in the far south area of Tsukuba (formerly Kukizaki). These flowers bloom later than the standard “someiyoshino” variety, so they are just reaching their peak now.
Take Tsukubus 12 and get off at #37 Takasaki Iriguchi (高崎入口).
Address: Takasaki 1078-1 (click for map in Japanese)