Has a hundred thousand of Azalea flower in 40 different varieties, covers the 35000 square meter garden at Omuroyama Park, Izu. 

April 29th(Sat)  - May 5th(Fri) 2017
9:00 AM - 16:00 (4:00PM)

Location: Eastern Izu, Izu peninsula, Shizuoka prefecture

Admission is free.
(Paid for car parking)

Getting there:
From JR Ito Station, take a bus bound for Omuroyama Lift. (25 min ride)
OR
From Kawana Station on the Izukyu Line, it takes 20 minutes on foot.

Related website
Mt. Omuroyama Lift (Japanese website)
http://omuroyama.com/

Azalea Festival Information by Ito City (PDF, Japanese)
http://www.city.ito.shizuoka.jp/kankou/komuroyamatsutsuji2017.pdf

Related article on digi-joho TOKYO:
Attractions in eastern Izu area