Hanami is one of the most revered and anticipated seasons in Japan, and the Satte Sakura Festival held in Gongendo Park is definitely one of the more attractive and picturesque views on the rural side of Tokyo. Contrasting a lush yellow rapeseed blossom field with gorgeously rich pink Cherry Blossoms, it is a sight to behold.
Starting in early February and ending at the beginning of May, Hanami (花見) is the celebration and event of viewing flowers, and you will predominantly see the Cherry (桜 or Sakura) blossoms and the lesser common Plum (梅 or Ume) blossoms around this time. In Tokyo, it usually happens towards the end of March to early April, and usually, the Cherry Blossom forecast (桜前線 or Sakura-zensen) will predict the anticipated dates of full bloom.
Daytime parties are obviously frequent during the weekend, but evening Hanami parties (aka 夜桜 or Yozakura) are also a regular affair during the weekdays for full-time employees, keen to get amongst the celebratory action.
The Satte Sakura Festival, similar to many venues, also has rows of Food stands (屋台 or Yatai) along the thousand or so Cherry Blossom trees that line the entire 1km stretch of the park. Under the shade of the glorious pink petal blossoms, people have set up chairs, mats and all kinds of contraptions to celebrate the coming of the Sakura and also to welcome in spring.
Satte or Minami-Kurihashi station is about an hour and 15-minute train ride on the Hanzoumon line from central Tokyo station. It is then maybe a 10-15 minute taxi ride to Gongendo Park, of course, if you prefer the hike I recommend getting off at Minami-Kurihashi station as it is a shorter 30 minute trip on foot.
The Satte Sakura Festival is definitely one of the more scenic and photogenic places to enjoy Hanami, especially on the outskirts of Tokyo. I would definitely recommend it as a spot to check out during the Sakura season!