The wisteria at Kameido Tenjin Shrine (亀戸天神社) were planted during the Edo period and now the purple flowers hanging from the trellises in the Japanese garden are a major draw from mid-April to early May. During the Fuji Festival, the wisteria are lit up between sundown and midnight, but the lights in certain areas go off at 10pm so best to get there in the late evening for the full experience. You can also find several stalls around the grounds of the shrine during the festival.
Event details are taken from official sources whenever possible. It is always prudent to check the official event website before attending to make sure that there have not been any changes. If you know of an error in the calendar, then please let me know through the contact form.