9am - 4pm (gates close at 3pm) Tues-Thurs, Sat, Sun as well as on Monday and Friday if those days fall on a national holiday Closed most Fridays and Mondays, December 25 - January 3 and for imperial functions
Added to JGarden:
This garden is known for its irises, azaleas, pines and cherries. It has a nice view over the city the old fortress site of the original palace. Enter the garden from the Otemon Gate to the Palace, near the Palace Hotel.