Washington Park Arboretum is open every day from dawn to 8pm, free of charge. Visitors Center is open limited hours. Japanese Garden is currently by appointment for $8
It's a park that has daytime hours and it costs nothing, though I'm sure they'd take a donation for upkeep.
Free, only the Japanese Garden costs anything($8)
Entrance is free.
$8 per adult, children under 5 free
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