It totally depends on you-- the gardens are self-guided. You can set your own pace. I would say if you want to take in everything, talk to a volunteer in the visitor center, see what events are going on in the conservatory and view any art displays, read botanical signs, see all the gardens, check out statues, and take pictures, give yourself at least two hours, or more if you plan to eat or sit and relax during your touring. Otherwise, take a walk, look around, maybe only spend an hour.
I agree with others one to two hours. Lots of mosquitoes in the woods!
Couple of hours.
Anywhere from 1 to 2 hours
I would say allow 2 hours. It's all walking, so depending on how fast you walk, and how long/ often you linger, it could take certainly more, or less time than that.
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