As long as you would like
Self guided so will depend on you/your group and how crowded it is. Recommend during the week if you can
although they offer some tours, we have always simply wondered the gardens. most can be seen in an hour, but depending on time of year you might wish to stop and sit. we always leave at least two hours. without touring the house or watching the movie. just relax and enjoy.
There are scheduled docent tours every month. About an hour. Private tours are available. Check the website.
It depends on your mood. It's big and there's so many things to see - gardens and the mansion and the gift shop. When we go, it takes us a few hours because we take the time to sit and relax and enjoy the beauty that we see. You can bring a blanket and lay it on the grass and relax as well.
2 hours is plenty of time. We did it in 1.5 hours.
2 hours of house and garden. Another 30 min if you include the trail walk
About two hours
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