I have been there in June and watching the leaves go through the process was awesome.
April through October, is the planting and harvest seasons. Plan to stay about 1.5 hrs to see and do everything. Highly recommend a visit.
I was there in July and I would suggest that you go when the weather is nice. Mornings I would say every hour a tour goes out in the trolley, starting around 10:15. The rest you would have experience on your own. Nice outing.
We visited on early July and it was perfect.
July and August can be unbearable heat and humidity.
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