I had the opportunity to visit the Missouri Botanical Garden and the Seiwa-en ("Garden of pure, clear harmony and peace"). The 14 acre garden was created in 1977 and is one of the largest in North America. It is rated #13 in the top 25 list published by Sukiya Living (The Journal of Japanese Gardening). Personally, I thought it was one of the best I've seen in the United States. Note: the morning I visited was rainy, hence not much blue sky.