I'm not sure how much it costs to visit as my ticket was paid for in advance, but I will say I enjoyed what I saw. The outdoor gardens offer a fairly simple path to go from one area to the next. The Japanese gardens were quite boring but the rest are nice to view. I'd say the Waterfall area was my favorite.
The glasshouse is a much better area. The plants have more color and the many butterflies flying around make for great photos. Make sure to go all the way up to the top to get a good view.