I visited this WHS in June 2013. The ironwork is still intact and well preserved. Obviously this is just the cherry on the cake, since Kew Gardens are world famous for the collection of plants and flowers. My personal favourites were the lily pads and the carnivorous pitcher plants. The cacti were very interesting but I felt that the cacti in YSL's Majorelle Gardens in Marrakech were better kept. Only negative point about this WHS is that it is en route to Heathrow which means that every minute 2-3 planes fly over it. Very annoying if you like peace and quiet ... bring your earphones and listen to some music and it'll do the trick :)