As I mentioned in a previous post, I went to the Center near the German city of Münster this last weekend. I got a few pictures of different things there to give a general idea of how big the place is, and what kinds of trees they have there.
They have a wide array of soils, soil mixtures, stands, pots etc. A room of about 40-50 sqaure meters of pots, ranging from pots for accent plants to special langcape pots the size of a coffee table. The also have a few concrete creations and differing stones for langscape or multple-tree constructions.
They also have a wide variety of plants with several gree houses, and gardens. I didn't have time to get into one of their main displays, where the most expensive trees are on display. (It was midday, and we had been traveling for a couple of days, and with the warmer, sunnier weather, I wanted to get home.)
I will add a few pictures in the replies.