If you are fans of orchids, there is a 1'000 m2 building with 3 hothouses and 2'000 species of orchids and associated tropical plants just across the road from the CH national museum in Prangins Vaud ( https://www.chateaudeprangins.ch/en ).
It is called Orchidarium ( http://orchidarium.ch/ ). The website is only in FR. The opening times are listed.
They have one hothouse that has the plants that are ready for sale (these are premium products with associated prices compared to Aldi etc.). And there are 2 hothouses that they use for growing/flowering etc. their stock that is imported from the main producing countries.
They also have decoration items for plants and the house.