What we liked best about Jardin Botanique de Montreal is that it was nicely organized by theme or type of plant. My favorites were the edible plants and the Japanese Gardens. I was also a big fan of the houses such as the insect house and a conservatory.
The conservatory in particular (and it might actually be called something else) had informative videos and interactive exhibits that taught me about pollution, suffering wildlife species, and the environment. I could have stayed there a lot longer than I did!
There were nice paths and plenty of places to relax. I would have preferred better descriptions of the plants or sections. There were only signs with the name of the plants but no additional detail.
There were also roads and grassy expanses that seemed incongruous with the rest of the botanical gardens. Something about that seemed incomplete.