The Tashkent Zoo mostly resembles a kids entertainment park, plus animals. Lots of buzzing scooters, shooting ranges, 7D cinemas etc. Good if you brought kids. If not, it’s still perhaps the cheapest place in the world to look at a giraffe, but the living quarters for animals are from the past century. The animal highlight are the 2 Siberian tigers.
The Botanical Garden on the other hand is very big and very wonderful. Wild and unmarked, unless you are a trained botanist you are mostly here to soak up the atmosphere. It’s not the reason why anyone comes to Uzbekistan, but if you like gardens, plants, peace and solitude, you will enjoy this one.