This place is good not only for nice long walks in a mini-forest not far from Yerevan’s center, but also for witnessing a Soviet-era greenhouse. The botanical garden’s collection includes around 200 species of endemic, rare and declining plants. There are some greenhouses which are open to the public, so you can see the variety of plants grown inside the garden. I’ve even noticed price tags on some plants, which means you can buy them, if you know for sure that you can take them on airplane of course :).
Some of the additional sights you may encounter here are marrying couples having photo-sessions in the garden or school children having a study visit. Some families prefer relaxing here as well and having mini picnics. While this can leave some marks in the form of napkins or plastic bags or paper cups under the trees, there is an effort to keep the botanical garden clean, therefore your walk won’t be disturbed by similar sights (at least not often). It is indeed worth visiting this place for calming your senses and thoughts.
Update: the main greenhouse (seen in the pic) which was abandoned for years, has been upgraded and is open since spring 2021 for visitors. It is now an eco-educational center with the preserved structure designed in Soviet times.