The Garden Walk is held by volunteers at the National Library twice every month, on the first and third Saturdays, respectively. It's free of charge and starts at 4pm, all you need to do is show up at the information counter on the first floor and they'll let you know where to stand to wait.
The building itself isn't terribly difficult to find and only a short walk from the Bugis MRT station, so location shouldn't be a problem for anyone. However, watch the sky closely before you head out. The walk isn't covered at all and umbrellas are not provided, so if it does start pouring much of the walk will essentially be canceled, the guides will only point things out from inside the building. This was the problem on our trip, as we were lucky enough to have a storm begin only about 15 minutes before we were to head out.
We're going to be pretty honest here and say if you really have nothing to do it's worth the trip just for a day out, but you probably shouldn't go out of your way to make it. The volunteers are obviously very interested in what they're doing and very helpful, but don't expect to see many actually interesting plants or flowers, as most of what you will see can be found outside any government building in the Garden City.
The walk itself takes place both in and around the library building itself, as the 10th floor has a garden space open to the public. Unfortunately, this is an outdoor garden and is also not covered.
(eventually our party decided to brave the rain)
Though the tour guide was very knowledgeable, we ended up getting bored after only a little while and wandering around to take some photos ourselves. Many of the plants were interesting enough, but we were disappointed at the lack of flowers.
(sour orange tree)
(banana plant, though there was only one tiny little pre-banana about an inch long)
(swiss cheese plant! this one was very cool, there are natural holes in the leaves!)
(we're not sure what this one is called, but the dual colored leaves were quite pretty)
After we finished doing the rounds on the upper floor we spent a little while exploring the plants outside the building, but overall there weren't many as interesting as those higher up.
(except this one, which somehow looks like each section should be a different plant)
(the prettiest plant of the whole tour was a potted orchid in the lobby)
Overall, we're glad to have made the trip to see the National Library building if nothing else, but it's probably not something we'd bother taking our friends or family to. The tours run pretty frequently so if you're at a loss for how to spend an hour and a half of your Saturday by all means go for the tour- just don't forget your umbrella.
(pris was pretty excited to put her photography skills to work though)