Unlike some of the more well-known gardens in the area (such as the gardens in Victoria), VanDusen is not very crowded at any time of year. Plus, there is a hedge maze, there is a ton of art, there is lots of educational information, and - of course - there are lots of awesome plants. The cafe (free to go to) is also beautiful/affordable.
Avoid the crowds at more popular gardens, and check out VanDusen! The hedge maze is a popular attraction, and children and adults alike enjoy the challenge. This is a walk through the park you will not regret paying for. There are also lots of events year-round (check the website for details).
Free parking is available on nearby residential streets. Mind the restrictions - they're strict.