You don't necessarily have to head to the Botanic Gardens to experience greenery in Singapore (she isn't called the Garden City for nothing!), but it's a gem to explore just beside town if you can.
This was taken in April 2014, when a month-long drought followed by a few days of torrential rain seemed to give trees reason to do some beautiful mass flowering.
Weekday mornings are perfect for a peaceful stroll. Picnic baskets & the Botanic Gardens go hand in hand! If not, Food for Thought provides decent comfort food & an even better ambience amidst the lush greenery.
If you exit from the Tanglin Gate, you can continue your walk down to the Tanglin area - a stretch of quaint (if expensive) European-style shops & restaurants. If major retail therapy is what you have in mind, the (in)famous Orchard Road is further down.