Park at this Jurong East multi-storey carpark in the evening and you might hear a musical chorus coming from the roof.
"Lenggang, lenggang kangkung, kangkung di tepi paya," the voices sing in unison.
These are lyrics from the folk song Lenggang Kangkong (Malay for "swaying water spinach").
It is apt because every evening, 20-odd volunteer gardeners gather on the roof of Block 375A Jurong East Street 32 to weed, water and prune a large variety of plants.
"We're a very fun and crazy bunch," says Madam Kamisah Atan, their de facto leader and one of the first to work on the community garden.
Known as Sky Garden @ Jurong Central, it now has more than 60 volunteers, a far cry from the four gardeners who worked on it when it first took shape in 2004.
They come from all walks of life - there are executives, teachers, engineers, cleaners, retirees and housewives.
Many of the volunteers are residents who live in neighbouring blocks meant for low-income families, and are on financial assistance schemes.
It is hard work and volunteers often have to put in many hours to take care of some 60 types of plants that produce fruits, vegetables and ornamental flowers.
Madam Kamisah, who lives in Bukit Panjang, even takes an hour-long bus ride to the garden every day.
"Gardening is just one part of what we do.
"We also have tea sessions, bonding activities and potlucks after the work is done.
"It's a big, diverse group, with people from ages seven to 86.
It doesn't matter where you come from, you are welcome as long as you have the passion for gardening like the rest of us," says Madam Kamisah.
For the non-Singaporeans in the group, working at the Sky Garden allows them to bond with others in the community too.
Indian national Shilpa Sathe, 27, says: "Generally, the atmosphere in the garden is very relaxed and there is much chit-chat and laughter.
"We have people speaking Malay, English and Mandarin who bond with each other effortlessly despite not knowing the language sometimes."
The research associate at the National University of Singapore first came to Singapore two years ago and experienced culture shock.
But the people at Sky Garden helped her to integrate into the culture and learn more about living here.
She says: "Some members generously bring food and drinks and we exchange everything from recipes to health advice.
"More importantly, I get to speak to a lot of older Singaporeans who have interesting stories to share, and whom I would not have otherwise met through my own circle of friends."
Madam Grace Zhang, a Chinese national, says she decided to join the group because she enjoys mingling with the community.
"Rather than just growing my own plants at home, I like the idea of gardening alongside others.
It is literally helping out the grassroots," says the retiree, in her 50s, with a laugh.
With so many types of vegetables and fruits, harvest day comes at least once every month.
It's quite an affair, say Madam Kamisah, as many people turn up to collect the fruits of their labour.
She rattles off the list of produce they have successfully grown: "We have figs, Brazilian longans, rose apples, miracle berries, custard apples... When it's harvest time, everyone will know."
The foodies in the group chip in by preparing dishes using the produce, throwing a feast at the rooftop in the evening on the day of the harvest.
Says Madam Sathe: "While harvests are fun, the most exciting time is when I cook with all these delicious fruits and vegetables because it's that taste that validates all the work.
"No grocery store produce can taste as good and you develop a new appreciation of food when you produce it yourself."
This article was first published on Feb 22, 2015.
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