KEY POINTS:
A small balcony in one of Hong Kong's high-rise gardens boasts branches laden with lemon and lychees, although it would seem there are few more unlikely places for a fruit tree to thrive than 30 storeys off the ground.
Meanwhile, in crowded public housing estates in Singapore, cucumbers and lettuces are growing in rough wooden boxes in concrete yards under fluorescent light.
And Chinese schoolchildren enjoy an afternoon with their parents not far from the Great Wall near Beijing, planting some of the millions of trees keeping the desert at bay and making the air easier to breathe.
Asia's green-fingered enthusiasts are leading a revolution that sets out to combat CO2 emissions, provide a bit of colour, and bring the scent of flowers in people's lives.
Whether it's huge state-sponsored tree-planting programmes in China or small roof-top gardens and balcony bonsais in Hong Kong and Singapore, gardeners across Asia are taking up their trowels and digging for what could be an environmental revolution.
Hong Kong exemplifies the rise of the tower block in Asia, in which the green-covered mountainsides of the island and the relatively undeveloped parts of Kowloon gave way in the 1950s and 1960s to low-rise, then high-rise residences.
A surgeon called Arthur van Langenberg has become the brave champion of urban gardening - on a quest to show that living in Hong Kong does not mean abandoning your connection to nature.
A Hong Kong native, he was surprised to discover there was no manual on how to garden in this still-green former colony, so in 1983 he published Urban Gardening for Hong Kong.
He began with "flower pots on window sills, wooden packing crates in verandas, dragon urns at entrances, eventually graduating to a small garden" and now has avocado, papaya and lemon trees growing in the concrete yard of his apartment near the city centre.
Singapore's dizzying pace of growth means a shortage of gardens, largely because four-fifths of Singapore's 4.5 million people live in high-rise tower blocks.
But Singaporean Wilson Wong has started the Green Culture website, which provides information for local horticulturalists. The website forum has attracted more than 1500 high-rise gardeners, and last month Singapore unveiled Treelodge@Punggol, its first "green" housing estate.
Plants growing on the walls keep the 712 apartments inside the seven, 16-storey tower blocks cool.
On top is an eco-deck, a large garden with a jogging track and exercise stations for seniors. The development is the biggest green residential project in Singapore to date.
In China, the world's most-populous nation, people are also getting on to their roofs, to grow vegetables, flowers and small trees.
Beijing has pledged to add 100,000 square metres of roof gardens every year from now until 2010, and the country is taking to horticulture in true revolutionary fashion.
It is dispatching a Green Long March which will wend its way across China next month to underline its commitment to environmental sustainability.
Given the success of the previous Long March, perhaps the current march, led by horticulturalists, could bring about a similar green revolution.
- Independent