Spring is the time of year when Cotton Tree Drive – a busy road connecting Hong Kong Island’s Central business district with the upmarket Mid-Levels residential area – best illustrates how it got its name. The cotton trees ( Bombex ceiba ) that line the thoroughfare are one of a number of brightly flowering tree species highly visible at this time of year across Hong Kong. Conservation in Hong Kong: citizen scientists enlisted to record and safeguard city’s amazing biodiversity The native species, with its large, fleshy cup-shaped flowers that range in colour from bright crimson to a rich mustard, stands straight and stoic for most of the year, its branches often bare. In spring, the cotton tree bursts into bloom, and can be seen lining many streets and thoroughfares across Hong Kong. Some of the finest examples are a fixture of Hong Kong Park, where there are two individuals designated “old and valuable” by the government. Spectacular cotton trees can also be seen bordering Victoria Park, including three along King’s Road, which bloom in three distinct colour variations – red, orange and yellow. Another spring blossom is the abundant bauhinia, or orchid tree, of which there are a number of species, native and introduced. The best known is Bauhinia blakeana , a hybrid species whose purplish-pink flower was adopted as the regional emblem of Hong Kong after the 1997 handover of the territory from Britain to China. Bauhinia trees, members of the legume family, produce an abundance of flowers at this time of the year, and can be found everywhere from parks and roadsides to wilder environments. Cousins of the Hong Kong bauhinia include the camel’s foot tree ( Bauhinia variegata ), with its smaller, purple blooms, and the white bauhinia ( Bauhinia alba ). The flowers of these two varieties are not as large and stylised as the flower on the Hong Kong flag, but they share the same graceful five-petal formation. Ten of Hong Kong’s most endangered species, from animals hunted for TCM to the gigantic Plantasaurus A more exotic sight in spring is the vivid yellow flowers of the golden trumpet tree ( Tabebuia chrysantha ). A native of South America, and introduced widely in public parks and urban areas as recently as this millennium, these small, often sparsely leaved, trees are unmissable. Although each of the trees’ flowers resembles a trumpet, the blooms sprout in tight clusters. The golden trumpet is undoubtedly a favourite among Hong Kong’s urban landscape designers, given that they seem to have been planted in every park in the city. A rarer cousin of the golden trumpet tree can be seen at the junction of Wong Nai Chung Road and Broadwood Road – the rosy trumpet tree ( Tabebuia rosea ), which is just as glamorous, but bursts into flashy pink flowers in spring. A little less eye-catching are the city’s opulent mango trees ( Mangifera indica ). Typically dense, with a full, dark-green canopy, mango trees tend to blend into the background of the city’s urban landscape along with many broad-leaved species such as the candlenut tree ( Aleurites moluccanus ) and the white jade orchid tree ( Michelia x alba ). During the spring, mango trees become transformed into fiery orange domes. The blossoms themselves are tiny, but they sprout along tapered conical stems that on occasion cover the entire canopy of the tree. A small number of mature mango trees are currently in full bloom in Hong Kong Park. There are numerous other trees blooming during spring in Hong Kong. The tall bottlebrush tree ( Callistemon viminalis ), for example, with its long, slim, hanging branches and slender leaves, with row upon row of tiny, bright-red needlelike flowers. These blooms give the species, a native of Australia, its name, since they resemble the long brushes used to clean bottles and test-tubes. Biohackers: the DIY biologists out to barcode all Hong Kong’s plants, insects and animals Unlike the world renowned cherry blossoms of Japan, or the jacarandas of Sydney, Hong Kong’s blooming spring trees don’t attract the same sort of attention or local pride. But that is no reason not to get out and share in their celebration.