Thousands of miniature plants will be used to bring colour and life to the decorative set pieces in this year's edition of Dahlia Dreams at Gardens by the Bay, which opens next Friday.

For example, a 5m-tall medallion of the Chinese word fu, which means blessing, showcases deep red kalanchoe blossoms against a striking background of yellow pansies.

A pair of golden rats will be made up of sedum and begonia plants, though they are now green as the flowers have not blossomed yet.

The plantlets are cultivated separately in trays before they are embedded into the layer of planting media carpeting the structures.

The small plants, which will continue to grow on the structures, take in water from automatic irrigation systems and must be trimmed continually.

It will be the first time this form of horticultural art, known as mosaiculture, is displayed at the Flower Dome.

The display is a collaboration between Gardens by the Bay and Chinese landscaping and floral design company Beijing Florascape, which specialises in mosaiculture and has showcased its works at major Chinese events such as the 2008 Summer Olympics.

The mosaiculture pieces will include a pair of lucky golden rats, a 7m-tall traditional archway and various zodiac animals.

A total of five plant varieties will be used on them.

"We have to choose species that have vibrant colours, yet grow slowly and are relatively easy to groom," said Beijing Florascape's project manager Yu Yanyan, 39.

As the display depends on how well the plants flourish, Beijing Florascape sent a test batch of plantlets to Singapore last year so the team could pick the ones which thrived in a tropical climate.

Some plants were also hybridised so they can bloom earlier, or for a longer period of time, to coincide with the six weeks of the Dahlia Dreams display.

Surrounding the mosaiculture pieces will be other festive flowers, such as peach blossoms, azaleas and pussy willows.

Throughout the display period, more than 70 varieties of dahlia flowers will also be featured, including the 25cm-wide "dinner plate" dahlias.

Around 90 people from both Gardens by the Bay and Beijing Florascape have been involved in the preparations, which began more than a year ago in 2018.

"We just want our visitors to be able to experience something new each year," said Mr Gary Chua, 50, deputy director of conservatory operations at Gardens by the Bay.

He added that working with Beijing Florascape is a good opportunity to showcase traditional Chinese culture.

The two golden rats, for example, stand in a field of wheat celosia flowers instead of their more common counterpart, the feather celosia.

This choice was inspired by the ancient belief that having rats in a household symbolised wealth, as it meant there was extra food in the barn for rodents to steal.

The Chinese character fu on the mosaiculture medallion is specially fashioned after the handwriting of Emperor Kangxi (1654-1722) of the Qing dynasty.

It contains the glyphs of other auspicious characters, including zi (descendants), cai (talent), tian (farmland) and shou (longevity).