14-year-old Jia Mingxuan used plastic bottles and steel tubes to build a device for young trees; it won gold at a German invention exhibition |
In northern China, newly planted trees can face a difficult start, with dry conditions and strong winds making it hard for young roots to get enough moisture. For 14-year-old Jia Mingxuan, the problem was close to home in Aohan Banner, where decades of work have transformed once sandy land into a greener landscape. A simple observation in his family kitchen gave him an idea: use the natural process of condensation to collect moisture from air and direct it towards a sapling’s roots. Built with steel tubes and recycled plastic bottles, his homemade device later travelled far beyond his hometown, earning an unexpected gold medal at an international invention exhibition in Germany.
How 14-year-old Jia Mingxuan turned Aohan’s dry climate into an invention idea
Jia grew up in Aohan Banner, an area that has undergone decades of efforts to control desertification and restore tree cover. His grandfather was involved in planting trees around the family home, giving the teenager a close view of how much the landscape had changed. According to Xinhua, the area had once been far more exposed to sand. Annual rainfall is around 380 millimetres, while the county is now reported to have forest cover across about 40.6% of its area, equivalent to roughly 373,000 hectares.The transformation has not removed the difficulties faced by newly planted trees. Saplings placed in exposed areas still need water while their root systems are developing. Getting that water to remote planting sites can require considerable time and labour.Jia became interested in that particular stage of the process. Rather than trying to create another irrigation system, he started thinking about whether moisture already present in the air could be put to use.
PC: Xinhua
The condensation principle behind Jia’s drought-fighting tree device
The starting point came during an ordinary evening at home. Jia noticed droplets forming where steam had condensed on a tiled kitchen wall. He remembered a physics lesson about condensation and began considering whether a similar process could happen underground around a tree.The idea became the subject of a school invention project in March 2025, when his science teacher asked pupils to develop their own ideas. Jia began drawing plans for a device that could gather water vapour and move the resulting moisture towards the root area of a sapling.His design relies on differences in temperature between the soil surface and deeper ground. Air is drawn through a steel pipe, while a cap at the top helps air circulate through the structure. As moisture in the air encounters cooler conditions underground, some of the water vapour condenses into droplets. Those droplets then move into the surrounding soil rather than being collected in a conventional tank.
Long journeys and 4am checks shape Jia’s sapling watering prototype
Jia boards at school and had to travel about 30 kilometres to his family home to test his prototypes, according to Xinhua. Testing the invention therefore meant making the journey back and forth rather than carrying out every experiment on campus.At one point, the prototype was buried about two metres underground. Jia sometimes woke up at around 4 am so he could return home, uncover part of the installation and check the moisture readings before travelling back to school. The materials were deliberately uncomplicated. Steel tubing formed the main structure, while recycled plastic bottles were incorporated into the homemade apparatus.There was no elaborate laboratory set-up behind the early experiments. The device developed through repeated testing in the conditions it was intended to address. That local focus later became part of what attracted attention at the international competition.
A simple sapling device competes alongside surgical robots and brain technology
Jia took the invention to the 2025 junior competition at iENA in Nuremberg, where more than 540 inventions by young innovators from different countries were presented. The range of projects was far removed from Jia’s basic planting device. Other entries included technologies such as surgical robots and brain-computer interface systems.For Jia, who had never travelled abroad before, the competition itself was unfamiliar territory. He reportedly wondered whether his rough-looking invention could compete alongside projects that appeared much more technically advanced. The result came as the awards were announced.After the bronze and silver medals were presented without his name being called, Jia believed his opportunity had passed. His invention was then announced as a gold medal winner.Reportedly, Oliver Mayer, chairman of the international jury, said the panel was impressed by both the teenager and the practical nature of his project. Jia collected the medal wearing a traditional Mongolian robe.
Northern China’s wider greening effort shapes Jia’s focus on young trees
The invention sits within a much larger effort to restore vegetation across northern China. Aohan Banner forms part of the Three-North Shelterbelt Forest Program, a vast afforestation programme covering parts of northern, northeastern and northwestern China. The work has altered areas that were once heavily affected by wind erosion and shifting sand.The county has also begun combining ecological work with newer technology. Photovoltaic projects have been used alongside sand-control measures, while digital monitoring and precision planting have become part of forestry operations.In 2024, nearly 80% of new planting in Aohan Banner was reported to have been managed using digital precision methods. For a teenager growing up in the area, the contrast between the older, labour-intensive approach and newer technology was difficult to miss.
A low-cost idea aims to support saplings where regular watering is difficult
Planting a tree does not guarantee that it will establish successfully. In dry and windy terrain, a young sapling can struggle before its roots have developed far enough to access sufficient moisture. Manual watering can address the problem, but repeated trips to distant planting sites are difficult to maintain across large areas. Jia’s apparatus was conceived around that limitation. Instead of requiring an external water supply, it attempts to use atmospheric moisture and natural temperature differences to provide small amounts of water directly around the root zone.The concept is not presented as a replacement for large-scale irrigation. Its purpose is narrower: to create a low-cost mechanism that could support young trees where conventional watering is inconvenient.
Jia’s simple invention now faces the challenge of working at field scale
The gold medal has attracted interest from people involved in the region’s long-running desertification work. Chen Xuexun, who has spent 34 years working on desertification control, said that experience had shown the limits of relying on manpower alone. He described young inventors and new ideas as necessary for the next stage of the work.Aohan Banner has since developed into a demonstration area for technology-supported afforestation, with monitoring systems based on Beidou satellite technology and precision planting among the tools being used. Jia’s project is now being refined with help from a research team from Shanghai. The aim is to improve the device rather than simply leave it as a competition prototype.
