Urban rooftop organic farming all-win solution for Hong Kong

Green roofs have once again hit the headlines when the government announced on Wednesday that no one will be prosecuted for the City University of Hong Kong (CityU) roof collapse last year. Safety was the key concern but this incident also prompted questions about the benefit of green roofs. The collapsed CityU roof was essentially a carpet of vegetation that very few people had a … Continue reading Urban rooftop organic farming all-win solution for Hong Kong

Real Environmental & Social Responsibility at Bijas

Environmental Social and Governance (ESG) is the term used by many corporations and the HKEX to describe what was previously known as Corporate Social Responsibility (CSR). Despite the change in name, its primary function is still public relations. ESG/CSR departments hold events such as beach cleanups, environmental forums, student sustainability challenges, visits to elderly homes, collecting “lai see” packets for re-use and so forth. The … Continue reading Real Environmental & Social Responsibility at Bijas

A Students Open Letter

  NOTE This open letter is re-published with permission from the environmental action group Grebbish. —————————- Let your action match your words! Potato@結束一桶專棄 I am a university student participating in a competition called ‘Glocal Greenovation’. The competition is a corporate social responsibility event hosted by Sasa and VolTra, and it is supported by twenty-five organisations and companies, including the Environment Bureau, and Google. The competition was … Continue reading A Students Open Letter

Soil Matters!


In Hong Kong, it’s easy to forgive the impression that we have transitioned to a post-soil society, where with enough concrete and wifi all of our needs can be met. We aren’t there yet and never will be, as soil is an irresistibly efficient way of providing nutrients for food crops to grow. It is the most valuable asset of a farm. Before we get the chance to finally appreciate soil, it may soon disappear. Agronomists predict that within 60 years global soil systems will be irreparably degraded.

Soil is a simple word that describes a complex ecosystem consisting of five essential components. Much of soil is a combination of minerals essential for plant health. Organic matter is made up of plant and animal remains that have been broken down by microorganisms, such as fungi and bacteria. Microorganisms are nature’s diligent nutrient recyclers. Soil needs to be loose to allow gases (oxygen, carbon dioxide) that are essential to the life processes of microorganisms and roots to circulate. Finally, water dissolves and transports nutrients to plant roots. Ideally, all five components are present in relative abundance. Soil composition and quality can vary widely, which is why organic farmers add compost and organic fertilisers to soil.

It may be tempting to grow crops without soil by using water-based hydroponic systems. These systems however have significant drawbacks. First, they can only provide for a fraction of our food needs. They are unable to grow large quantities grain such as rice, wheat, soya and corn that account for 60% of our diet (much of this is fed to the animals we eat). Second, they are capital and energy intensive, making them uneconomical except in circumstances where there is an abundance of both and a shortage of arable land (such as the Middle East). Continue reading “Soil Matters!”

Hydroponics and Property Development


July 2014. A Hydroponic facility under construction near Hok Tau. Turning green into desert.  

Hydroponic systems are touted by their promoters for safety and high yield. They claim hydroponically grown produce is safe from pollution because the vegetables are entirely detached from the ground. They also claim to be free of pesticides because hydroponic systems are usually housed in enclosed structures that keep pests out. According to it’s proponents, the high yield makes it suitable for a space-deprived Hong Kong.

Agriculture is an industry that exists within our economic system. As such, the laws of economics must apply to it. The law of comparative advantage, familiar to any first year economics student, states that we should specialise in areas where we have an advantage and trade with others for goods in areas where we do not. Both parties to the trade will end up better off.

Large-scale hydroponic systems were developed by the US military in the 1950’s to supply fresh vegetables to soldiers stationed on remote islands. The remoteness of the islands made the transport of fresh food costly and difficult. The barren soil made it unsuitable for growing on the land. Hydroponic facilities are factories that can produce “safe” vegetables anywhere, irregardless of the surrounding environment.

If hydroponic factories are completely safe because they are detached from the land then it doesn’t matter where they are located. The only requirements are land, labor and sources of water and electricity. Land, labor and water are significantly cheaper one hour away, in Shenzhen. If land and labor in Shenzhen are 1/3 to 1/4 the cost of that in Hong Kong, then a hydroponic facility in Hong Kong would be at a huge comparative disadvantage. The same “safe” vegetables could be produced in Shenzhen at a fraction of the cost. (It is for this reason, the law of comparative advantage, that all clothing factories have long since moved from Hong Kong to China.)

Since any first year economics student could arrive at this conclusion, might there be another reason why savvy businessmen (the owner of the facility in the photo above is the former CEO of Esprit, whose clothing factories are located in China) and highly educated bureaucrats are furiously promoting hydroponics? Continue reading “Hydroponics and Property Development”