The harvesting of seaweed isn’t new but, in Australia, the actual cultivation of seaweed for culinary purposes is a relatively recent development. The first land-based seaweed farm began operating in the Shoalhaven region of New South Wales in 2013, founded by a marine ecologist from the University of Wollongong, Dr Pia Winberg. Winberg’s company, PhycoHealth, continues to supply seaweed products for food, supplements and beauty products.
The history of seaweed consumption in Australia is a long one. Researchers have found evidence that Indigenous Australians ate a range of seaweed species, including bull kelp which the Tasmanians prepared by drying, roasting, then prolonged soaking. Seaweed as a food was neglected by early colonists, however. It wasn’t until the early 20th century that articles began to appear describing the potential nutritional and economic benefits.
In 1910, a number of newspapers published a short article about a seaweed farm in Cornwall. Rather than cultivation, this method of “farming” consisted purely of gathering what was deposited on beaches by stormy seas.
On the British coasts alone, 400,000 tons of this weed are collected each year. It is a form of labour with peculiar attractions for the easy-going type of individual, for the management of a farm of this description entails no back-acheing toil, requires no capital to speak of, and the stormy elements themselves see to it that the “crop” is deposited at the very feet of the “farmer” – a profitable industry within the reach of the very humblest.
Another article, in 1911, described the methods used in a Japanese seaweed farm and gave details of the many culinary and other uses of seaweed in that country. The writer claimed millions could be made from an Australian seaweed industry.
Five years later, Frank Farnell wrote an article for The Sun titled Farming the Sea – A new industry for Australia. Farnell was a public servant and former politician who had been, for several years, chairman of the Fisheries Board. His article referred to news that members of the Earnest Shackleton expedition to Antarctica had survived months of isolation by supplementing their diet with seaweed. “I feel certain,” he wrote, “that with a thorough investigation of this source of latent wealth in Australian waters it will be discovered that our country neither lacks in varieties nor supplies what form the basis for successful industries in, say, Japan. In that country a distinctive feature is the use made of marine vegetable growths.” Farnell also mentioned the use of “marine vegetation” in America, Scotland and Ireland.
Through the 1920s and 1930s, there were occasional mentions of seaweed farming overseas, including “mariculture” on the Californian coast. A 1935 article describing the harvest of seaweed in the Channel Islands describes several culinary uses in Britain.
One kind of edible seaweed, much esteemed by both the Irish and Scotch fishermen, is grilled by being rolled over a red hot poker. Another variety is stewed with hot milk into a sort of blancmange, while the Wales small, flat cakes, known locally as “sowle bread,” are made from yet another kind.
By 1941, the CSIRO was investigating the commercial harvest of seaweed for the production of agar agar, a gelling agent used in meat canning, confectionery and in bacteriological science. In the post-WWII era, demand for agar agar increased, as Japan had previously produced some 95 per cent of the world’s supply. A New South Wales firm obtained a permit to create a seaweed farm on the Clarence River in the state’s north. However, there’s no indication that the venture went ahead or, if it did, was successful.
In the 1950s, harvesting of kelp began on King Island in Bass Strait, where a local kelp industry continues today. The King Island industry (along with many other seaweed ventures) depends on storm-cast weed. Several factors, including ocean warming, have threatened the continuing viability of kelp forests, so living kelp can no longer be harvested from the ocean.
Revived interest in seaweed farming over the decade to 2023 has been driven by a number of factors. Among them is the capacity of marine vegetation to sequester carbon, helping to mitigate the effects of climate change. In addition, a supplement made from certain seaweeds has been shown to reduce methane emissions from livestock. A venture called Sea Forest, based in Tasmania, is growing a species known as Asparagopsis armata, a red algae, with this in mind. The influential Danish chef René Redzepi also ignited foodies’ interest in foraging, with seaweed featuring on his Instagram page.
In 2020, the commercial cultivation of several kelp species began, in ocean-based farms developed in association with the Atlantic salmon farms operated by the Tassal Group. There are now a number of peak bodies representing the industry, including the Australian Sustainable Seaweed Alliance and the Australian Seaweed Institute. The industry “blueprint” developed by the Institute for Agrifutures can be found here.