With spring in the air, thoughts of many may well be turning to tackling the garden.

However, a group of householders in the Shetland town of Lerwick are instead being asked to give over a patch of their garden to help shine light on the past.

Archaeologists want to dig down into garden plots in the hope of finding centuries’ old household rubbish dating from a vibrant period when the Northern Isles were at the very centre of European trade.

They have asked people living in the historic centre of Lerwick to consider hosting an excavation in their garden, so they can sift through the soil in the hunt for old broken pottery, animal remains and any other clues to life in the town as it grew from a tiny community to bustling centre of trade.

It’s hoped that exploring a network of test pits in gardens at the heart of the oldest part of the town will not only help identify the diet of the early townsfolk, but also the range of goods and materials being imported to Shetland at a vibrant time in its history.

Archaeologists from the international Looking in from the Edge project have appealed for anyone with a garden, border or vegetable patch interested in helping, to get in touch.

Each test pit will measure just one metre square, and although the dig will be led by the research team, householders and locals are also being invited to take part if they want to.

Afterwards, the excavation patch will be carefully returned to how it was.

The Lerwick Garden Dig is part of the major international project which is examining the Northern Isles’ place in European trade networks of the 15th to 18th centuries.

Trade prospered in Shetland and Orkney during that time, with a flow of goods between cities in Germany, the Baltic states, Scandinavia, the Scottish mainland and Holland.

In exchange for cotton, clothes, foodstuffs, tobacco and ceramics, Shetlanders supplied trading partners with dried fish, knitwear, butter and cloth. In Orkney, barley was traded in large amounts.

The three-year international study involves researchers from the University of the Highlands and Islands Archaeology Institute and academics from Germany, Norway and England.

As well as looking at how trade impacted on the Northern Isles’ economies and sparked urban growth, the project hopes to unpick its influence on culture and the islanders’ lives as they hosted an influx of European traders and boats throughout busy summer months.

Prof. Mark Gardiner, Professor of Medieval Archaeology at the University of Lincoln, said even a small one metre pit in a Lerwick garden could throw up items which help build a picture of how the town developed as a lively centre for international trade.

He said: “The Northern Isles were sucked into this large trading network and far from being stuck out in the Atlantic, there is a great level of trade taking place.

“Merchants from places like Hamburg and Bremen would have become trusted members of the community. They’d arrive in summer and leave in winter and would have been known to the people of Shetland.

“There must have been a traffic of cultural exchange as well as trade.”

He said creating a series of test pits would help build up an understanding of how the town developed.

“We are really looking at people’s old rubbish,” he added. “There was no local council coming to take what they no longer needed to the tip, and what they threw out is a good indicator of what was being consumed and what they were using.”

Even small pieces of broken clay pipes can offer a tantalising clue as to life in the past, he added.

“If we find broken clay pipes, that implies there was tobacco. Pipes also often had maker’s marks and dates on them.

“So, while it may seem like rubbish, to us it’s a clue to what is going on.”

European trade was driven by the Hanseatic League, which originated in the 12th century and created links between German merchants and traders across northern Europe, Scandinavia and the Baltics.

Routes were tightly controlled and led to a vibrant exchange of goods between countries.

While that brought European trade to the Northern Isles, it ballooned in the 17th century when German and Dutch vessels became regular visitors, anchoring in Bressay Sound and bringing distinctive redware pottery, cotton, fishing nets, metal cooking pots and buttons.

In return, islanders offered woven cloth, knitted items – socks were particularly sought after – and butter.

The growth of trade led to homes springing up in rows stretching from the seashore and which laid the foundations for today’s town.

Prof. Gardiner added: “Boats were bringing in items that were not available in the Northern Isles, so there must have been marvelous excitement among islanders when they arrived.

“It meant that they were able to join this European market of goods and trade.”

Earlier test pit digs carried out by the project in rural areas of Shetland revealed shards of broken redware pottery, suggesting that trade was not confined to Lerwick, and that farmsteads were also involved.

The Looking in from the Edge project involves the University of the Highlands and Islands Archaeology Institute, the University of Lincoln and the German Maritime Museum, in Bremerhaven.

Funded by the Arts and Humanities Research Council and the German Research Council, a key element of the project is involving local communities and training volunteers in research methods from archaeology and history.

People who are able to offer their garden for the project are being asked to email enquiries.orca@uhi.ac.uk.