Gumtree is South Africa's largest classifieds site, with 20 ads posted every minute and over 700 000 live ads to choose from at any time. Mediamark, working with its creative division Lab42 and regional radio station Jacaranda FM, proposed “Secret Stash” - a mystery box concept that had people buzzing for weeks in face-to-face communication, on the airwaves and on social media.

Secret Stash saw South Africans trying to guess what was locked in a mysterious freight container suspended from a crane parked at busy locations around Jacaranda FM’s catchment area. Once consumers were intrigued by the secrets of the box, Jacaranda FM and Gumtree owned up to the stunt. They invited Jacaranda listeners to phone in and guess what was inside the box - but to enter the competition, they had to place a listing on Gumtree.

Says Richard Taylor, head of Lab42: “We’re often told to think outside the box when brainstorming a campaign to come up with creative concepts that deliver results that outperform the benchmark. But we think it can be much more effective to look inside the box, evaluate your assets, and combine them in smart and original ways.”

An arsenal of assets

Mediamark started by looking at which of its assets could help Gumtree meet its goals. These included the award-wining creative division, Lab42; advertising inventory for Jacaranda FM with its more than two million listeners; online and mobile reach; and an on-the-ground events division.

Taylor says: “With these multiple platforms, we had a number of angles from which we could approach the challenge of keeping consumers captivated throughout the weeks of the campaign. These included social media channels such as Facebook and Twitter; display advertising on Jacaranda FM’s website; content on Lekker TV, a Jacaranda music show on DStv’s Kyknet Musiek; and prominent outdoor billboards.” Die Heuwels Fantasties endorsed the competition by giving away a guitar on Gumtree.

Boiling point: an on-the-ground activation

The hype peaked with an event sub-sponsorship of BP Jacaranda Day, where the regional radio station hosted some of South Africa’s hottest musical talent at Supersport Park in Centurion. With more than 15 000 people in the crowd, one lucky listener was named as the winner of everything inside the container, including a brand new car from fellow sub-sponsor Volkswagen.

“From on air and in the air to on-the-ground and social media, this campaign drove record engagement for our client,” says Warren Bedil, business development director at Mediamark. “It is a strong showcase for the power of multichannel campaigns in amplifying a message, increasing its impact, and extending its reach, all helping an advertiser to maximise return on investment and meet its business objectives.”

The customer experience

“The campaign delivered over 4000 listings and 2000 app downloads – four times as many as any regional or national radio campaign we’ve run in the past,” says Claire Cobbledick, marketing manager at Gumtree. “We were blown away by the entire campaign from planning to execution, and enjoyed the way that the collaboration between ourselves, Mediamark and Jacaranda FM helped to bring our message to life.”

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