The Mayor of Southwark Cllr Sunil Chopra and Rosie Boycott, chair of the London Food Board, were among the VIP guests who came to see the dozen young traders in action.
Chef Marcus Verberne from the market's Roast restaurant also dropped in to buy some local rhubarb.
Proceeds from the sale will be donated to the FareShare charity for its work tackling food waste.
The summer sale was the culmination of a partnership between Borough Market andáthe School Food Matters charity.
With the help of funding fromáUnited St Saviour's Charity, the programme started back in the spring when pupils were given training by Blue Peter gardeneráChris Collins.
They were also taught some top trading techniques by market staff and traders.
"Our budding young gardeners have been working very hard tending their crops and learning exactly how food goes from seed, to marketplace, to plate," said Keith Davis, managing director of Borough Market.
• There is another opportunity to buy ultra-local produce at Borough Market on Saturday 19 July when gardeners from the Edible Bankside project sell their fruit and vegetables grown within a mile of the market.
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