Jamie's Farm, set in Waterloo, combines all aspects of farm life from planting and rearing animals to cooking and organic waste recycling using fish.
Oasis Trust is one of the partners running the programme. Steve Chalk is founder, he told Premier he was walking past one day when he decided that something should be done with the land.
They were given it, working with St Thomas' hospital, to develop an inner-city farm, which they would like to make the best in Europe.
He said it is a really important project for the children: "Most of the children at our schools, in this community, they don't so much as have a window box, let alone a garden.
"To come here is fantastic, but then farming and horticulture is integrated into our curriculum, so they're going to learn about growing, food, animal supply chains."
He added that they had been contacted: "The Duchess contacted us and asked to come see this, so that's a wonderful thing.
"I'm sure she's been on larger farms, but probably never quite an excited farm as this one."
Jake Curtis, Programme Manager of Jamie's Farm told Premier that his farm outside of London has had a massive impact on the lives of young people: "Over half the young people, who come to us at risk of exclusion, are no longer in that category six weeks on, which is a really profound difference.
"We're keeping them in school, we're keeping them engaged in education, and we're allowing them to really transform their approach to working with adults in the future."
He said there is a whole range of challenges children have the opportunity to take on and learn from: "We have farming - in the sense that we have small scale jobs that really allow young people to get sense of achievement, from tackling their challenges and looking after the animals.
"We have a family environment, which offers them this nurturing, supportive space, so that they can overcome some the challenges that have held them back so far.
"And then we have the therapeutic provision, where our trained councillors and therapists are able to discuss with young people the challenges that they're experiencing in their day-to-day lives."
Camilla helped garden with the children, she planted a special rose:
Listen to Premier's Hannah Tooley speak to Oasis Founder Steve Chalke here:
Listen to Premier's Hannah Tooley speak to Jake Curtis here:
Chickens, sheep and pigs can be found at the farm:
Children from one of the local schools performed for the Duchess:
