See How Kate Middleton’s Garden Fits Into Her Plan to Help Kids Stay Healthy

As Kate Middleton unveiled her special show garden, she stepped up her campaign to get more children to spend time outdoors.

Her “Back to Nature” garden at the RHS Chelsea Flower show – where she was pictured enjoying the surroundings on a swing – features a bridge over a little stream and a wooden treehouse.

But behind it is a bigger plan: The garden forms part of the Duchess of Cambridge’s ongoing work on early childhood development and her mission to support efforts that give every child the best possible start in life.

“In recent years I have focussed much of my work on the early years, and how instrumental they are for outcomes later in life,” she said as her office released pictures of it Sunday. “I believe that spending time outdoors when we are young can play a role in laying the foundations for children to become happy, healthy adults.”

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It comes at the one-year anniversary since Kate and the Royal Foundation established a steering group of experts on the early years, to seek advice on what is needed to support all children. The group recently concluded its work and she has written to the members to thank them for their help.

“Through our work, you have reaffirmed my belief of just how timely it is to focus on what happens in the early years of life, and how pivotal a stage of life this is for a child’s future,” she told them.

Tackling the challenges facing children in their early years is Kate’s defining theme of her royal work. “I hope my long-term commitment to working in the early years will help make a difference over a generational timescale,” she adds. “Your thoughts and advice will continue to be hugely valuable as I shape my thinking for the years ahead.”

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The work is defining the princess’s royal work. One of the members of her committee, Peter Fonagy, from one of Princess Kate’s charities told PEOPLE recently, “She is personally committed. This is her career, and she wants to achieve and support it in all its different forms.”

The chief executive of the Anna Freud national Centre for Children and Families added, “The priorities will change over time. But to have someone in her position of leadership and convening power to lead that process — to myself and my successors — is a gift. It will make everyone’s job easier, as it has mine.”

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In her letter to the committee, Kate said it has ��been fascinating to explore the scientific research in this field and see just how clearly it all points to the same thing: that the first few years of life, from conception to five, are pivotal for our future health, happiness, and ability to cope with adversity – and probably more so than at any other point of our lifetime.”

In a visit last year, Kate heard some of the scientific work being done on understanding brain development.

“Understanding that our brain develops to 90% of its adult size within these first five years helps crystallize how our experiences in these earliest years are so impactful and influence who we become as individuals. What happens in our early years is vital to our being able to engage positively in school, work and society, and ultimately, to how we bring up our own children.”

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And speaking of the parents and carers and children she has met and heard about over the year, she said it “has been reaffirming and immensely heartening to hear from the parents and carers you work with about what they need, and what they want for the children in their care.”

She adds, “It was abundantly clear – universally – that regardless of location, demographic or circumstance, all parents share the wish for their children to grow up happy, healthy, and equipped to be able to take every opportunity that comes their way. It is heart-breaking to know that there is a long way to go to realising this wish.”