Kate Middleton shared a sweet tribute to Prince William on Blue Peter – did you spot it?

It almost went unnoticed

The Duchess of Cambridge paid a special to her husband Prince William during her appearance on Blue Peter – and it almost went unnoticed! Kate joined a group of children to launch a once-in-a-lifetime competition and have fun at Westminster City Council’s Paddington Recreation Ground, trying her hand at activities including pond dipping, planting and team den building.

During the group’s second activity, Kate and the children upcycled old household items and wellies into plant pots, with the Duchess opting to plant a Dianthus Barbatus into a silver watering can. The colourful pink and white bloom is better known as a Sweet William – a sweet nod to the Duke of Cambridge.

The Duchess of Cambridge planted Sweet William flowers on Blue Peter

The Duchess joined forces with Blue Peter to launch a new competition as part of her mission to encourage children and families to get back to nature. The competition asks viewers to design a sculpture for her Back to Nature garden when it arrives at RHS Wisley in September.

GALLERY: See George, Charlotte and Louis in Kate's Chelsea Flower Show garden

Speaking about encouraging people to enjoy nature more, Kate told presenter Lindsey: "It encourages creativity, confidence and even a short amount of time - 10-15 minutes outside - makes a huge difference to physical well-being but also to our mental well-being."

The Duchess has launched a competition on the children's TV show

Kate has a passion for gardening and spending time outdoors, and recently showcased her incredible Back to Nature garden at the Chelsea Flower Show. The garden proved a hit with members of the public and the royals alike, including William and Kate’s three children – Prince George, Princess Charlotte, and Prince Louis – who were given a special preview before it opened to the public.

MORE: How to recreate Kate's Chelsea Flower Show garden

The children all helped to collect moss, leaves and twigs to decorate the garden, while Hazel sticks collected by the family were used to make the garden’s den, proving how important it was to Kate to let her family have a special role in the project.

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