Girlguiding Staffordshire's contemporary design will be called Stick in Time, with messages from Rainbows, Brownies and Guides on their journey through the movement.
The Girlguiding garden is being supported by urban environment charity Landlife, which donated thousands of flower seeds in the uniform colours of red, yellow and blue.
The seeds have all been sewn in peat-free compost, made from household green waste, donated by Derbyshire based Vital Earth.
Designer and guide leader Carol Adams said garden centres and locals had donated flower pots, while scaffolding planks from building firms would form a boardwalk.
"The donations from these businesses and organisations mean we'll be creating a modern and sustainable garden showing a girl's journey through the guiding movement."
Other sponsors include Crown, supplying paint for the wooden message sticks, Johnson Tiles, providing tiles for mosaics, and Mobilane for an ivy hedge to surround the garden.
The RHS BBC Gardeners' World Show runs at the NEC from 16 June to 20 June 2010.
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