Three designers will receive a £5,000 grant to build a 25sq m garden and display it at this year's BBC Gardeners' World Live 2010 at the NEC Birmingham.
Competition entrants must create an innovative and modern garden, with space for growing fruit and vegetables, focusing on sustainability, good environmental practices, diversity and recycling.
Budding designers must supply their drawings with a list of the plants to be featured by 22 January.
NS&I Grow Your Own representative Garry Bond said: "This competition combines creativity in horticulture with growing your own produce, and each year both professional and aspiring gardeners enter for a chance to showcase their design at the garden show. And having seen past winners go on to forge successful garden design careers, we hope this opportunity will enable more people to explore the exciting world of gardening and horticulture."
Application forms and terms and conditions can be downloaded from the NS&I website at www.nsandi.com/rhs. Winning entrants will be notified by 29 January. The competition is in association with the Royal Horticultural Society.
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