The Old Manor House Garden and the relaunched National Gardening Centre are expected to draw 50,000 extra visitors in 2012 on top of Capel's usual 60,000 because they are so near the Olympic site.
Capel chief executive officer Steve Dowbiggin said: "The beauty of the gardens is that all the plants and products are available for consumers to buy in garden centres." He told the Queen that the 34 show gardens, sponsored by HW, at Capel were like those at the RHS Chelsea Flower Show but better because they were open every day of the year.
A top TV designer and two 2010 Chelsea gold winners now want to build gardens at Capel. Dowbiggin said sustainability issues meant more designers wanted to find a permanent home for show gardens or even solely to promote themselves at permanent shows.
Taylors Bulbs is in talks to build a year-round bulb garden. Redwood Stone built the Old Manor House Garden and plans two or three more phases, including a gatehouse and medieval kitchen garden, said owner Tim Redwood.
The Queen visited the John Woods Family Friendly Garden, reconstructed from the gold medal-winning Upwardly Mobile Garden at Chelsea. The nursery gave her majesty a Magnolia 'Black Tulip'.
She also received a presentation from Suttons Seeds and saw the Scotts Miracle-Gro Garden and the garden built by students to mark the Queen Mother's centenary.