Dougherty's structure is just one part of the Minnesota Landscape Arboretum's summer exhibition "Powerhouse Plants," designed to show the role of plants in sparking creativity, stimulating health and providing renewable energy. Other components of the June 5-Oct. 10 program:

Veggies by the Yard: Five easy-to-copy vegetable gardens designed by the arboretum staff.

Gardener-Is-In: Visitors may harvest and tally seasonal vegetables, 9:30-11 a.m. each Sat., June 5-Sept. 25.

Chef's Row: Recipes by 10 top Minnesota chefs and growers, each featuring a favorite plant shown in demonstration gardens. Recipes will be online at the arboretum site.

Gardens of Eatin': Vegetables and flowers mixed in a demonstration garden plot.

Amazing Art: Five juried artworks about people and plants.

Specialty gardens: Demonstrations of organic and sustainable farming methods, solar cultivation with a seasonal sundial, treasure hunt, multifunctional wheat meadow, vertical garden, bio-energy exhibit.

MARY ABBE