January 31–May 10
Spring Flower Show
Garfield Park Conservatory
Chicago, Ill.
The Spring Flower Show highlights a changing selection of spring blooming plants. The first half of the show will feature azaleas; the later half, hydrangeas. In addition, the display will feature more than 5,000 bulbs, including tulips, daffodils, and hyacinths.

March 7–May 17
RARE: Imperiled Plants of Colorado
Denver Botanic Gardens
Denver, Colo.
This juried exhibit features 40 contemporary illustrations of Colorado rare plants by members of the Rocky Mountain Society of Botanical Artists. Designed to promote awareness and conservation of these special plants, the exhibit will travel the state in 2009 and 2010.

March 7–May 31
Spring Butterfly Exhibit
Desert Botanical Gardens
Phoenix, Ariz.
dbg.org
Butterflies fill the Marshall Butterfly Pavilion. Special displays feature butterfly hosts plants and up-close looks at butterflies. Coincides with the garden’s exhibit of the renowned artist Dale Chihuly’s blown glass sculptures.

April 25
More Green Per Drop Festival
Tucson Botanical Gardens
Tucson, Ariz.
Find out innovative ways to save money, protect the environment and maximize your water for a greener landscape or garden. Tree pruning workshops provided by Bartletts Tree Service in addition to a gray water and rain water harvesting workshops, succulent planter design demonstrations, irrigation design and much more.

April 4–May 10
Hanami: Celebrating the Cherry Blossom–Viewing Season
Brooklyn Botanic Garden
Brooklyn, N.Y.
During Hanami, the BBG’s world-renowned collection of flowering cherry trees take center stage. The celebration culminates in the two-day Sakura Matsuri Cherry Blossom Festival, which is May 2 and 3 this year. Saturdays and Sundays during Hanami, at 1 p.m., take a Seasonal Highlights Tour focusing on the ethereal beauty of cherry blossoms. The Zagat-rated Terrace Café will offer a selection of special Japanese entrées throughout the season, and the Garden Gift Shop will offer exquisite Hanami–related items. Track the cherry display using CherryWatch at the BBG’s website.

April 4–June 30
Light Gaps
Olbrich Botanical Gardens
The trees are trimmed and the bushes are pruned during annual maintenance in the Bolz Conservatory, providing a great chance to learn about how plants develop and change in the forest as light fluctuates.

April 5–April 19
Macy’s Flower Shows
Various locations
Macy's annual Flower Shows will be on display this year at Macy's Herald Square in New York City, Macy's on State Street in Chicago, Macy's on the Nicollette Mall in Downtown Minneapolis, Macy's Union Square in San Francisco and at Macy's Center City Philadelphia. Macy's Flower Shows feature vast flowering landscapes, fantasy bouquets and seminars and events that usher in spring. Free to the public.

April 11
Free Guided Tour
Scott Arboretum of Swarthmore College
Swarthmore, Pa.
The Crum Woods of Swarthmore College encompasses 220 acres of mostly forested land straddling the Crum Creek in Swarthmore. Join members of the Crum Woods Stewardship Committee to learn about the plants, wildlife, and geologic history of the woods.

April 17–30
Jurassic Gardens
Denver Botanic Gardens
Denver, Colo.
Jurassic Gardens depicts prehistoric plant/animal relationships with life-sized, realistic dinosaur figures plus prehistoric plants and their modern relatives. Plant fossils and a dinosaur dig site for kids round out the installation. This exhibit is the work of highly accomplished artist, fossil collector/preparation expert Guy Darrough from Lost World Studios.

April 17–19
Savannah Garden Exposition
Savannah, Ga.
This year’s theme is “Our Square Roots,” in honor of Savannah’s distinctive city planning and garden designs. Full-size exhibition gardens, informative demonstrations, children’s activities and an open-air market are just a few of the events, along with walking tours and a Southern-style tea.

April 19
Bonsai Exhibit
Brookside Gardens
Wheaton, Md.
The Brookside Gardens Bonsai Society will exhibit specimens in the Rose Garden (or indoors, if inclement weather).

April 24–25
Arbor Day Celebration
Lauritzen Gardens
Omaha, Neb.
On April 24 there’s a tree-planting ceremony in honor of individuals who have contributed to the garden’s development. April 25 brings special family activities, including tree walks and children’s art projects related to trees.

April 24–26
Garden Fair and Plant Sale
U.S. National Arboretum
Washington, D.C.
The Friends of the National Arboretum's annual Garden Fair and Sale presents new, rare and hard-to-find plants as well as plants from the finest specialty nurseries in the Mid-Atlantic. Proceeds benefit the U.S. National Arboretum's internship program, which invites horticulture students to work side-by-side with curators.

April 25
Wildflower & Native Plant Sale
Native Plant Center
Valhalla,  N.Y.
More than 50 kinds of native plants will be available for purchase.

April 25–26
American Daffodil Society Show and Conference
Chicago Botanic Garden
Glencoe, Ill.
More than 1,000 daffodils will be on display for judging at this national conference. Lectures and exhibits are open to the public.

April 25–26
Secret Gardens of the East Bay
Oakland area, Calif.
The annual Secret Gardens of the East Bay tour opens 10 select private gardens of California’s Bay Area to horticulture enthusiasts seeking inspiration or simply curious about intriguing garden spaces in their community. Proceeds benefit Park Day School, an independent K-8 school located in Oakland.

April 30–May 2
63rd Annual Garden Symposium
Colonial Williamsburg
Williamsburg, Va.
A natural rhythm is always present in our gardens. The theme of Colonial Williamsburg’s 63rd Garden Symposium is “The Natural Rhythm of Gardening,” which focuses on creating gardens that are both aesthetically rich and ecologically sound. Speakers will share tips that promote healthy plants, beautiful landscapes and responsible gardening. Speakers include author Felder Rushing, Renee Shepherd of Renee’s Seeds, and landscape architect James van Sweden. The symposium takes place May 1, with optional tours April 30 and May 2.

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