1. The Butchart Gardens, Victoria, British Columbia
You'd never believe this wonderland of floral displays on a Vancouver Island inlet started as an industrial wasteland. In 1904, Jennie Butchart began landscaping a played-out quarry left by her husband's cement business. Today, more than 1 million bedding plants keep the 55-acre gardens in glorious bloom from March into October. Illumination makes it even lovelier on summer evenings; 866/652-4422 or butchartgardens.com.
2. Mendocino Coast Botanical Gardens, Mendocino, California
Big waves provide the backdrop for this 47-acre property, which rambles along a rocky headland above the Pacific Ocean. Expect to enjoy blooming rhododendrons, camellias, daffodils, and Pacific Coast irises―plus the occasional migrating whale; 707/964-4352 or gardenbythesea.org.
3. Brookgreen Gardens, Pawleys Island, South Carolina
Archer and Anna Hyatt Huntington founded Brookgreen in 1931, stitching together 9,127 acres of former rice plantations stretching from the Waccamaw River to the Atlantic Ocean. Anna was a sculptor, and during the Depression the Huntingtons became patrons to many struggling artists. Today, the gardens harbor 2,000 species of plants, a wide variety of birds and animals, and an astonishing 550 outdoor sculptures; 800/849-1931 or brookgreen.org.
4. Marie Selby Botanical Gardens, Sarasota, Florida
The unusual core collection consists of epiphytes―certain orchids, bromeliads, and other "air plants" that grow attached to trees. You can see thousands of lovely, and sometimes weird, specimens. But alongside Sarasota Bay glittering in the sun, this 11-acre oasis also offers something that's even more rare: a profound sense of peacefulness; 941/366-5731 or selby.org.
5. Wave Hill, New York, New York
Soul-filling views across the Hudson River to the forested cliffs of the New Jersey Palisades make this a blissful haven amid New York City's bustle. The 28-acre property includes two former "country estate" mansions and an urban woodland. Washes of color from the many flower beds stand out dramatically against green lawns, trees, and shrubs. Everything builds to a peak in autumn, when the plantings are designed to take full advantage of the Palisades' fall foliage in the background; 718/549-3200 or wavehill.org.
6. The Bloedel Reserve, Bainbridge Island, Washington
Prentice Bloedel, a top executive for a timber company, loved nature. That's not the contradiction that it might seem; his company led the industry in recycling and reforestation. For their home, Prentice and wife, Virginia, shaped 150 acres on Bainbridge Island into an oasis of tranquillity. It's now an arboretum open to the public―by reservation only, to safeguard the serenity. Paths wander along meadows, marshes, forests, and ponds populated with waterfowl. The loudest sound you hear may be your own reverential breathing; 206/842-7631 or bloedelreserve.org.
7. National Tropical Botanical Garden, Kauai and Maui, Hawaii; and Coconut Grove, Florida
Chartered by Congress but privately funded, this organization administers gardens in Hawaii and Florida. It's scrambling to preserve tropical plants, many of which are rare or endangered. The Hawaiian gardens in particular are absolutely stunning. You can just show up at McBryde Garden, Limahuli Garden (both on Kauai), or Kahanu Garden (on Maui; it's the most coastal, with spectacular ocean views). You'll need reservations to tour Allerton Garden (next to McBryde) or The Kampong in Florida (call 305/442-7169). The admission charges, and any extra donations, help in the race against extinction; ntbg.org.
Note: Famed 20th-century plant explorer David Fairchild founded The Kampong and stocked it with plants from around the world. For more of his handiwork, visit Fairchild Tropical Botanic Garden in Coral Gables, Florida; 305/667-1651 or fairchildgarden.org.
8. Blithewold Mansion, Gardens & Arboretum, Bristol, Rhode Island
Sweeping views of Narragansett Bay and Bristol Harbor set off the 33 acres of lawn, garden, and mansion. The original owners loved the water (all the house's main rooms have bay views) and plants―such as an 85-foot giant sequoia known as the "Big Tree"; 401/253-2707 or blithewold.org.
9. Kingsbrae Garden, St. Andrews, New Brunswick
Kingsbrae―27 acres along Passamaquoddy Bay, compiled from the grounds of several grand old estates―will surprise you. The Scents & Sensitivity Garden, for example, is designed for the blind, with plants chosen for their scent or texture. The Gravel Garden displays plants that grow in gravel. More conventionally, it also features roses, perennials, and plants that attract birds and butterflies. Kingsbrae is open May 20 through October 8 this year; 866/566-8687 or kingsbraegarden.com.
10. Moody Gardens, Galveston, Texas
It began two decades ago as a barn and arena offering horseback-riding therapy for people with head injuries. The complex now includes outdoor and indoor gardens, an aquarium, a hotel, a spa, and a convention center. The best part: the Rainforest Pyramid, a 10-story wonderland of plants, animals, fish, and birds from rain forests around the world. Moody also still offers therapy programs and employment for people with disabilities; 800/582-4673 or moodygardens.com.
Honorable mention: McKee Botanical Garden, Vero Beach, Florida. Vero Beach, a charming, artsy town in the middle of Florida's Atlantic Coast, has resurrected a lost icon of the state's gloriously cheesy tourism history. McKee Jungle Gardens debuted in 1932, combining tropical landscaping, exotic animals, and swimsuit-clad ladies into a wildly successful package. Then came Walt Disney World and other new attractions. The gardens closed in 1976, and most of the 80 acres were developed. Local residents saw potential in the remaining 18 acres, raised money, cleared the riotous overgrowth, and reopened McKee Botanical Garden in 2001. The screeching monkeys and bathing beauties survive only in memory, but the restored McKee does reward visitors with lushly colored flowers and some delightful architectural oddities; 772/794-0601 or mckeegarden.org.
Links to hundreds of gardens worldwide: bgbm.org/idb/botgard.html