Pine Mountain-Skeletal azalea branches are whispering with life at Callaway Gardens. Some bear modest bright green leaves and pink or white buds; others remain barren, in hibernation for a late summer bloom.

The exotics will come first, attracting people by the thousands in the next few weeks to Callaway, the garden attraction and resort about an hour's drive south of downtown Atlanta. And when admirers arrive to view more than 600 varieties of exotic and native deciduous azaleas, Hank Bruno, the garden's director of horticulture, will stand by, watching his perennial children dazzle visitors with varied shades of spring splendor.

Renee' Hannans Henry / AJC (ENLARGE)

Hank Bruno, director of horticulture for Callaway Gardens, predicts the resort's azaleas will bloom by late March.

(ENLARGE)

Azalea Trail, a popular springtime tourist attraction at Callaway Gardens, is showing hints of its expected late-March debut.

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He expects the exotic varieties to fully bloom by late March — roughly two weeks after white blossoms appear on a Shadblow, or serviceberry. Located by the Gardens Restaurant, the tree acts as a sort of spring sentinel for the azaleas, Bruno says. As the Shadblow bloomed last weekend, he knows his azaleas will soon explode with color.

"Most of the time, it's pretty accurate," says Bruno, garden curator here for 16 years.

He would know. Bruno learned from the late Fred Galle, Callaway's director of horticulture and later curator from 1953 to 1983. Galle authored "Azaleas," considered the definitive book on the gardens' signature attraction. He also saved varieties of azaleas from destruction when Atlanta's suburban boom in the 1960s threatened plants unique to the state.

"This is a legacy for me," says Bruno. "I take it somewhat personally, because he was a friend of mine."

The garden begins receiving calls in early March from people eager for azaleas. The plants are so popular, especially the bushy exotic Asian varieties, that the garden staff decided a few years back to post daily pictures of the perennials online, allowing viewers to see when the azaleas flower (go to www.callaway gardens.com, and then click Azalea Watch). The azalea exhibit is the underpinning of Callaway's Spring Celebration, which begins this weekend and runs through April 20. The event includes activities such as a plant fair and sale March 27-30, photography exhibits, fly-fishing classes, scavenger hunts and gardening courses.

The resort's azalea exhibit, which features upwards of 20,000 bushes, is in its 10th year. It is second only to Callaway's winter Fantasy in Lights show in popularity, says marketing director Rachel Crumbley.

Callaway focuses its azalea efforts in a few locations on its 13,000-acre grounds — along the scenic drive, the Overlook Garden (found within the azalea trail), and the Callaway Brothers Azalea Bowl, which opened in 1999. There, Bruno designed a collection of exotic and native azaleas, such as Kurume hybrids 'Yezo Nishiki', with pink and white buds; 'Fairy', which has a crisp salmon color; and a white 'Lemon Drop' swamp azalea. Bruno also incorporated pink and salmon-colored Chisolm-Merritts 'Eleanor' and 'Dorothy' in large sweeping color groupings.

Whites fade to blues to pinks, then reds to oranges and salmon shades.

Found at the feet of pines, dogwoods and crab apples, the exotics and natives have been pruned to blend effortlessly into each other. Exotics start resembling natives, and vice-versa, allowing a progression of shape and color.

Bruno begrudgingly names his favorites. Among exotics, he's drawn to the Chisolm-Merritt hybrid 'Begonia Rose' — a white bud sub-fused with lavender. Among natives, he favors flame azaleas in their varied fall hues, which grow rampant in colder Northern Appalachian states.

"It's a particularly under-appreciated plant," he says.

Though native varieties have been a mainstay at Callaway since its opening as a five-mile scenic drive in 1952, they are only now gaining a foothold in the Atlanta home landscape. For years, difficulty in propagation, as well as Georgia's long summer heat, made natives more of a novelty, he says. While exotic azaleas offer a bushy "meatball" appearance, natives grow taller and more tree-like, speaking more of a honeysuckle's airy limbs.

"We're growing these for their architectural form," he says. "Not just the flowers."

He understands the excitement people feel when viewing lush, sparkling new varieties: "When people get into collecting azaleas, it becomes an addiction."

However, his hope for this year's azalea exhibit is for viewers to set aside the stress of applying what they see in their own garden, and simply to enjoy the inherent message within the azalea itself.

"It's the harbinger of spring," he says. "I think there is a magic to that."

HANK BRUNO'S TIPS FOR SUCCESSFUL AZALEA GARDENING:

• Planting: Callaway's azaleas are planted in high shade roughly 5 to 6 feet apart. Soil should be amended with thick organic matter, and the pH is best at 5.5 or lower. Azaleas are light feeders; don't over fertilize. Once planted, try to avoid stressing the plant by moving it to a new location.

• Light: Azaleas need dappled sun, receiving some shade from structures like trees. However, they should be planted several feet away from the trunk of the tree to avoid root competition. Azaleas do not like afternoon sun and heat.

• Drought tolerance: For the first two years of life, azaleas require deep watering at 1 inch a week at the rootball unless there is rain. Once established, azaleas are very drought-hardy.

• Color: Consider how the color of the bark and flower will complement or clash with your home and other plants before putting the azalea into the ground. Bruno says while he prefers pastels, homeowners should consider large color groupings when planning their landscape.

CALLAWAY GARDENS SPRING CELEBRATION

This weekend through April 20 at Callaway Gardens, 17800 U.S. 27, Pine Mountain. Open 9 a.m.-5 p.m. daily. Adults, $13; ages 6-12, $6.50; ages 5 and younger, free. Admission for plant fair only (March 27-30), free. 1-800-225-5292, www.callawaygardens.com.