Because they are so much larger than most perennials, flowering shrubs are great choices for maximizing fragrance. They are generally low maintenance and provide winter structure, plus early spring greenery.
Azaleas: Many native deciduous azaleas have highly fragrant flowers in pastel pinks, yellows, and whites; including the coast azalea (rhododendron atlanticum), zones 5–9; the sweet azalea (r. arborescens), zones 5–9; the pinxterbloom azalea (r. periclymenoides), zones 4–9; the roseshell azalea (r. prinophyllum), zones 4–9; and the swamp azalea (r. viscous), zones 4–9.
Banana shrub (Michelia figo): Powerful fruity fragrance and lustrous evergreen foliage; blooms spring through summer; 10 by 10 feet; zones 7–10.
Box-leaf azara (Azara microphylla): Small but richly fragrant flowers smell of white chocolate in late winter and spring; sun to part shade; 30 by 12 feet; zones 6–9.
Buffalo currant (Ribes odoratum): Powerful clove-scented yellow flowers in spring; 6 by 6 feet; zones 5–8.
Carolina allspice or sweetshrub (Calycanthus florid us): Dark red 2-inch flowers in summer; sun or part shade; 8 by 10 feet; zones 5–9.
Daphnes (Daphne x burkwoodii): Carol Mackie and Somerset produce powerful fragrance from small white or purplish flowers in late spring; 3 by 3–5 feet; zones 4–7. Many other daphne species are also highly fragrant, including garland flower (d. cneorum), alpine daphne (d. alpina), Caucasian daphne. (d. caucasica), winter daphne (d. odora), February daphne (d. mezereum).
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Fragrant tea olive (Osmanthus fragrant): Strongly fragrant, very long-blooming (from autumn to spring) evergreen shrub; excellent container plant; sun to part shade; 20 by 20 feet; zones 7–10.
Gardenia (Gardenia jasminoides): Long-blooming evergreen shrub producing white flowers in summer with extraordinary creamy fragrance; light shade; 4 by 4 feet; zones 7b–10.
Japanese pittosporum (Pittosporum tobira): Wonderfully fragrant flowers in early summer with evergreen foliage; 2 to 8 feet high; zones 7–9.
Lilacs (Syringa): Of the hundreds of varieties of this popular 8- to 10-foot high shrub, the most highly fragrant and disease-resistant choices for zones 3–7 are: Henri Robert, Excel, Vauban, Rhum von Horstenstein and Miss Kim. Gardeners in zones 8 and 9 need to choose heat-tolerant lilac varieties such as Angel White, Big Blue, Blue Skies and Lavender Lady.
Mexican orange blossom (Choisya ternata): Superb rounded evergreen shrub with 1-inch white star-shaped flowers in late spring, again in fall; shade or part shade; 6 by 6 feet; zones 7–10.
Mock orange (Philadelphus coronaries): Most species and varieties of this old-fashioned favorite have strongly-scented showy white flowers in early summer; 10 by 8 feet; some hardy to zone 3. Paper bush (Edgeworthia gardenii) yellow flowers in late winter; 5 by 5 feet; zones 7–10.
Sweet box (Sarcoccoca hookeriana and S. confuse): Small white flowers with heady fragrance in late winter; evergreen; part shade to shade; 3 by 3 feet and 6 by 6 feet, respectively; zones 7–9.
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Sweet pepperbush or summersweet (Clethra alnifolia): Showy 6-inch clusters of white flowers in late summer; shade to partial shade; 6 by 8 feet; zones 3–9.
Viburnums (V. carlesii): Powerfully fragrant small white flower clusters in spring; sun to partial shade; 6 by 6 feet; zones 5–8. Many other viburnums are also highly fragrant.
White forsythia (Abeliophyllum distichum): Showy 1/2-inch flowers in late winter; 5 by 5 feet; zones 4–9.
Winter hazel (Corylopsis glabrescens): 1-inch yellow flowers in early spring; partial to full shade; 15 by 15 feet; zones 6–9.
Wintersweet (Chimonanthus praecox): 1-inch yellow flowers in late winter; 12 by 12 feet; zones 6–9.
Witch hazels (Hamamelis mollis, H. vernalis, and hybrids): Long-lasting spidery yellow, orange, or red flowers open in winter; part shade or sun; 15 by 15 feet; zones 4–8.
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