Syringa × prestoniae
Common name: 
Preston Lilac
Canadian Lilac
si-RING-ga pres-TON-ee-ie
Native to (or naturalized in) Oregon: 
  • Deciduous shrub or small tree, vigorous, to 8-12 ft (2.5-3.5 m) tall, upright, rounded, very hardy.  Leaves simple, opposite, oval to elliptical, 15 cm long, dark green.  Flowers generally single, often lavender to red-purple, but also pink and white, small tubular, in upright, large pyramidal clusters (panicles), some have mild fragrance; bloom in late spring or early summer.
  • Sun.  Prune occasionally to maintain a fuller base
  • Hardy to USDA Zone 2 or 3
  • Syringa × prestoniae was the result of a cross between S. reflexa × S. villosa and first raised by Miss Isabella Preston at the Central Experimental Farm, Ottawa, Canada in 1920.  They often visibly resemble their S. villosa (Late Lilac) parent.  Most are late blooming, some 2 weeks or more after the Common Lilacs.  Miss Preston was responsible for naming at least 71 selections from her initial crosses (most of her selections were named in honor of Shakespearian women).  The resulting progeny of her crosses came to be known as the "Preston Lilacs", sometimes referred to as the "Canadian Lilacs".  Additional crosses, utilizing the same parentage, have been made by a variety of other horticulturists as well.   Not all of the plants within the "Preston Group", however, are of the same parentage.  Some of the other species of lilacs involved in the "Preston" lineage include Syringa josikaea and Syringa oblata.  The progeny of those plants, developed through the hybridization of Syringa josikaea and Syringa reflexa, is referred to, taxonomically, as Syringa × josiflexa.  The progeny of this hybrid is also sometimes referred to as "Preston Lilacs".  Over 35 selections have been named by a variety of other hybridizers.  However, there are relatively few selections which are actually available to the trade. (Reference: Ohio Nursery and Landscape Association, Plant Selection Committee, 1998).  Some of the superior and available selections include:
    • 'Agnes Smith'  -  flowers white, single, fragrant, late blooming, hardy, USDA Zone 2 (Snyder, 2000), an introduction of Owen Rogers of the University of New Hampshire; ‘James Macfarland’ × unknown, therefore a S. × josiflexa.  Apparently marketed in Germany as Miss USA™ and Miss America™ (Inter. Reg. and Checklist of Cultivar Names in the Genus, Syringa L., 2005).
    • 'Alexander's Pink'  -  flowers pink, in large clusters, fragrant, to 6-9 ft (1.8-2.7 m) tall, reportedly hardy to USDA Zone 2.  A hybrid of (S. × josiflexa 'James Macfarlane') × (S. × prestoniae 'Ethel M. Webster').
    • 'Donald Wyman'  -  flowers purple in the bud, opening to red-purple, single.
    • 'Isabella'  -  single mallow-purple flowers in erect clusters, resistant to mildew, hardy to USDA Zone 2 (Snyder, 2000).
    • 'James Macfarlane'  -  flowers are true pink and freely produced, an introduction of the University of New Hampshire (S. × josiflexa).
    • 'Minuet'  -  light purple in the bud opening to soft, pinkish white, soft, whitish pink flowers (S. × josiflexa 'Red Wine') × (S. × prestoniae 'Donald Wyman').
    • 'Miss Canada'  -  pink flowers, grows upright to 10-12 ft (3-3.5 m) tall and wide, can form a large rounded shrub or can be grown as a small tree, hardy to USDA Zone 2, blooms about a week later than most Common Lilacs.
    • 'Red Wine'  -  flowers single, magenta (S. × josiflexa).
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