Polly’s initial fascination with Stewartia—the handsome bark, the pristine flowers—led her to seek out and grow as many species as possible. She planted seeds and patiently waited decades to see the first breathtaking flower. Today the Polly Hill Arboretum’s Stewartia collection numbers over 70 trees with 9 distinctive trees named by Polly as cultivars.
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Plant Collections Network
Roses have been cultivated at the Montreal Botanical Garden since the 1930s. The Rose Garden was officially inaugurated in 1976. The collection has grown since then to become one of the most significant collections of its kind in North America, particularly in its species diversity. Of the 150-200 species taxonomists identify in the genus, 115 species are included in this collection. All but two of these species successfully overwinter at this USDA zone 4 site with no additional protection other than natural snow cover.
Since 2002, the Arnold Arboretum has been a member of the Plant Collections Network (formerly North American Plant Collections Consortium, NAPCC), a network of botanical gardens administered through the American Public Gardens Association in cooperation with the U.S. Department of Agriculture. The primary focus of the Plant Collections Network is the long-term preservation of germplasm for research. Participating institutions commit to holding and developing collections that are primarily organized at the genus level.
The Morton Arboretum was one of the first members of NAPCC and maintains six outstanding collections that have been recognized for their conservation value, high standard of curation, and institutional commitment to conservation. They are the linden (Tilia), oak (Quercus), elm (Ulmus), maple (Acer), magnolia (Magnolia), and crabapple (Malus) collections.
Longwood Gardens celebrates a long history of growing, hybridizing and displaying waterlilies going back to 1956. Its Nymphaea collection currently includes 97 taxa and became part of the Plant Collections Network (formerly North American Plant Collections Consortium) in October 2012. The majority of the collection consists of hybrids with a high number of tropical day and night-blooming varieties, in addition to hardy taxa and several species historically significant or frequently used by hybridizers.
The Agave collection focuses on Sonoran Desert taxa and was awarded accreditation in May 2010.
Cheekwood’s Dogwood (Cornus) collection, features 14 species and 23 cultivated varieties, We are honored to have the first dogwood collection included in the Plant Collections Network and to have the first recognized collection in the state of Tennessee.
The Morton Arboretum's Ulmus collection was accredited by Plant Collections Network, formerly NAPCC, in 2001.
Highstead’s Kalmia Collection is a one-acre concentrated display of more than 70 Kalmia forms and cultivars of 3 species set within a native stand of Kalmia latifolia that spreads across more than 55 acres of oak forest. This setting presents opportunities to view (1) how laurel species adjust and survive naturally within different habitats, (2) the immense range of cultivars that have been produced by horticulturists and can be cultivated in the home landscape, and (3) a restored woodland site with a naturalistic planting style.
The Morton Arboretum was one of the first members of Plant Collections Network (formerly NAPCC) and maintains six outstanding collections that have been recognized for their conservation value, high standard of curation, and institutional commitment to conservation. They are the oak (Quercus), elm (Ulmus), maple (Acer), magnolia (Magnolia), crabapple (Malus), and Tilia collections.