GOFFSTOWN – Evergreen, the one-acre woodland garden with more than 400 mature rhododendrons, opens to the public without charge May 31 through June 2.

Evergreen is always open on the first weekend of June because that’s when its 220 Catawba rhododendrons are at peak bloom, according to Claire Baker of the non-profit Evergreen Foundation, which owns and maintains the garden.

Evergreen also includes sweeps of 175 rosebay rhododendrons (Rhododendron maximum), which bloom in July.

“Many of the rhodies are over 25 years old,” Baker says, “so they’re enormous – some are ten feet high – and they’ve grown into huge masses. When they’re in bloom, they’re spectacular.”

Photos and descriptions of Evergreen are on the Evergreen Foundation’s extensive website, evergreenfoundation.org.

Many of Evergreen’s rhododendrons are mass-planted on nearly 400 feet of berms, some of which are 10 feet high. Berms are artificial but natural-looking ridges that create privacy by screening the property from neighboring houses and other development.

“Evergreen shows how typical homeowners can create the extensive and secluded gardens normally found only on much bigger properties,” Baker says.

The garden is shaded by mature white pines – some are two to three feet thick at the base–and it’s planted with sweeps of low-maintenance, shade-tolerant, broad-leaf evergreen shrubs and ground covers.

Evergreen also has a seasonal cascading brook and several large outdoor “rooms” defined by large granite boulders and rhododendron-planted berms.

The White Room is named for the blossoms of its rosebay rhododendrons, its cast-iron bench and cherub sculpture – all are white – and for its variegated euonymus and hosta, both of which sport large white splotches in their foliage.

The Gold Room is named for its large sweeps of ‘Emerald ‘n Gold’ euonymus and Vinca minor ‘Illumination’; both produce leaves with heavy yellow variegation. The space is partly bounded by the two biggest granite boulders in the garden: the largest is 12 feet high and 20 feet wide.

Created by landscape designer Robert Gillmore, Evergreen has been open to the public without charge since 1994.

It has been featured in many newspapers and magazines, including Fine Gardening and New Hampshire Home, as well as in Gillmore’s two landscaping books: The Woodland Garden and Beauty All Around You: How to Create Large Private Low-Maintenance Gardens, Even on Small Lots and Small Budgets.

Evergreen will be open from 10 a.m. to 5 p.m.

It will be described in a free brochure keyed to numbered posts along its quarter-mile of paths.

Because plants along the paths can be easily damaged, pets and children younger than 12 years old cannot be admitted.

Evergreen is not wheelchair accessible but its paths are “gently graded,” Baker says.

To reach the garden, take Route 114 to Goffstown village and turn onto Summer Street (next to Sully’s Superette). Evergreen’s Garden Cottage is at 42 Summer Street, the eighth house on the right. Visitors are asked to park on the garden side of the street.

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