Plants of the Week – June 24

Are you a fan of unique and unusual plants like I am? If so, then you will love the eye-catching Eryngium ‘Big Blue.’ It features steel-blue flowers, stems, and leaves that will make a statement in any garden with its intense color and texture. Eryngium ‘Big Blue’ is salt-tolerant by the sea and its leaves, flower bracts and centers are all prickly like a holly, hence its common name: sea holly.

This plant starts out grayish-green then gradually transforms to electric blue from the top and spreads downward. Native to European mountains, it is related to thistle. Sea holly has a long bloom time and is excellent for both fresh and dried cut flower arrangements as it holds its famed blue hue. This plant has an intriguing form similar to that of a candelabra, having the biggest and tallest flower in the center surrounded by lower levels of smaller flowers. Eryngium ‘Big Blue’ is an easy-to-care-for perennial that is drought-tolerant once established. Deer will not even think about eating this prickly plant but bees love it. It prefers full sun and well-drained/sandy soil.

Photo Credit: Aaron D’Addio

Garden Location: Terry Shane Teaching Garden

What do you get when you cross Carolina allspice with Chinese allspice? If you are really lucky, you get Calycanthus x raulstonii ‘Hartlage Wine:’ a new interspecific hybrid that possesses the best features of both plants. Also known as Raulston allspice or sweetshrub, it is a fast-growing deciduous shrub that can reach up to 10 feet tall. This plant displays large and showy magnolia-like red wine-colored flowers over an extended bloom period with dark green, disease and deer-resistant foliage that turns yellow in autumn. Hartlage wine allspice was just released in 2000 by the J. C. Raulston Arboretum of North Carolina State University where it was developed by undergraduate student Richard Hartlage, thus explaining both the species and cultivar names. Calycanthus x raulstonii ‘Hartlage Wine’ can be cut back yearly to manipulate its size if desired. It prefers well-drained soil in full sun to part shade.

Photo Credit: Aaron D’Addio

Garden Location: Terry Shane Teaching Garden

Searching for a low-maintenance plant that looks its best all season long? Then look no further because Hakonechloa macra ‘Aureola’ is the perfect plant for you! Golden variegated Japanese forest grass is an ornamental grass unlike no other featuring narrow chartreuse leaf blades variegated with thin bright-green stripes running the length of each blade. It has an arching form that gracefully undulates with the slightest breeze, cascades over adjacent paths when used as an edging plant, or flows over containers or slopes. Golden variegated Hakone grass forms dense clumps that spread by stolons, but are slow-growers and not considered to be too aggressive, so they are often used in mass plantings.

Hakonechloa macra ‘Aureola’ is named after Mt. Hakone, a mountainous region of Japan where it is native; chloa, the Greek word for grass, and aureola, meaning golden. Placement of this plant in accordance to sun exposure is a tricky situation. The more sun exposure it receives the brighter golden color the leaves will turn; however, too much sun may bleach the leaves or transform them into mostly gold, thus losing the variegation.

On the opposite side, too much shade can result in the golden parts fading to lime green. So the best environment to grow this cultivar in is partial shade, thus creating a sharp contrast between the yellow and green leaf variegation. The Perennial Plant Association selected it as its 2009 Perennial Plant of the Year. Golden variegated Japanese forest grass pairs superbly with hostas that contrast it in both texture and color. This plant’s bright gold color will light up any partial shade garden. It grows best in moist, humus-rich, but well-drained soil and is resistant to deer, insects, and disease. Golden variegated Hakone grass should be watered regularly until established, cut down to the ground in late winter, and have its clumps divided every few years.

Photo Credit: Aaron D’Addio

Garden Location: Terry Shane Teaching Garden

Yucca filamentosa, also known as Adam’s Needle, is an evergreen shrub in the agave family native to the beaches of the southeast United States. It features flower stems that emerge from the center of the rigid, sword-shaped, spine-tipped, blue-green leaves and can reach up to 12 feet tall presenting showy, cream colored, bell-shaped, pendulous flowers.

Yucca filamentosa is readily distinguished from other yucca species by its white threads (filaments) on the leaf margins which are parallel veins that peel back as the leaf grows, eventually dropping off the older leaves. Adam’s Needle dies after flowering and fruiting, but produces offshoots at the base of the plant that develop into new plants. It attracts the yucca moth at night, its only pollinator. This plant prefers full sun, well-drained soil, and is tolerant of drought, rocky/sandy soil, and deer.

Photo Credit: Aaron D’Addio

Garden Location: John W. Nason Garden