Fall Plant Sale Preview: Native Grasses

Native grasses in the Piedmont Prairie. Photo by Sue Lannon.

 By Annabel Renwick
Horticulturist
Blomquist Garden of Native Plants at Duke Gardens

Autumn brings cooler, shorter days and helps the garden transition from summer into winter. By September many of our garden plants have finished blooming and frequently gone to seed, but not so in the Blomquist Garden’s Piedmont Prairie. Many of the late flowering, native grassland species are just coming into flower, such as the asters and goldenrods, so it’s not surprising that so many of these late flowering U.S. natives have been cultivated as garden plants worldwide, extending the enjoyment of gardens until the arrival of frost.

Eragrostis spectabilis.
Photo: USDA-NRCS Plants Database. 

September is also the time when many Southeastern native grasses are in flower along North Carolina roadsides. It may come as a surprise to many, but grasses do have flowers. The tiny flowers or spikelets are formed on a flowering stem, known as an inflorescence, with the more “ornate” grasses having highly branched inflorescences or panicles. Some of these panicles can be so intricately branched that they appear as airy mounds of transparent fine lace. Purple love grass (Eragrostis spectabilis) is one such species that has to be my favourite native grass planted in an ornamental setting. The gray goldenrod (Solidago nemoralis), Black-eyed Susan (Rudbeckia hirta) and smooth blue aster (Symphyotrichum laeve) make super planting companions with purple love grass.

Particularly striking are the taller grasses such as Indian grass (Sorghastrum nutans) with its masses of golden, oat-like  panicles, and sugarcane plume grass (Erianthus giganteus), with its clusters of silvery plumes shooting skyward. Stipa gigantea (giant feather grass), a stunning grass with arching flowering stems reaching 6 feet, is a stalwart of English Gardens but as a Mediterranean native doesn’t adapt well to North Carolina’s  hot and humid climate or heavy clay soil. Indian grass would easily make a marvelous replacement for S. gigantea in a North Carolina Garden.

Sorghastrum nutans in the Piedmont Prairie. Photo by Cathi Bodine.

The striking Erianthus giganteus works well at the back of a border and could replace the commonly grown (and sometimes invasive) Miscanthus sinensis (Chinese silver grass) in local gardens. Generally grasses prefer growing in sun or may tolerate partial sun, but they will not thrive in shade.  Many local grasses are drought tolerant and prefer nutrient poor soil; they will grow in our local heavy clay soil, and as with most grasses they are deer tolerant.

Grasses have been used in ornamental plantings in the U.S. for more than 100 years. One of the earliest proponents of incorporating native grasses into U.S. landscapes was the Danish-born Jens Jensen who, at the turn of the 20th century, belonged to the Prairie School style of design based on the Arts and Crafts movement established in Great Britain during the latter part of the 19th century. In more recent decades, Dutchman Piet Oudolf has echoed Jensen’s philosophy, designing and installing grass dominated landscapes including the Highline in New York City.

Oudolf has written many design books using grasses, but one of my favorites is “Gardening with Grasses,” by Michael King and Piet Oudolf (1998). A second recommendation is “The Encyclopedia of Grasses for Livable Landscapes,” by Rick Darke (2007).

Come to Saturday’s Fall Plant Sale and you’ll find these beautiful native grasses and many more.

FALL PLANT SALE DETAILS:
Date: Saturday, Sept. 29, 2018
Time: 9 a.m.-noon
Member benefits: Duke Gardens members get 10% off all purchases, plus access to the members-only previews sale from 8-9 a.m., and a full list of plants in advance! Join online or on site beginning at 7:30 a.m.
Parking: Free.
Pets not permitted. Please see Duke Gardens' pets policy here.
Wagons + boxes: Our supply is limited; please bring your own if possible, and you'll have more time to spend gathering beautiful plants.
Your support helps Duke Gardens to provide summer internships to aspiring horticulturists from across the nation.
Please see our event page for more information, and we'd love for you to spread the word by sharing the event on Facebook and inviting your friends.
Thank you!

Plant Sale Preview: See Fall Beauties in Person

Hedychium coronarium, or white ginger lily.
Photo by Jason Holmes.

By Rose James
Duke T'20

Shopping at Duke Gardens' Fall Plant Sale can require a bit of imagination sometimes: you plant these bulbs near this tree and that shrub, anticipating what they will all look and smell like many months from now.

But for fall beauties, you don't have to wait. Simply take a stroll through Duke Gardens right now, and you can get a preview of some of the delights we'll have waiting for you at our Sept. 30 sale.

Start by following your nose to Osmanthus fragrans, also known as the fragrant tea olive. Visitors can never get enough of this vibrant plant's intoxicating scent, and they always want to know more about it. Native to the Himalayas, China and Japan, this is a hardy plant with an exceptionally long bloom period, up to two months during the fall. It can grow up to 30 feet tall, although the typical height ranges from 10 to 12 feet. You can find fragrant tea olives blooming in various areas of Duke Gardens. If you are near it, you will not be able to miss its amazing smell. You can read more about it in this fall 2016 blog post.

The Osmanthus fortunei will also be featured at the plant sale. It is commonly known as fortune's tea olive, and it produces small, white flowers during the fall. It is a fragrant evergreen that is particularly resistant to deer. Bigger than the typical Osmanthus fragrans, fortune's osmanthus can grow to be 15 to 20 feet tall and equally wide. It does well in sun and shade gardens, and it is drought resistant. If you are looking for a hardy yet sweet-smelling plant to enhance your garden, look no further than the Osmanthus fortunei.

Muhlenbergia capillaris.
Photo by Jason Holmes.

The Hedychium coronarium, called the white ginger lily, is an herbacious perennial native to the Himalayas that flowers from August to October. It is a fan-favorite for showy, fragrant flowers. With blooms said to resemble white butterflies, the white ginger lily is an excellent addition to any garden that gets full sun or partial shade. The lily will grow to be 3 to 6 feet tall with a spread of 2 to 3 feet. It can be found along the banks of North Pond (just south of Yearby Avenue) in the Asiatic Arboretum. Follow your nose, and you are sure to find it.

Another plant currently in its dazzling season is Muhlenbergia capillaris, commonly called pink muhly grass. This is a perennial Asian grass that grows to be 2 to 3 feet tall and equally wide. This is a low maintenance plant that has a gorgeous spread of pink flowers in the fall months. It is a wonderful addition to any garden that gets full sun or partial shade, and when it is not in bloom, it features glossy green leaves and stems, making it beautiful year-round. You can see this grass in the Doris Duke Center Gardens, including on the hillside adjoining the lower parking lot.

Callicarpa cathayana. Photo by Rose James.

If you are looking for color for your garden, you need to check out Callicarpa cathayana -- also called beautyberry, and for good reason. This is a deciduous shrub that grows to be 4 to 8 feet tall and 3 to 6 feet wide. Like the pink muhly grass, the beautyberry is best suited to full sun or partial shade gardens, and it is low maintenance. The real treasure of this plant is its plentiful purple berries, preceded by pink and purple flowers. This plant will attract birds in the fall, when the berries emerge. It is a must-see in Duke Gardens.

We hope your Duke Gardens visit whets your appetite for the vast array of plants we'll have at the Fall Plant Sale. Our expert horticulturists will be happy to talk to you about ideal plants for your garden conditions and gardening style. Duke Gardens members will get 10 percent off all purchases -- you may join in advance or on site. We look forward to seeing you here!


Fall Plant Sale details:

Date: Saturday, Sept. 30, 2017
Time: 8 a.m.-noon
Membership benefit: Duke Gardens members get 10% off! Join now or on site.
Parking: Free.
Pets not permitted
Wagons & boxes: Our supply is limited; please bring your own if possible, and you'll have more time to spend gathering beautiful plants.
Please see our event page for more information, and we'd love for you to spread the word on Facebook. Thank you!

Give the Gift of Duke Gardens!

By Sarah Leach Smith

 

There’s no denying the cooler temperatures and the falling leaves – the winter holidays are approaching. For many people, it’s a stressful time of year. What will I bring to the meal/give as a gift/wear to the party? Here at Duke Gardens, we may not be able to answer ALL of your questions, but we can certainly help with a few of these things.

Have you ever considered the gift of a Friends of Duke Gardens membership? It’s a wonderful idea for people who live in Durham or the surrounding areas. Because Duke Gardens is free for all visitors, more than half of our yearly operating budget comes from our members, who value all that this botanic garden has to offer.

 

Membership not only supports the future of Duke Gardens, but it also comes with great benefits for members. All membership levels include discounts for education programs and gift shop purchases, invitations to specials Friends of Duke Gardens events, reciprocal admission to nearly 300 gardens in North America and a copy of our annual Friends publication Flora.

To supplement the gift of membership, consider a special Duke Gardens souvenir item! In the Terrace Shop, we have a beautiful assortment of Duke Gardens books, mugs, T-shirts and 2016 calendars. We also have unique items handmade by the Garden Guild, a group of very crafty Gardens volunteers. Stay tuned for more information about these items.

If you’d like to give a gift of a Friends of Duke Gardens membership, please give us a call. Development Assistant Millicent Snow would love to hear from you and may be reached at 919-668-1711.

Happy Holidays!

Why is fall best for planting?

Jason Holmes, center, 

advises customers about plant selection

at last year's Fall Plant Sale

By Jason Holmes

Ahh, the season of fall is almost upon us, and we gardeners are coming out of summer semi-hibernation, during which we emerged only to water the plants we planted in early spring, hoping they made it through those hot, dry summer months.

Many of us know that fall is the best time to plant shrubs and trees. We hear it all the time. But let’s face it, we see plants we love, with those nice big flowers or that beautiful combination we just have to have, and that sage advice sometimes gets forgotten. For me, buying plants in spring is often an impulse, and I spend much of my time watering those plants on 90- to 100-degree afternoons.

People often ask, “Why is fall the best time to plant?” The answer is simple: As the plants go dormant above ground, roots will continue to grow underground until the ground temperatures fall below 40 degrees Fahrenheit.  So for most of the country, this statement is true from mid-September through mid-December.

Here is an example: if you plant a tree in the spring, it must acclimate to the new site, producing new growth like leaves, flowers and sometimes fruits. It must also produce roots as well! This means you will need to water more often while your tree acclimates to its new situation before the summer heat and often dry weather arrives. Now, plant the same tree during the fall, and soon after the plant will begin to go dormant above ground, but the roots will still have several months to continue growing underground. This is giving the plant a “head start” for the next spring as it produces strong new growth.

Annuals and perennials are great to plant during the spring and fall. As long as they are watered until they are established, they fare very well. I love to plant perennials in the spring, as they are waking up from winter dormancy, because they grow to fill in a space quickly. Perennials are often faster to grow into a space as opposed to trees and shrubs, and this gives us a chance to plant these in both seasons. So it is simple: anyone can plant anytime they want. I just hope I’ve explained well enough why fall is so ideal.

To help prepare you for your fall planting blitz, Sarah P. Duke Gardens will have its Fall Plant Sale on Saturday, Sept. 29, from 9 a.m. to noon. We will have a great variety of bulbs that bloom in late winter to early summer, fantastic perennials, useful herbs for cooking, and many unusual shrubs and trees, too. Many of these plants are propagated from Duke Gardens by dedicated staff and volunteers, who will be there to answer any questions you may have about gardening or plants in general.

If you want first dibs on all the plants, consider joining Friends of Duke Gardens, so you can attend the member pre-sale at 8 a.m. Non-members can join on site. Or call 919-668-1711 to join in advance. We hope to see you there.

Sarah P. Duke Gardens creates and nurtures an environment in the heart of Duke University for learning, inspiration and enjoyment through excellence in horticulture. The Gardens is at 420 Anderson St.

Columnist Jason Holmes is curator of the Doris Duke Center Gardens at Sarah P. Duke Gardens. This column first appeared in the Durham Herald-Sun.