Tour the Duke Herbarium

Passiflora specimen, courtesy of Duke Herbarium

By Kathleen M. Pryer

Just what makes an oak an oak or a pine a pine? Until recently, it was based upon what we could see about a plant. For centuries, botanists and plant collectors have searched for plants in remote and isolated jungles, in urban waste lots and along railroad tracks, in order to document the diversity and distribution of the earth's flora.

The dried plant specimens are stored and studied in herbaria, which can be thought of as a library of plant life. As we lose natural habitats across the world, herbaria provide a record of plant life, and they serve as a repository of precious genetic information. Herbaria hold the tools for our understanding of the plant world.

Each herbarium specimen is key to understanding plant relationships, geographic distributions and economic usefulness. More recently, genetic and molecular studies using herbarium specimens have allowed us to see plants at an entirely different level. This refinement in our understanding of how plants may be related is a dramatic story in the botanical world.

Some early herbaria were established in Europe in the early 1600s, a time of great exploration. New plants were being found at such a rate that botanical gardens could not keep pace by growing living examples of every new species found. Representatives of many known (and even undescribed) species of plants can be found in herbaria today, carefully mounted on sheets of archival quality paper, labeled with important collection information about them, and stored on shelves in cabinets in climate-controlled rooms.

All in all, the quiet herbarium holds a fascinating story. At the Duke University Herbarium you can see 800,000 diverse specimens of algae, fungi, lichens, mosses and vascular plants. These include samples of rare passionflowers discovered in the 1970s by Duke scientists working in Costa Rica, grasses from the 1890s Biltmore Estate, and Amborella, a small shrub found only on the island of New Caledonia in the South Pacific.

Duke Gardens is offering a tour of the Duke Herbarium on March 4 from 3 to 4:30 p.m. You will have the opportunity to see the collection, hear from a botanist who studies and manages it and learn about the amazing work being done across the globe. For information or to register, please call 668-1707 or e-mail slsmith@duke.edu.

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.

Kathleen M. Pryer is director of the Duke Herbarium and an associate professor of biology at Duke. This column first ran in the Durham Herald-Sun on Feb. 19.

For more Duke Gardens classes and special events, please see this previous post.

Adiantum specimen, courtesy of Duke Herbarium

Garden design: where to start?

By Lauren Sims
Photo by William Cullina

This spring, many of us will head to a local nursery or garden center and select a few new plants for our yards. Perhaps you are looking for a couple of containers to sit on the front porch, or maybe some brightly colored annuals to line the path to the door. This seems simple enough, right? But for a lot of people, “designing” a garden space is a completely different and more daunting endeavor.

“I think design is intimidating for most people,” says William Cullina, a gardening author and director of horticulture at the Coastal Maine Botanical Gardens. “There’s a sense that there’s a right way and there’s a wrong way to do it, and if you do it wrong it’s out there in your front yard and everybody is going to see it and you’ll be embarrassed.”

But Cullina is quick to point out that garden design does not have to be intimidating, and there is no such thing as right and wrong.

“In a sense, design is all about perception, right? It’s our perception of beauty.”

Some homeowners like the idea of a garden space that blends in with the natural landscape surrounding it, or one that suggests a landscape that they wish surrounded them, says Cullina, who counseled many Triangle gardeners back when he was nursery manager at Chapel Hill’s Niche Gardens. Others prefer a more abrupt design that sets the garden apart from its surroundings. Choose what you like, he says; no one aesthetic is better or worse than another.

One key to designing a garden space is to take the time to think abstractly, Cullina says. Right now, before that spring trip to the garden center, is the perfect time to play around with new ideas. Daydream about what you would like for and from your garden. Sketch out some ideas. Take digital photos of plants, or cut them out of a seed catalog, then lay them out and shuffle them around to see if and where you like them. And if you don’t like what you see, just grab a new piece of paper or snap a few more photos and experiment some more. No harm done.

The most important part of garden design is to enjoy yourself, says Cullina.

“Everybody has an opinion about what’s beautiful and everybody thinks that their opinion is the best one,” he says. “So I think you have to take it all with a grain of salt and have fun with it.”

You can learn more from Cullina when he visits Duke Gardens for two special events this month. On Feb. 12, from 9 a.m. to noon, he’ll lead a workshop called “Beyond the Surface: Soil Demystified.” Then from 3 to 5 p.m., he’ll present a talk titled “The Botany of Design.” For more information, please call 668-1707 or e-mail slsmith@duke.edu. To see Duke Gardens’ full roster of discovery programs, please go to gardens.duke.edu.

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.

Lauren Sims is a graduate student at Duke Divinity School and a work-study assistant at Duke Gardens. This column first appeared in the Durham Herald-Sun on Feb. 5, 2011.

Training new docents. Join us!

Duke Gardens is pleased to announce the dates for this year's docent training. We are expanding programming in children’s education and hope to train 7 or 8 new children's docents. We would also like to offer more trolley and walking tours in our adult tour program.

Docent trainees must attend each of the three trainings listed below. The deadline to sign up is Feb. 16.

Dates: February 21, 23 and 25

Time: 9 a.m. to noon

Please contact Chuck Hemric if you would like to sign up or are seeking more information. You can also read more on our website about our volunteer opportunities in education, as well as other volunteer opportunities.

Thanks for your interest!

Soil Demystified

By Lauren Sims
Photo by William Cullina.

Red clay soil, like sweet iced tea, is an ever-present and oft-romanticized symbol of Southern living. However, not everyone waxes poetic about it. For many Triangle gardeners, the clay can be more of a bother than a blessing.

William Cullina commiserates.

Going through a gardening magazine and selecting plants you like may be a challenge for clay soil – some plants just don’t like to grow in clay, says Cullina, former nursery manager for Chapel Hill’s Niche Gardens and now director of horticulture at the Coastal Maine Botanical Gardens.

But don’t give up on your garden just yet. That same troublesome soil also has some great advantages. Cullina likens it to a sponge, absorbing and retaining both water and vital nutrients.

“Clay soils can be very fertile soils and rich soils,” he says, “if they are managed the right way.”

Those management techniques will be the subject of Cullina’s Feb. 12 workshop at Duke Gardens, “Beyond the Surface: Soil Demystified.”

The growth and activity that is ongoing below the ground in a garden is really more important that what you see above the ground, says Cullina. “But it’s hard for us to get a handle on it, since we don’t live underground and we’re not microscopic.”

Cullina aims to make the science of soil intriguing and accessible to home gardeners, so that they can tie it in with their everyday horticultural practices. He has helped many a home gardener with his books on plants, including “Understanding Perennials: A New Look at an Old Favorite” and “Native Trees, Shrubs and Vines: A Guide to Using, Growing, and Propagating North American Woody Plants.”

Healthy soil contributes to healthier plants and greater ecological function, and Cullina encourages natural methods to maintain it. There are organic solutions to every situation that are more effective than synthetic solutions for a lot of different reasons, he explains. And the more living material those organic solutions involve, the better.

One common practice is to add compost, or organic soil amendments, to your garden. Effective organic amendments have two components: the living and the dead. If you purchase compost directly from the supplier who produces it, you’ll receive not only the dead material but also a wide array of living micro- and macro-organisms that can feed and enrich your home garden.

It is, at its core, a simple idea. “This is just nature,” he says. “This is the way that life on earth has functioned for millions of years.”

Cullina’s soil workshop will be from 9 a.m. to noon in the Doris Duke Center. He will also make a presentation titled “The Botany of Design” from 3 to 5 p.m. For information or to register for either event, please call 668-1707 or email our registrar. You may also read more about these events and others in our full program guide (PDF), or glance at a full list of Jan.-June 2011 classes.

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.

Lauren Sims is a graduate student at Duke Divinity School and a work-study assistant at Duke Gardens. This column first appeared in the Durham Herald-Sun on Jan. 29.

Annuals or Perennials?

The echinacea coneflower is among perennials
that live for a long time.

By Lauren Sims
Photo by Alice Le Duc

As we prepare to flip to the next page on the calendar, we are reminded that spring is inching ever closer. That means it’s time to start thinking about our spring gardens, and one of our initial planting questions may be, “Annuals or perennials?”

Bill Cullina, author of Understanding Perennials: A New Look at an Old Favorite and other plant books, and director of horticulture at the Coastal Maine Botanical Gardens, would have us ask an even more fundamental question first: "What does it mean for a plant to be perennial, anyway?"

Often, says Cullina, people operate under the assumption that “perennial” indicates a plant that continues to grow and bloom for many years. While some perennials do last for generations, many of them only live for a few years. Perennial plants must store away enough energy to survive months of dormancy every year and regenerate the following season. This is a costly process, and many of the plant’s resources are invested in preparing for and living through this dormant period.

Annuals, on the other hand, have no need to store energy or conserve resources. They give everything they have for a short period of time, burning brightly but extinguishing quickly. The biological strategy for annuals is to produce the most seed possible.

“So it’s hard to find perennials that bloom the way an annual plant does or a tropical plant does, that doesn’t have to worry about stocking things away for the dormant season,” says Cullina, whom local gardeners may recall from his days as nursery manager at Chapel Hill's Niche Gardens.

“The idea of the non-stop blooming perennial, while there are a few things that might fall under that category, is sort of a pipe dream because when it’s blooming it’s using up its resources.”

To learn more about perennial plants and the design opportunities they offer, join Bill Cullina on Feb. 12 from 3-5 p.m. for “The Botany of Design” presentation at Duke Gardens. Cullina will also do a 9 a.m.-noon workshop for a small group titled “Beyond the Surface: Soil Demystified.”

The fee for “The Botany of Design” is $35; $30 for Gardens members. The soils workshop is $70; $55 for members. For more information or to register, please call 668-1707 or e-mail registrar Sara Smith. Please also see our online education booklet (PDF) for other discovery programs for adults and children.

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.

Lauren Sims is a graduate student at Duke Divinity School and a work-study assistant at Duke Gardens.

Duke Gardens: Exploring Winter Botany

Article by Lauren Sims
Photos by Rick Fisher

For many, a walk through the woods to identify plants is an activity restricted to the spring and summer seasons. Plants, after all, are identified by their leaves—nature must be in bloom in order to learn about them. Right? Not so fast, says Ken Moore.

“Take a walk in the woods in the wintertime, and try and contrast it with a similar walk that you would make in the middle of the summer,” says Moore, the former assistant director of the N.C. Botanical Garden. “In the wintertime, you don’t have all those leaves on the trees. So you can really see the whole nature of the landscape. You can see the ups and downs, you see the beautiful architecture of the whole forest.”
A forest is lovely in the summer, Moore says. But despite the cool shade and the vibrant greens, “you can’t really see the forest because of the leaves. You’re so busy looking at the color of trees and flowers and the texture of ferns, you’re sort of unaware of the characteristics of individual plants.”

“With all the leaves gone, you’re forced to concentrate on other aspects of the plants,” he says. And, surprisingly, bare branches can actually be more clearly identifiable than foliage. According to Moore, leaves on the same plant may vary widely in their color, their size and even in their shape. In many cases, using them for identification purposes can be more confusing than helpful. More stable identifiers like bark and the configuration of buds at the ends of branches are often a surer bet, and they are showcased during the winter months.
Winter may appear to be a barren or uninteresting season for nature lovers, but do not be fooled. There is much to learn about your favorite plants this time of year. In fact, you may come to prize those winter nature walks even more than their summer counterparts.

“Most of us walk around in the winter saying, ‘I don’t know what any of these things are, I’ll have to wait until the leaves come out so I can tell you.’ My feeling is, ‘I can’t wait until the leaves all fall off, and then I can have the forest back!’ ”
To learn more about nature in winter, consider taking Moore’s “Winter Botany” 2-day class at Duke Gardens on Jan. 23 and 30 from 1 to 4 p.m. For information or to register, call 668-1707, e-mail the registrar or see page 12 of our full education brochure (PDF).
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.

Lauren Sims is a graduate student at Duke Divinity School and a work-study assistant at Duke Gardens. This article first appeared in The Herald-Sun on Jan. 15.

Duke Gardens greeting cards are here!

Duke Gardens' 2010 greeting cards are in, and they're available for sale at the Terrace Shop -- a fantastic gift for your nature-loving friends and family.

The first four images below come in a 12-pack of 4x6 cards for $10. The final image is our winter scene, which you can buy as individual 5x7 cards for $2.

If you're a Duke student or employee, you can get 20 percent off those prices during the holiday sale through Dec. 23. (That applies to our 2011 wall calendar, too. See a PDF preview.) Be sure to bring your i.d.

Ayamebashi (Iris Bridge) in the W.L. Culberson Asiatic Arboretum. Photo by Lee Capps.

Wisteria-covered Pergola in the Terrace Gardens.
Photo by Alice Le Duc.

Great blue heron in the Virtue Peace Pond in the Doris Duke Center Gardens.
Photo by Tamara Kilbane.

Bird-Watching Shelter in the H.L. Blomquist Garden of Native Plants.
Photo by Ed Albrecht.

Blomquist Gate House. Photo by Rick Fisher.