Seed Swaps: Fun Way to Get New Seeds!

It is that time of year again — seed swaps! National Seed Swap Day is Saturday, January 25, 2020, the last Saturday in January. Seed swaps are a great way to obtain new seeds, share your favorite seeds, and attend a fun event. A seed swap can be as simple as friends getting together to share seeds they saved from the previous gardening season to an all-day planned event with speakers, door prizes, and refreshments. Seed swaps can be a vehicle to teach others how to save seed, the importance of seed diversity, heirloom seeds, and other aspects of gardening. Some exchange more than seeds; tables may be set up to collect used gardening books, magazines, tools, pots, and nursery catalogs. Some may expand their definition of seeds and allow bulbs, rhizomes, and cuttings. Others include related activities such as learning to make handmade seed envelopes.

Each seed swap is different but usually organizers have established guidelines for the seed such as the type of container to use, the number of seed in each bag, and the information required on the label. Organizers should clarify if commercial seed packages or hybrid seeds are accepted. Although swaps do not want seeds from invasive plants, the organizers should clarify the definition of an invasive plant in their area.

If you are interested in attending a seed swap, ask your local county extension agent or Master Gardeners if they know of seed swaps in your area. Check out my monthly list of local gardening events at pegplant.com for seed swaps in the Washington DC metro area.

If you are interested in starting a seed swap, visit a few first to see the range of activities that could take place and the number of volunteers required. Read Seedswap: The Gardener’s Guide to Saving and Swapping Seeds by Josie Jeffery and download the Seed Savers Exchange’s 8-page handout on how to organize a seed swap. To learn how to save seeds, read my article entitled “How to Save Seeds from the Home Garden.” Happy #seedswapday!

Subscribe Now to Pegplant’s Post for a Chance to Win David Austin English Rose

One of David Austin’s English roses in the landscape. Photo courtesy of David Austin Roses.

Enter your e-mail here to subscribe to Pegplant’s Post, an e-newsletter about gardening in the Washington DC metropolitan area. This free monthly communication lists 50 to 100 local gardening events, recently published gardening books, and articles and tips specific to this immediate area. Each issue also features the opportunity to win a free plant or gardening product. For the upcoming February 2020 Pegplant’s Post, one lucky subscriber will win a bare root English rose, courtesy of David Austin Roses.

A David Austin English rose needs no introduction. David Austin is one of the greatest rosarians and rose breeders in the world and the first to create a horticultural brand. In the early 1950s, David Austin began to create a more beautiful rose by combining the fragrance of old roses with the color range and repeat flowering habits of the modern roses. In 1961, he released his first commercial English rose, ‘Constance Spry’. Since then he has released more than 200 English roses. English roses are fragrant with many petals, creating a lush, full flower. The plants are disease resistant and bloom all season long.  The David Austin representative will work with the winner to determine the correct time for shipping and planting and to answer any questions about roses.

It All Started With Seeds

Saving various types of lima beans and their names and stories

I read a phrase that is so true: “It all starts with the seed. The seeds take care of us.” We rely on seeds, thus plants, to feed, clothe, and shelter us. But these seeds in turn rely on us. Our cultivated plants (not wild grown but grown in gardens and farms) depend on human care. If we do not preserve a species it will become extinct. If no one grows a plant and saves the seed, the plant and its genetic material will not exist anymore.

The Importance of Seeds

Because seeds are fundamentally important to our survival, saving seeds, especially open pollinated, heirloom seeds, is vital. Plants make up 80 percent of our diet. On an agricultural level, saving seeds preserves genetic diversity. Breeders can tap into a large genetic pool for improved crops and pest/disease resistant crops. Saving seeds of various plants ensures crop diversity so that one pest/disease does not wipe out one crop. Saving seeds of plants that have adapted to a local area helps to become resilient to climate change.

Sharing saved seeds at a seed swap

On a home gardener level, saving seeds saves money. One can exchange seeds at seed swaps or pass down seeds to future generations. Over time, saving seed from plants that have done well in the garden saves plants that have adapted well to the region. This may help with climatic change. Saving seed also increases the diversity of plants grown. There is more of a choice, more of a variety to choose from for better flavor, time of harvest, or plant type. Saving seeds also saves the memories and stories from previous generations and the lineage of heirlooms.

However, each year, as seed are not saved, plants become extinct. According to the United Nations Food and Agriculture Organization, an estimated 75 percent of global food diversity has become extinct in the past 100 years. Of just 20 plants used for global food production in 2014, only 9 accounted for more than 66 percent of all crop production. Only five cereal grains make up 60 percent of our calories. In the past century we have lost more than 90 percent of our seed diversity. Thousands of plant species are no longer available, and we continue to lose them every day. Yet biodiversity is essential to food and agriculture and provides us and plants with resilience.

Seed Saving Initiatives

Grandpa Ott’s morning glory

Fortunately, there are seed saving initiatives across the world to save seeds for future generations. One American organization, Seed Savers Exchange, has several programs that are extremely useful and helpful to home gardeners. Seed Savers Exchange (SSE) began in 1975 by Diane Ott Whealy and Kent Whealy. Diane’s grandfather gave them seeds of Grandpa Ott’s morning glory and German Pink tomato which were brought by Grandpa Ott’s parents from Bavaria when they immigrated to Iowa in the 1870’s. Diane knew that with her grandfather’s passing, unless the seed were grown and saved, they would be lost. She reached out to like-minded people interested in saving and sharing heirloom seeds and gradually formed a network.

Seed Savers Exchange

German Pink tomato

Today, SSE is a non-profit organization in Decorah, Iowa, with more than 13,000 members. Its mission is to “conserve and promote America’s culturally diverse but endangered garden and food crop heritage for future generations by collecting, growing, and sharing heirloom seeds and plants.”

The SSE maintains a seed bank with 18,000 to 20,000 varieties at their headquarters in Iowa. They also send seed to the U.S. Department of Agriculture (USDA) seed vault at Fort Collins, Colorado, and the Svalbard Global Seed Vault in Norway.

“At SSE, we store seeds at zero degrees Fahrenheit and 20 percent humidity. Under these conditions, certain seed can last up to 100 years,” said Philip Kauth, Ph.D., Director of Preservation.

To give an idea of the number of varieties that can exist within one plant, Philip said that currently the SSE collection has 6,000 tomatoes. There are 3,000 types on the market that are commercially available. “We have 1,100 varieties of corn but the USDA has 20,000 varieties of corn. We also have 6,000 varieties of beans.” What makes SSE unique is that they also maintain the seed’s history. “We put a lot of emphasis on stories. We preserve the varieties and their histories as well as evaluation data on their performance as a plant.”

The Seed Exchange

Anyone, including home gardeners, may access some of these varieties through the Seed Exchange. The Seed Exchange is a free online database of seeds, basically a seed swap. Anyone can offer or obtain open pollinated seeds to grow in their garden. It does not cost money to view this database; however, in order to list or request seed a free account must be established. If reading hard copy is preferable, there is an annual catalog called the Yearbook that can be ordered for a fee. The Seed Exchange has more than 11,000 varieties of homegrown, open pollinated vegetable, flower, and herb seed. Once people obtain and grow these, they can save and re-sow the seed (hence have them for a long time) or even save and share the seed with friends and family. The Seed Exchange also includes potato tubers, garlic bulbs, apple tree cuttings, and other non-seed material.

Field crew harvesting beans

Today, a quick look at the Seed Exchange reveals 9,563 varieties of tomatoes. Some entries have short descriptions, some long, and some have photos. For example, the description for the Silvery Fir Tree tomato is a “compact (18 – 24 inches high) with unusual, delicate, lacy leaves. In Russian, it is called ‘Serebristaya El’ .. it is an old Russian variety that was introduced to American seed savers in the early 1990s by Marina Danilenko, pioneering private seed seller from Moscow during the Perestroika-era.”

There are 38 entries for spinach including a broad leaved prickly seed spinach “described by Albertus Magnus, a Catholic saint from Germany, in 1260, has been commercially available in the US since at least 1806, and was planted by Thomas Jefferson at Monticello in 1809 and 1812.”

SSE also sells seed, people can order online and from a free catalog. SSE makes about 600 varieties available commercially to the public when inventory of seed is high enough to meed the demand. The revenue from the seed sales, as well as donations and memberships, maintain the organization’s seed collection and promote and encourage the tradition of saving and sharing seed.

Trial beds at Heritage Farm

Seed Savers Exchange Projects

Other interesting SSE projects are Seed Rematriation (identifying and growing plants grown by indigenous communities in order to obtain and save the seeds); SeedLinked, a seed data platform connecting people with information on varieties from other gardeners/farmers; and the Community Seed Network, which engages hundreds of people across the United States and Canada to connect, share, and learn about seeds. The SSE also provides free seed to schools, community groups, and people in need via the Herman’s Garden and Disaster Relief Seed Donation programs.

Heritage Farm

The SSE is a destination point — hundreds of gardeners, horticulturists, and seed savers visit the headquarters, known as Heritage Farm, each year. The public is encouraged to visit the Lillian Goldman Visitors Center and Gift and Garden store, walk through display gardens, including an apple orchard with 900 varieties of apple trees, and attend events such as a seed swap, an heirloom plant sale, a seed school, a tomato tasting, and a harvest festival. And if that isn’t enough, there is always the Robert Becker Memorial Library with 6,000 volumes covering agriculture, horticulture, and biodiversity. And to think it all started with seeds of a morning glory and a tomato.

All photos courtesy of Seed Savers Exchange

Celebrate National Hot Tea Day with Lemon Balm

lemon_balm (2)Out of all the herbal teas, lemon balm tea taste most like black tea, without the caffeine. I use the leaves for hot or iced tea either alone or as a base to which I add more pronounced fruity flavors from other plants. In the spring and summer, I pick the leaves as I need them or shear the entire plant down.  The plant revives quickly and a second shearing can be done before the fall. The leaves dry well so I can make lemon balm tea all year round.

One of the easiest herbs to grow, lemon balm is a perennial bush grown for its lemon scented leaves. Lemon balm thrives in morning sun and afternoon shade in my Virginia garden. Hardy to zone 4, lemon balm co-exists well with other plants in the garden, serving as a beautiful green “landscape edible” but also as a pollinator plant. Its botanical name, Melissa officinalis, refers to the bee attracting white flowers (“Melissa” is Greek for “bee”) and long-serving medicinal qualities (“officinalis” refers to historical medicinal value). Actually, lemon balm’s medicinal value has been known for more than 2,000 years but for my family I tend to focus on lemon balm’s culinary uses. Fresh leaves add lemon flavor in baked goods like pound cake, muffins, scones, and cookies. Lemon balm can also be added to fruit salad, sorbets, butter, cheese, fish, and chicken dishes.

Lemon balm is easy to grow from seed but also cheap to buy as a small plant in the spring. If a friend has it, get a stem cutting and root it in water. As a member of the mint family, lemon balm roots easily but this species is not invasive. Try growing lemon balm to brew a hot cup of tea to celebrate National Hot Tea Day!

Visit the Philadelphia Flower Show on Opening Day!

This year the theme for the annual Philadelphia Flower Show is Riviera Holiday. In the past I have written articles about the show and the local nurseries and private organizations that host chartered bus trips. Taking a luxury bus is a great way to attend, no need to worry about traffic and parking. This year, there is a new trip so you can attend the first day, Saturday, February 29 (the show runs until March 8).

Teri Speight, owner of garden website Cottage In the Court, has reserved a bus departing from the lower parking lot of the District Heights Municipal Building, District Heights, MD. The bus departs at 8:00 am and returns by 9:00 pm. A native Washingtonian, Teri is a garden blogger, garden visionary, and a great garden speaker. For more information, contact Teri directly. The reservations deadline is Tuesday, January 14, 2020. Call at (301) 785-7507 or e-mail at teri@cottageinthecourt.com.

Each year the Philadelphia Flower show has a different theme and this year Riviera Holiday is inspired by the world’s exotic Mediterranean gardens. What a great break this will be from our cold, dreary winter! According to the flower show’s website, “groves of citrus trees lead the way providing a lush dramatic promenade to the sunshine drenched landscape ahead. Breathe in fragrant waves of lavender inspired by the terraced gardens of Monaco. Drifts of purple and white spiked salvias, specimen succulents, and an intoxicating variety of scented geraniums, roses, rosemary, and sage create a stunning mosaic that is at once picturesque and charming.”

Who could resist?

Celebrate Houseplant Appreciation Day

Small Arrowhead Plant

Today, January 10, 2020, is Houseplant Appreciation Day. Here are five low-light, low-maintenance houseplants that are easy to find at local garden centers. Houseplants should be appreciated — they have a lot to offer us.  Houseplants improve air quality by removing chemicals and carbon dioxide and supplying oxygen. Houseplants provide a positive psychological impact by increasing memory retention and concentration and reducing stress. When you choose the right plant, it can add beauty and color. Try growing these in your home or office.

ZZ Plant

ZZ Plant

The ZZ plant (Zamioculcas zamiifolia) is native to eastern Africa. The unusual botanical name comes from the cycad genus Zamia because the foliage is similar to cycads and culcas, the Arabic name for elephant’s ear plant (Colocasia). The pinnate glossy, dark green leaves are about a foot long with 6-8 pairs of leaflets, about 3 to 6 inches long, spaced in such a manner that they look like a ladder.

The plant can grow to a few feet tall so it is not a desktop plant. However, if you buy several and plant in a row, they make a distinctive “screen.” The roots are actually swollen rhizomes, which means the plant can tolerate very dry conditions. Although ZZ plants are not grown for flowers, they do bloom at the base of the plant with peace lily type flowers.

Chinese Evergreen

Chinese Evergreen

Chinese evergreen (Aglaonema spp.) plants vary in color and size. Although it is an upright plant that grows to a foot or two, it is possible to purchase a young one for the desk. There are plants with variegated green and cream leaves or green and silver leaves, and there is a new variety called red aglaonema with red, pink, and green leaves. Chinese evergreen plants are very hardy, tolerant of a wide range of conditions.

Arrowhead Plant

Like the name suggests, arrowhead plants (Syngonium spp.) have arrow-shaped leaves. They are often sold as small plants for terrariums. Mature plants are about a foot tall. The leaves usually are white and green but there are gold and green varieties and plants with a blush of pink.  As the plant matures, the leaf shape and color changes so that mature leaves can be all green.

Arrowhead with Pink Blush

Snake Plant

Snake Plant

Most snake plants (Sansevieria spp.) have foot-long, sword-shaped leaves. The leaf color is usually a mottled green, with yellow, gray or silver margins. There are varieties with more yellow or silver coloring in the leaves. There are varieties that are short, almost stunted looking and there are some with very thin, cylindrical leaves. Snake plants provide a strong vertical interest, making them good floor plants.

Devil’s Ivy or Golden Pothos

Devil’s ivy or golden pothos (Scindapsus spp.) has heart-shaped leaves with green and yellow or green and white variegation. There are golden varieties as well. In the tropics, this plant grows as a vine so the plant has a natural trailing or cascading effect when grown indoors. It is a good plant to place high up on shelves so the stems can be allowed to cascade down. Cuttings of the stems root very easily, making it a great plant to share with friends or grow in a vase of water.

White and Green Variegated Pothos

Golden Pothos

New Downy Mildew Resistant Basil Plants on the Market

Devotion Basil

Basil lovers are in luck this year. There are four new sweet basil varieties that are resistant to downy mildew. Downy mildew disease has affected basil for a decade now, destroying the leaves so much that gardeners have to throw away their infected basil plants.

The four new downy mildew resistant (DMR) basils developed by Rutgers University are Rutgers Devotion DMR, Rutgers Obsession DMR, Rutgers Passion DMR, and Rutgers Thunderstruck DMR.

Downy mildew disease was first reported in Florida in October 2007. It has since spread to field-grown and home-grown plants across the country. The disease appears as yellow leaves and a gray cotton appearance under the leaves (the spores). There is no treatment since these plants were meant to be eaten. Gardeners must throw the plants away at first sign to prevent infection of other plants.

Sweet basil has been more susceptible to the disease than Thai, lemon, lime, and the spice types of basil. This suggests that these other basils are genetically resistant to downy mildew. Researchers at Rutgers spent many years crossing sweet basil with these plants in order to provide the sweet basil with the same resistant genetic makeup. These basils were developed through traditional crossbreeding efforts, not genetic engineering. The four Rutger varieties still look, grow, and taste like sweet basil and can be grown in the garden or in containers. There is the possibility that home gardeners may see some disease spores under the leaves and yellow discoloration on the upper side but all they must do is snip off these leaves. The entire plant does not have to be thrown out.

Obsession Basil

Basil is an annual herb, easily grown from seed. In the Washington DC metro area, start growing basil outside after the last frost, usually mid-May. Basil likes full sun, warmth, and well-drained soil. The plants can benefit from fertilizer mid-summer especially if they are being harvested often. Basil should be harvested or pruned to encourage branching and more foliage and to prevent flowering. Home gardeners can find the Rutgers Devotion DMR and Rutgers Obsession DMR from Johnny’s Selected Seeds, High Mowing Organic Seeds, and Stokes Seeds.

Photos courtesy of Rutgers’ New Jersey Agricultural Experiment Station.

Local Resources for Gardeners Interested in Culinary Herbs

According to the Herb Society of America, herbs are “plants (trees, shrubs, vines, perennials, biennials, or annuals) valued historically, presently, or potentially for their flavor, fragrance, medicinal qualities, insecticidal qualities, economic or industrial use, or in the case of dyes, for the coloring material they provide.” I am particularly interested in “plants valued for their flavor,” i.e., culinary herbs. This is a work-in-progress guide to culinary herbs resources in the Washington DC metropolitan area.

The following are the local public herb gardens, sources for buying herbs, societies, magazines, and books. The asterisk indicates that the locations listed also offer herb events, classes, and workshops. This is not all inclusive, there are other groups and businesses such as master gardeners and nurseries that provide herbal presentations. These are listed on my local monthly events tab on pegplant.com.

Public Herb Gardens

National Herb Garden, U.S. National Arboretum, Washington DC*

National Library of Medicine’s Herb Garden, Bethesda, Maryland

Green Spring Gardens (Potomac Unit donated the Doris Frost Herb Garden in 1995), Alexandria, Virginia*

Meadowlark Botanical Garden’s Herb Garden, Vienna, Virginia*

U.S. Botanic Garden and the Bartholdi Park, Washington DC*

The Bishops Garden at the National Cathedral, Washington DC.

The Franciscan Monastery’s garden, Washington DC (annual plant and herb sale in April)

The Green Farmacy Garden, Fulton, MD*

Plant and Seed Sources

See pegplant.com for a list of nurseries and a list of seed sources. Most local nurseries sell herbs in the spring. Two nurseries that specialize in herbs are Debaggio’s Herb Farm and Nursery in Chantilly, VA, which is only open from spring to mid-summer; and Willow Oak Flower and Herb Garden* in Severn, MD.

The Potomac Unit of the Herb Society of America sells herbs at the Friends of the National Arboretum plant sale at the U.S. National Arboretum in DC, in April.

The Franciscan Monastery has an herb and plant sale in April.

The Baltimore Herb Festival is in May at the Leakin Park, Baltimore, MD.

Blooming Hill Lavender Farm specializes in lavender and has an annual lavender festival in June as well as other herb-related events throughout the year, Purceville, VA.*

Smile Herb Shop, College Park, MD.*

Societies

The Herb Society of America, Ohio. The website has many resources and a library of webinars.

The Potomac Unit of the Herb Society of America is the local unit for the Washington DC metro area. There is a membership form on the website or come to a meeting as a guest.

Magazines

The Essential Herbal magazine (a website, blog, magazine).

Herb Companion was bought by Mother Earth Living which keeps the content on their website. Herb Quarterly, can subscribe or buy at Barnes & Noble.

Culinary Herb Books, chronological order

Botanical Baking: Contemporary Baking and Cake Decorating with Edible Flowers and Herbs by Juliet Sear, 2019

The Herbalist’s Healing Kitchen: Using the Power of Food to Cook Your Way to Better Health by Devon Young, 2019

The Kitchen Herb Garden: Growing and Preparing Essential Herbs by Rosalind Creasy, 2019

Grow Your Own Herbs: The 40 Best Culinary Varieties for Home Gardens by Susan Belsinger and Arthur O. Tucker, 2019

Beyond Rosemary, Basil and Thyme: Unusual, Interesting and Uncommon Herbs to Enjoy by Theresa Mieseler, 2019

The Herbal Kitchen: Bringing Lasting Health to You and Your Family with 50 Easy-to-Find Common Herbs and Over 250 Recipes by Kami McBride, 2019

A Taste for Herbs: Your Guide to Seasoning, Mixes and Blends from the Herb Lover’s Garden by Sue Goetz, 2019

Herbal Handbook for the Homesteaders: Farmed and Foraged Herbal Remedies and Recipes by Abby Artemisia, 2019

The Art of Edible Flowers: Recipes and Ideas for Floral Salads, Drinks, Desserts and More by Rebecca Sullivan, 2018

The Herbalist’s Kitchen: Cooking and Healing with Herbs by Pat Crocker, 2018

The Homesteader’s Herbal Companion: The Ultimate Guide to Growing, Preserving and Using Herbs by Amy K. Fewell, 2018

The Art of Cooking with Lavender by Nancy Baggett, 2016

The Culinary Herbal: Growing and Preserving 97 Flavorful Herbs by Susan Belsinger and Arthur O. Tucker, 2016

Homegrown Herb Garden: A Guide to Growing and Culinary Uses by Lisa Baker Morgan and Ann McCormick, 2015

Cooking with Flowers: Sweet and Savory Recipes with Rose Petals, Lilacs, Lavender and Other Edible Flowers by Miche Bacher and Miana Jun, 2013

Edible Flowers: 25 Recipes and an A-Z Pictorial Directory of Culinary Flora by Kathy Brown, 2012

Eat Your Roses: … Pansies, Lavender and 49 other Delicious Edible Flowers by Denise Schreiber, 2011

Essential Guide to Growing and Cooking with Herbs by Herb Society of America, edited by Katherine K. Schlosser, 2007

The Edible Flower Garden by Kathy Brown, 1999

Edible Flower Garden by Rosalind Creasy, 1999

Edible Flowers: Desserts and Drinks by Cathy Wilkinson Barash, 1997

Living with Herbs: A Treasury of Useful Plants for the Home and Garden by Jo Ann Gardner 1997

Edible Flowers: From Garden to Palate by Cathy Wilkinson Barash, paperback 1995; hardback 1993

Herbal Treasures: Inspiring Month-by-Month Projects for Gardening, Cooking and Crafts by Phyllis Shaudys, 1990

Rodale’s Illustrated Encyclopedia of Herbs, edited by Claire Kowalchik and William H. Hylton, 1987

The Pleasure of Herbs: A Month-by-Month Guide to Growing, Using and Enjoying Herbs by Phyllis Shaudys, 1986

Pegplant’s Post: Gardening E-Newsletter for DC Metro Area

Enter your e-mail here to subscribe to Pegplant’s Post, an e-newsletter about gardening in the Washington DC metropolitan area. This free monthly communication lists 50 to 100 local gardening events, recently published gardening books, and articles and tips specific to this immediate area. Each issue also features the opportunity to win a free plant or gardening product. For the upcoming January 2020 Pegplant’s Post, one lucky subscriber will win one Plantskydd quart bottle of a spray liquid that repels deer, rabbits, and voles and a one-pound granular repellent for rabbits, squirrels, and voles. If you are not already a subscriber, subscribe now for the opportunity to win these two products!

Plantskydd is a family of organic repellent products for gardeners as well as professional horticulturists to use to prevent damage to plants and gardens. The products are organic, made from porcine or bovine dried blood which has an offensive odor. The products can also be used to mask a sweet smell as mentioned in my October 2019 article on planting spring blooming bulbs. Soak the bulbs in Plantskydd so animals do not detect them and dig them up. Plantskydd repellents are safe for vegetable gardens and are rain and snow resistant so no need to constantly re-apply. Made in the United States, Plantskydd products can be ordered from their website or purchased at independent garden centers.

Best Helenium Plants for the Mid-Atlantic Area

Kanaria, top rated, with good powdery mildew resistance and a pollinator favorite

The Mt. Cuba Center has just published Helenium for the Mid-Atlantic Region, a 16-page report detailing the results of a 3-year trial of 44 taxa of Helenium plants. A member of the Aster family, the genus Helenium has summer to fall-blooming perennials with daisy-like flowers about 2 inches across. The flowers are in various colors of yellow, orange, and red, with raised yellow to brown centers, making them look like buttons.

The flowers are beautiful, but the plants are not commonly found in American gardens. Part of this may be because its common name “sneezeweed” leads people to erroneously assume the flowers cause allergies. In fact, the flowers are pollinated by insects, not wind. Sneezeweed is finely ground plant parts that are inhaled, like tobacco snuff. Part of the unpopularity may also be the plant’s tendency to flop over, exhibit powdery mildew, and/or contract a disease called aster yellows. Although they require full to partial sun, they are not drought tolerant and native plants are found growing in wet areas.

When asked why this genus was chosen for the trial garden, Sam Hoadley, Mt. Cuba Center’s Horticultural Research Manager, answered: “Helenium really is a genus that is native to the Americas, and there are several species native to the eastern United States. They are really not well represented in American horticulture. I think, outside of the native plant communities that will work with Helenium autumnale and Helenium flexuosum, we felt that this [trial] represents a fairly diverse group of plants and deserves a second look in American horticulture after it’s been so popular in Europe to see how these plants perform there. We also knew that they have significant benefits for bees and wasps, anecdotally. We really wanted to see how these plants would perform and what benefits or attraction they would have for these pollinators when brought back to the United States.”

Zimbelstern, second top rated, pollinator favorite, excellent powdery mildew resistance

Heleniums are popular in European gardens where extensive breeding has been done in Germany and the Netherlands. German breeders Karl Foerster, Gustav Deutschmann, Peter zur Linden and Dutch breeders Inez Arnold and Bonne Ruys have cultivated many Heleniums for exquisite flower colors, shorter forms, and increased resistance to drought. Karl Foerster in particular created more than 70 cultivars drawing on two native American species: H. bigelovii, which is found in Southern Oregon, California, and Arizona; and H. autumnale, which is found across the country. These plus a third species that is found in the eastern United States, H. flexuosum, were included in the trial.

“They really contribute some great late-season interest,” said Sam. “They are in bloom when gardens are in a lull, right at the end of summer and the beginning of fall, bridging a gap in the garden. There’s been a lot of Helenium breeding so that size, stature, and habit of the plant are becoming more and more diverse. For that reason, you are able to incorporate it into more garden designs.”

H. autumnale, a native species that is most visited by bees and wasps

In the trial at the Mt. Cuba Center in Delaware, forty-four taxa including three species were grown in full sun on clay-loam soil. By the beginning of the third or final year, only one-third of the original 220 plants remained. Plants were given minimal care although staff did try to prevent the flop with the Chelsea Chop and several staking methods on some plants to see which would work. Plants were watered during the first year for establishment and during any extremely dry periods. They were not sprayed with fungicides. Many plants succumbed to dry soil, powdery mildew, aster yellows, and possibly poor winter hardiness.

The downloadable report has three tables:  performance summary ratings and plants characteristics, plants that did not complete the trial, and best Heleniums for bees and wasps. Plants are rated on a scale of five (excellent) to 1 (very poor) and include a variety of criteria. None received a five but the top rated, Kanaria, is 4.3, followed by Flammenspiel and Zimbelstern at 4.2, Can Can at 4.1, H. flexuosum at 4.0, and H. autumnale at 3.9. The Mt. Cuba Center’s Pollinator Watch Team observed the plants and found that bees and wasps preferred H. autumnale followed by Zimbelstern, Kanaria, Can Can, and Tijuana Brass.

Can Can, one of top 4 rated, excellent powdery mildew resistance, and a pollinator favorite

Since 2002, the Mt. Cuba Center trial garden has been evaluating native plants and their related cultivars for their horticultural and ecological value. See their website for past reports on phlox, monarda, baptisia, coreopsis, heuchera, echinacea, and asters.

All photos courtesy of Mt. Cuba Center.