Category Archives: Events

Darling Diva Dahlias

Like chrysanthemums, many people associate dahlias with the fall but dahlias can bloom from the beginning of summer to frost. Dahlia flowers are available in a wide range of sizes, colors, and shapes. Each bloom can be 2 inches across to more than 10 inches, in all colors except blue. Plants can reach one to 6 feet tall. Some plants have beautiful dark foliage instead of green leaves. Although there are 40 plus species there are thousands of cultivars. In addition, there are numerous forms such as the single, peony, anemone, collerette, star or single orchid, double orchid, cactus, waterlily, ball, and pompom.

Planting Tubers or Seed

To grow dahlias, you can either purchase tubers or start them from seed. If you purchase a tuber that is a named variety you will know exactly what the plant will look like. Plus, if you purchase cultivars that have been trialed and proven to do well in this area, you will have a good chance of success.  Seed is cheaper than tubers but there is a lot of variability with plant vigor and flower color. Although the seed will grow and produce a plant with pretty flowers for the garden, the flowers may not be exhibition quality.

Tubers can be planted outside in the ground after the average last frost date (Mother’s Day in the Washington DC metro area). Tubers also can be started indoors in April in containers under fluorescent lights or by the window to initiate growth. Seed should be started indoors under lights because planting seed in cold soil may retard the germination rate. Starting seed outdoors in May will only delay the time to reach blooming stage.

Caring for Dahlias

“Put the tuber in a four-inch hole and cover so that it is just peeking through. This way you can see the growth. When it grows, add more soil,” advises John Spangenberg, member of the National Capital Dahlia Society and owner of Crazy 4 Dahlias. John is a long time dahlia enthusiast who also sells tubers from his website.

Growing a dahlia plant is similar to growing a tomato plant: full sun and plenty of water and food. A dahlia can grow in less than 6 hours of sun but would not produce as many flowers. After planting the tubers, insert stakes such as tomato cages or posts. In the beginning, dahlias will require plenty of water, generally one inch of water per week. Dahlias are heavy feeders and will need fertilizer throughout the summer. Slow release fertilizers also work well. Dahlias appreciate a leaf or straw mulch to keep the tubers cool and to prevent weeds.

Encouraging More Flowers

In the beginning of the growing season, John recommends topping the plants to encourage bushier, sturdier plants with more flowers. The center bud (not flower bud but central growth) should be pinched back. “When you see three to four sets (or pairs) of leaves, break the center top off,” explained John.

Later in the season when flower buds appear, disbud or cut off smaller, lateral flower buds to encourage the top bud to form a single, larger flower. When a dahlia flowers, there are three stems with three buds in a v-shape. When the outer two smaller buds are the size of peas they should be cut leaving the center flower bud.

“The more you cut your flowers, the more flowers you get,” said John. If you don’t cut a flower for a vase, make sure you at least deadhead them. Deadheading is cutting off and disposing flowers that are past their prime to encourage the plant to produce more flowers.

Throughout the season, make sure the plant is well staked as it grows, feed it, and make sure it gets enough water.

Saving Tubers in the Fall

Dahlias are native to Mexico. Here in Washington DC they are treated as tender perennials and may or may not come back the following year. In order to ensure that the plants can be grown again next year, most gardeners lift and store the tubers in October.

“In the fall when get the first frost, cut the plant a couple of inches above the ground and let sit for a week or dig them up,” explained John. “You want to have the eyes develop and swell to be able to see them well. It helps to see the eyes when dividing the tubers. You can divide in the spring or fall but it is easier to divide in the fall.”

Dahlia tubers are swollen roots. Each tuber has to have an “eye,” which is a growing point in order to grow. From that eye the stem will emerge. In May, a single tuber with an eye is planted for a single plant. In the fall, when the plant is lifted out of the ground, there will be more new tubers joined together in an area called the crown. The “eyes,” or viable growing points, are in the crown. This can be stored as is or divided to create more plants.

John uses vermiculite in a box to store his tubers but there are many methods to store tubers. He finds vermiculite works best because it absorbs and releases moisture. Tubers should be in the coolest place in the house where there is constant temperature such as a crawl space or basement or a closet next to the outer wall of the house.

Because they are native to Mexico, one would think that dahlias would be easy to grow here with our sunny, warm summers. In fact, dahlias are native to a mountainous region in Mexico with more wind, less humidity, and cooler temperatures. Thus dahlias grow very well in the Pacific Northwest but have some difficulty in the mid-Atlantic. They need quite a bit of water, yet as heavy feeders, the rain can leach the nutrients. Plus the humidity can encourage disease. “In this area, we have issues with slugs, earwigs, rabbits, groundhogs, and deer,” said John. “Plus we have noticed that Japanese beetles prefer white and yellow flowered dahlias.”

Selecting Dahlias for Washington DC Metro Area

To choose a dahlia that performs well here, look to the National Capital Dahlia Society for recommendations. A branch of the American Dahlia Society (ADS), the National Capital Dahlia Society is comprised of dahlia enthusiasts and breeders who meet on a regular basis. Every year they manage a trial garden at the Agricultural History Park in Derwood, MD. “The display garden is a trial garden to test new introduction from across the country to see how they do here. We look at bloom quality and plant vigor and report this to the American Dahlia Society,” said John. Later in October, the Society members will dig up the dahlias at the trial garden and demonstrate how to save the tubers (open to the public). They also sell tubers next year so if you are interested in growing dahlias that do well in the Washington DC metro area, contact them via their website: http://www.nationalcapitaldahlia.org.

This past weekend, the National Capital Dahlia Society held their annual dahlia show at Brookside Gardens where flowers were judged using the ADS criteria. The photos in this article are dahlias from the Court of Honor, those dahlias that have been selected from all entries for final judging. The video is a scan of the Court of Honor.

American Heritage: Native Paw Paw Trees

Paw paw flowers in the spring

It’s paw paw season! Paw paws (Asimina triloba) are native trees that bear fruit in August, September, and October. Fruit of cultivated trees look very similar to mangos—green, kidney-shaped, and about 6 inches long and 3 inches wide. They have a variety of common names such as Indiana banana, poor man’s banana, and bandango. When cut in half, the interior reveals a yellow, custard-like pulp with two rows of large seeds. Paw paws can weigh from ½ to 1 pound. Technically a berry, they are the largest North American edible fruit. Paw paws taste like a cross between a banana and a mango with a splash of pineapple. They can be eaten raw or used in ice cream, pudding, smoothies, butter (such as apple butter), baked goods like cookies and pies, and even beer, brandy, and wine!

From Florida to Texas, north to New York, and west to Michigan, Illinois, Iowa, and Nebraska, paw paws are native to 26 states and grow as understory trees in hardwood forests near streams and rivers. In the wild, the trees grow to 15 to 30 feet and sucker, creating colonies. Reminiscent of cucumber magnolias, they have foot-long, dark green leaves. Unlike other fruit trees, paw paw trees are not subject to a high level of pests and diseases.

Paw Paws in American History and Folklore

Paw paw trees are part of American history and folklore. Jamestown colonists wrote about them in the 1600s. John Lawson, an Englishman, described them in his travels in the Carolinas in the 1700s. Danielle Boone enjoyed eating them. Members of the Lewis and Clark expedition ate paw paws for pleasure as well as sustenance. George Washington grew paw paw trees at Mount Vernon and ate the fruit as dessert. Thomas Jefferson grew them and sent seeds to his colleagues in Europe.  William Bartram, a naturalist, described the trees in Bartram’s Travels. His father, John Bartram, a botanist, sent seeds to Europe. During the Civil War, soldiers as well as African American slaves collected the fruit in the wild to supplement their meager diets. There is even a popular folk song called “Way Down Yonder in the Paw Paw Patch” about collecting ripe paws paws from the ground and putting them in a basket.

Paw paw fruit develop in clusters

Finding Paw Paw Trees and Fruit

Currently, Washington DC residents can see paw paw trees in the wild along the C&O Canal and Potomac River and as native plant representatives in public gardens. There are paw paw trees at the Smithsonian Pollinator Garden, next to the National Museum of Natural History, and at the U.S. Botanic Garden’s newly renovated Bartholdi Park and their National Garden’s Regional Garden of Mid-Atlantic Native Plants. 

Although paw paws are part of American heritage, you may not find them in grocery stores. When the fruit is ripe enough to eat, it drops to the ground and is highly perishable. The thin skin bruises easily, discoloring to black. Paw paws are best eaten immediately or preserved by removing and freezing the pulp. You may find them at local farmers markets in peak season and you will definitely find them at paw paw events across the country in the fall.

Growing Paw Paws in the Home Landscape

Paw paw fruits can be eaten raw

“There is a paw paw renaissance now,” said Michael Judd, owner of Ecologia, an edible and ecological landscaping service in Frederick, MD. Author of Edible Landscape with a Permaculture Twist, Michael currently is writing a book about paw paws and hosts an annual paw paw festival that will be on September 22 this year at LongCreek Homestead. “I call the paw paw an edible landscape all-stars because the tree is very attractive, low maintenance, and very fruitful.”

As native, hardy trees, paw paws can be grown in typical suburban plots. “Paw paws grow easily here,” said Michael. “This is paw paw country.” Although they are not self-fertile, that is, there must be two trees to cross pollinate to produce fruit, one can trim the trees to fit in residential properties. Michael recommends growing the trees in full sun, 10 to 12 feet apart, and cutting the central leader back to keep the trees at 8 feet. This shorten stature also makes them easier to harvest the fruit. Therefore, homeowners could have two 8-f00t trees in the yard producing 50 pounds of fruit each year. If full sun is not possible, they can grow in part shade but will produce less fruit.

Paw paw trees have a pyramidal shape

Michael recommends purchasing either a grafted tree, a select seedling, or a specific cultivar. Starting from seed takes years to produce fruit. Also starting from a wild paw paw seed will result in less than desirable fruit. The taste of wild paw paws varies plus the fruit is small with a poor pulp to seed ratio.  Breeders spend years selecting desirable characteristics such as large fruit, a high pulp to seed ratio (more pulp, less seed), and good flavor.

You can’t go wrong planting paw paws. They are native, deer resistant trees that provide fruit and pretty yellow fall color. “Paw paw trees are very ornamental, they have a beautiful pyramidal shape,” explained Michael. “The leaves turn to a beautiful yellow golden color in the fall and when the leaves drop they reveal a tree with nice architecture in the winter.”

All photos taken by Michael Judd.

Greenstreet Gardens Sets Up Shop in Belle Haven, Virginia

It’s no mirage–that is a tropical oasis on Richmond Highway. Residents of Belle Haven are noticing a pop of color now that Greenstreet Gardens has moved in.

Ray Greenstreet, owner of Greenstreet Gardens, is leasing the lot at 5905 Richmond Highway, Alexandria, Virginia, as an extension of the Greenstreet Gardens retail operation. Instead of building a new structure, Ray created an open air retail garden center featuring houseplants, perennials, annuals, containers, fertilizer, and gardening tools.

“This location just fell in our lap but it is a great opportunity,” said Ray. Despite the windfall, it took months to get the place into shape for the customers. “This was vacant for a long time, maybe 10 years,” said Ray. “Before we came, it was a VDOT (Virginia Department of Transportation) lot for the Wilson Bridge where they dumped gravel. We had to remove 5 dumpster loads of trash.”

Currently, the cash register is in an open shipping container. The products, from plants to fertilizers, are outside on racks or wooden benches. The fire hydrant on the sidewalk provides the water for the plants, most of which are in full sun.  Although Ray is working to have electricity, lighting is not an issue now with the long day length. Just the inventory alone, lush green foliage and eye-popping flowers, beautifies the neighborhood but Ray intends to enhance the location even more. “We intend to add trees to create a park-like setting,” said Ray. “In the fall we will sell chrysanthemums and pumpkins followed by Christmas trees.” After the holidays, the location will close in January and February and re-open in March.

I visited the corner lot last weekend. A large, tall display of tropical plants in containers marks the entrance to the parking lot, which is quite spacious. There was a wide variety of plants on benches and racks of new plants that had just been delivered. The plants were well watered and healthy and the employees were pleasant and helpful. Because this location is just south of the Beltway on Richmond Highway with plenty of traffic, stop lights, and median strips, I thought it would be difficult to access. It turned out to be easy to get in and out with no problems.  This new location truly provides a new source of greenery to residents on the northern end of Richmond Highway.

A native Marylander, Ray and his wife Stacy started Greenstreet Growers, a greenhouse operation in Lothian, Maryland, in 2000. They then ventured into retail and opened Greenstreet Gardens on 14 acres of their 65-acre farm in Lothian. In 2012, they expanded into Virginia and opened a retail store at 1721 West Braddock Road, Alexandria, which is thriving. Later they opened a smaller store in Del Ray, now closed. The Belle Haven location is the third Virginia location and is open every day of the week from 9:00 am to 5:00 pm. If you are ever in the area, stop by and say hello to our new neighbors!

 

My Podcast Debut on the Vegetable Gardening Show

A week ago Mike Podlesny of the Vegetable Gardening Show interviewed me for his podcast. It is an audio and visual podcast so you can have the pleasure of seeing me talk with him on Show #414: Gardening in the Nation’s Capital for 30 minutes on YouTube or listening to me on Podbean, Stitcher, iTunes, or iHeartRadio.

Mike gardens in New Jersey, manages the Seed of the Month Club, and has authored Vegetable Gardening for the Average Person. We talked about why I started writing gardening articles for magazines and how I designed my website and the services I provide, including the free monthly newsletter. We talked about growing tomatoes, herbs, and potatoes and the gardening challenges we have in common such as minimal space and deer. The podcast was like chatting with the neighbor in the garden, it was a lot of fun. If you have not heard of Mike before, check him out at www.averagepersongardening.com.

New Herban Lifestyles Series of Classes at U.S. National Arboretum

Interested in learning more about herbs? Check out the new Herban Lifestyles series of presentations at the U.S. National Arboretum. This series of presentations is designed to help you learn new ways to incorporate herbs into your everyday life. You can register for all the events or just select particular events. Some are free, some require a fee. Some are in the National Herb Garden while others are in the Visitor Center Classroom at the Arboretum. Below is the list for this year.

Herbal Bitters: Sweeter than You Think!
August 4, 1:00 pm – 4:00 pm
National Herb Garden

Discover the benefits that bitter herbs offer, from jazzing up your favorite cocktail to aiding digestion after a heavy meal. A variety of hand-crafted bitters will be available for tasting. This program is part of the Under the Arbor series and is free. No registration required.

Herbal Salves: They’re the Balm!
August 11, 10:00 am – 12:00 pm
Visitor Center classroom

Learn how to make herb infused oils for use in soothing salves. The healing properties of various oils and herbs will be covered, and participants will get to take home a jar of salve made in class. Fee: $35 ($28 Friends of the National Arboretum (FONA) members). Registration required.

Hot, Hot, Hot! The Secrets of Herbal Aphrodisiacs
August 18, 10:00 am – 12:00 pm
Visitor Center classroom

Herbalist Joan Greeley, owner of Plant Wisdom Within, will instruct participants in the creation of mojo-enhancing herbal concoctions. The weather isn’t the only thing hot this summer! Due to the mature nature of this program, registrants must be at least 18 years old. Fee: $35 ($28 FONA members). Registration required.

Cold Comfort: Herbs to Aid Immunity during Cold and Flu Season
October 20, 10:00 am – 12:00 pm
Visitor Center classroom

Join herbalist Whitney Palacios as she teaches participants how to make syrups, teas, and other herbal preparations that fortify and nourish the immune system during the winter months. Fee: $35 ($28 FONA members). Registration required.

Herbs – They Make Scents!
October 27, 10:00 am – 12:00 pm
Visitor Center classroom

Learn how to harvest and prepare herbs to create fragrant herbal incense cones and powders. Participants will create their own blend to take home. Please bring a small container to safely transport your freshly made incense. Fee: $35 ($28 FONA members). Registration required.

Additional herb presentations by Herb Society of America units:

Under the Arbor: Lemon Herbs
September 8, 1:00 pm – 4:00 pm
National Herb Garden

A refreshing drink on an early autumn day. Tasty citrus cookies after a light lunch. What could be better? Discover how the South Jersey Unit of the Herb Society of America creatively incorporates lemon-flavored herbs into every day culinary fare. Free, drop-in, no registration required.

Under the Arbor: Chile Pepper Celebration
October 6, 1:00 pm – 4:00 pm
National Herb Garden

The weather may be cooling down, but the National Herb Garden will turn up the heat during its annual Chile Pepper Celebration. Join Herb Society of America members and National Herb Garden staff as they present chile peppers at their finest. Experience the fire with colorful varieties that don’t hold back! Free, drop-in, no registration required.

Under the Arbor at the National Herb Garden, U.S. National Arboretum

Happy Independence Day!

Day Trip: Visit a Public Garden This Summer

Summer is the time for traveling, exploring, and spending time with family. Thinking of where to go? Consider public gardens and arboreta. Many of these are historic places as well, great for teaching your kids. On my website, pegplant.com, I list gardening books written specifically for the Washington DC metro area. Several of these books, copied and pasted below, are resources listing botanical, public, or historic gardens in east coast states. Check out these books from your local library and plan a day trip with the family. Enjoy your summer!

  • Maryland’s Public Gardens and Parks by Barbara Glickman, Schiffer Publishers, 2015
  • Capital Splendor: Parks and Gardens of Washington DC by Valerie Brown, Barbara Glickman Countryman Press, 2012
  • A Guide to Smithsonian Gardens by Carole Otteson, Smithsonian Books, 2011
  • Historic Virginia Gardens: Preservation Work of the Garden Club of Virginia by Margaret Page Bemiss, University of Virginia Press, 2009
  • Virginia’s Historic Homes and Gardens by Pat Blackley and Chuck Blackley, Voyageur Press, 2009
  • Garden Walks in the Southeast: Beautiful Gardens from Washington to the Gulf Coast by Marina Harrison, Lucy Rosenfeld, Rowman and Littlefield Publishers, 2006
  • Garden Walks in the Mid-Atlantic States: Beautiful Gardens from New York to Washington DC by Marina Harrison, Lucy Rosenfeld, Rowman and Littlefield Publishers, 2005
  • The American Horticultural Society Guide to American Public Gardens and Arboreta:  Gardens Across America, Volume 1, East of the Mississippi by Thomas S. Spencer and John J. Russell, Taylor Trade Publishing, 2005
  • A City of Gardens: Glorious Public Gardens In and Around the Nation’s Capital by Barbara Seeber, Capital Books, 2004
  • Barnes & Noble Complete Illustrated Guidebook to Washington, D.C.’s Public Parks and Gardens, published by Silver Lining Books, 2003
  • Complete Illustrated Guide to Washington DC’s Public Parks and Gardens by Richard Berenson, Silver Lining, 2003

Relax in DC’s Renovated and Sustainable Bartholdi Park

The U.S. Botanic Garden (USBG) has completed the renovation of Bartholdi Park. The new garden is a showcase of sustainable gardening. Created in 1932, Bartholdi Park has served as a demonstration garden for more than 80 years. In 2016, a complete renovation started that also provided the opportunity to increase accessibility, showcase the Sustainable SITES Initiative principles in action, and demonstrate USBG’s commitment to sustainability.

Some of the changes will be noticeable to visitors. For example, most of the plants are native to the mid-Atlantic region. There is an expanded collection of edible plants in permanent and seasonal plantings in a new kitchen garden. Some of the large trees and shrubs were retained while others were placed in other locations in DC. There is more signage and more places to sit and relax. The tables and chairs were made from white oaks that had fallen naturally during a storm. There is a bike rack, additional lamps/lighting, and a water fountain. There will be outside activities such as yoga and nature-in-motion walks. Not so obvious to visitors are structural changes such as using permeable paving and rain gardens to capture rainfall, diverting runoff from D.C.’s combined sewer system. The original soil was saved and then added back with additional compost. Flagstones from previous pathways were salvaged to create new paths.

Bartholdi Park has achieved the SITES gold certification for its sustainability strategies. It is the first project in Washington, DC, to be certified under SITES Version 2. Sites is a comprehensive system for designing, developing, and maintaining sustainable land. The Park serves as a model for communities interested in sustainable gardening landscapes that are accessible and enjoyable by the public.

The story of the renovated Park is shared through new signage in the Park. A new Field Journal, an interactive booklet for young visitors, can be picked up free at the U.S. Botanic Garden’s information desk. Tours of the Park and other activities can be found at www.usbg.gov/programs.

The U.S. Botanic Garden is open to the public, free of charge, every day of the year from 10:00 am to 5:00 pm. The conservatory is at 100 Maryland Avenue SW on the southwest side of the U.S. Capitol. The Bartholdi Park is across the street. All of these photos are courtesy of USBG.

This Week is National Pollinator Week: Learn How to Support Vital Pollinators

This week, June 18 to 24, 2018, is National Pollinator Week. Organizations across the country will host pollinator awareness events.  In Washington DC there are several events this week. Also, you can participate in the Million Pollinator Garden Challenge by making your garden pollinator friendly and registering your garden at the site (free). I just registered my Virginia garden, a typical suburban home, for the Million Pollinator Garden Challenge.

For National Pollinator Week in 2016, I featured an herb a day that attracts pollinators. Marjoram, cilantro, dill, sage, chives, basil and thyme are common culinary herbs that when left to flower will attract bees and butterflies. Day seven, marjoram, provides links to the herbs as well as other pollinator related resources and organizations.

This year I am focusing on a different group of plants that attract pollinators, see my article tomorrow on pegplant.com.

Register to Learn How to Grow and Use 13 Culinary Herbs

On Saturday, June 23, from 10:00 am to 11:30 am, I will teach a class on culinary herbs at Green Spring Gardens. I will discuss 13 herbs, the cultural requirements, culinary uses, and harvesting and preserving methods. This is not a Powerpoint presentation. I will bring the actual plants so you can touch, taste, and smell!  Everyone will receive a handout with herb information and local resources. And, if you know me, you know there will be a giveaway. Someone will go home with an herb plant. Register online for the “Plants and Design: Herbs–A Baker’s Dozen” class at www.fairfaxcounty.gov/parks/parktakes using code 290-387-4801 or call (703) 642-5173. See you on Saturday, June 23.