Category Archives: plants

Baptisia Plants Perform Well in the DC Metro Area

Baptisia ‘Lemon Meringue’ flowers up close

Baptisia, also called false indigo, is a shrub-like plant that does well in our hot and humid summers. Recent breeding efforts have expanded the range of flower colors creating a new look for an old favorite. Continue reading

Free Local Gardening Newsletter, Complete with Giveaway

Enter your e-mail here to subscribe to Pegplant’s Post, an e-newsletter about gardening in the DC metropolitan area. This free monthly communication lists recently published gardening books, 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 May 2020 Pegplant’s Post, one lucky subscriber will receive Heartbreaker, one of the newest varieties in the Hollywood Hibiscus line.

Heartbreaker has orange petals with yellow-gold veining and a white center. He will only get about 3 to 4 feet tall, perfect for containers. He is one of the most recent stars to be introduced in the Hollywood line of tropical hibiscus plants, along with other stars such as Bombshell, Chatty Cathy, and Disco Diva. This award-winning collection grown by J. Berry Nursery features plants that bloom all summer long, unfazed by DC’s hot and humid summers.  Their large, colorful flowers attract pollinators and add a splash of color to the deck, patio, or poolside. My plants always put a smile on my face, they practically cover the foliage with such happy blossoms. The Hollywood Hibiscus line is known for compact, tropical hibiscus plants that produce many flowers per plant, in a wide range of flower colors.  If you are not already a Pegplant’s Post subscriber, type in your e-mail now at pegplant.com for a chance to win one Heartbreaker in a 2-gallon plastic container.

Now is the Time to Pull Weeds!

Spring has sprung and it is time to pull the weeds! By this time, there are many weeds that are flourishing in the garden but hopefully, not yet flowering. Now is the time to pull them before they flower and set seed. Fortunately, now is a good time to eradicate these weeds because the moist soil makes it easier to pull the small plants.

purple deadnettle on left and hairy bittercress on right

purple deadnettle (left) and hairy bittercress (right)

In my garden I have an infestation of hairy bittercress (Cardamine hirsuta). A member of the mustard family, these young’uns appear as small mounds of subdivided leaves, creating a lacy or scalloped appearance. As the plant matures and grows, slender stems arise from the base producing small, white flowers. By late spring, slender seed pods burst open when touched (called “explosive dehiscence”), shooting seeds as far as 3 feet! Also called shotweed, this weed prefers damp conditions and should be removed as soon as possible.

I also have colonies of purple deadnettle, a member of the mint family. Purple deadnettle (Lamium purpureum) is called “dead” nettle because the plant resembles the true nettles (Urtica spp.) but does not sting like a nettle, hence, “dead” nettle. Right now, I can only see young leaves at ground level which makes it hard to identify but in a few months, the striking flower structures will grow tall above the basal leaves and the youngest, smallest leaves at the top will be purple. Tubular-like, purple flowers, typical of the mint family, peep out from under the uppermost leaves.

henbit in foreground and mouse ear chickweed in background

henbit in foreground and mouse ear chickweed in background

A cousin of purple deadnettle, henbit (Lamium amplexicaule), looks similar but does not have the pronounced purple color on the leaves. Purple deadnettle has stalked leaves on the flower stems while henbit does not. The word “amplexicaule” means leaves grasping the stem. The pretty scalloped leaves wrapped around the stem remind me of Queen Elizabeth I with her ruffled collar. Also a member of the mint family, henbit has small pink/purple, tubular like flowers.

Looking like a cross between a dandelion and a thistle, groundsel (Senecio vulgaris) is a member of the sunflower family. Like a dandelion, groundsel has a taproot and the same feathery type of seed head. It is good to pull while young before the tap root gets established. Already the groundsel is beginning to sport yellow flowers, similar to dandelion flowers but smaller. If these are not removed, the groundsel will flower, set seed, and the wind will disperse hundreds of seeds to the rest of my property.

groundsel

groundsel

Two weeds that I do not have in my garden but I have seen in other people’s gardens are common chickweed (Stellaria media) and mouse ear chickweed (Cerastium vulgatum). There are several different types of chickweed, all members of the carnation family. The common chickweed has smooth, small, egg-shaped leaves and is so named because the plant is used as a starter food for baby chicks. The mouse ear chickweed has hairy leaves, slightly larger than the common chickweed, resembling fuzzy mouse ears. Both have tiny, five-petal flowers but the common chickweed is an annual while the mouse ear chickweed is a perennial. These plants have shallow fibrous roots. Their stems spread and crawl and are capable of rooting where the node touches the soil.

common chickweed and mouse ear chickweed

common chickweed and mouse ear chickweed

The garden is not asleep. Get out there now and start pulling before these vast armies of weeds flower and disperse hundreds of seeds!

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.

A Gardener’s Christmas

A Gardener’s Christmas

‘Twas the night before Christmas,
And all through the yard
The branches were bare
And the ground frozen hard;

The roses were dormant
And mulched all around
To protect them from damage
If frost heaves the ground;

The perennials were nestled
All snug in their beds,
While visions of fertilizer
Danced in their heads;

The newly planted shrubs
Had been soaked by a hose
To settle their roots
For a long winter’s doze;

And out on the lawn
The new fallen snow
Protected the roots
Of the grasses below;

When, what to my wondering
Eyes should appear,
But a Prius full of gifts
Of gardening gear;

St. Nick was the driver
A jolly old elf,
And he winked as he said,
“I’m a gardener myself.

I’ve brought new seeds
And light systems, too,
Give them a try
And see how they do.

To eliminate weeding,
I brought bags of mulch
To attract the pollinators,
I have flowers for best results.

To add to your joy,
I’ve plenty of herbs
And ornamental grasses
For your hell strip curb.

For seed planting days,
I’ve a trowel and dibble.
And a roll of wire mesh,
If the rabbits should nibble.

I have the latest books
Plus some gadgets you’ll love;
Plant stakes and frames,
And waterproof gloves.

Here are sharp shears
And a new compost pit
And, for pH detecting,
A soil testing kit.

With these colorful flagstones,
Lay a new garden path.
For the view from your window,
A bird feeder and bath.

And last but not least,
Some well-rotted manure.
A green garden year-round,
These gifts will ensure.

Then, jolly St. Nick
Having emptied his load,
Started his Prius
And took on the road.

And I heard him exclaim
Through the motor’s quiet hum,
“Merry Christmas to all,
And to all a green thumb!”

Written by Peggy Riccio. Merry Christmas from pegplant.com

your online resource for gardening in the Washington DC metro area

Deer-Resistant, Spring-Blooming Bulbs to Plant

Fall is the time to purchase spring-blooming bulbs in the Washington DC metro area. There is a wide variety of choices but if you have a severe deer problem, you may want to plant deer-proof bulbs. I know, you say, there is no such thing as “deer-proof” but with bulbs there are a few that are actually poisonous. I spoke with Brent Heath of Brent and Becky’s Bulbs in Gloucester, VA, who explained the difference between deer-proof and deer-resistant.

“Critter-proof bulbs are poisonous to animals such as deer, rabbits, squirrels, and voles,” Brent said. “Critter-resistant bulbs have some quality that is unpleasant to the critter but if the critter is hungry enough it will eat the plant.” Of the spring-blooming bulbs, the amaryllis family offers three popular critter-proof bulbs that contain lycorine, a poisonous crystalline alkaloid. Somehow critters know about lycorine and stay away from daffodils, snowdrops, and snowflakes. A subsequent article will describe critter-resistant bulbs for gardeners who are not plagued by deer.

Daffodils (Narcissus)

Daffodils are very hardy in this area, they last for years. There is a wide range of daffodils–flowers vary in color, size, shape, and bloom time. In fact, daffodils are categorized in 13 divisions according to the American Daffodil Society. Usually people think of yellow when they think of daffodil flowers but colors range from yellow to white to cream to orange to pink. Plants can be as short 3 inches or as tall as 2 feet. The bloom time varies from January to the end of April.  “The earliest daffodil to bloom is Early Sensation, which blooms in January and February in my area,” said Brent. Because there are early bloomers and late bloomers, you can extend your range of bloom time by a few months.

Drifts of daffodils about to bloom under deciduous trees

Daffodils are usually planted in a mass for a natural look. They blend well with the front garden or landscape but the small ones should be planted up close to the walkway for visibility. The flowers are perfect for floral arrangements so when you buy bulbs consider planting bulbs for flowers in the landscape and flowers for cutting. Daffodils should be planted in a well-drained area with full sun or part shade. Usually bulbs are planted 5-6 inches deep and 6 inches apart but because the size of daffodil bulbs vary this depends on the size of the bulb. The rule of thumb is to plant 2-3 times the width of the bulb. When I asked Brent which daffodils he recommends, he said that the recommended daffodils for this area have a heart symbol next to them in their catalog (which they mail free). There are also several local daffodil clubs and shows if you want to get additional recommendations and see what the flowers look like before buying the bulbs.

Daffodils for landscape as well as cutting

Snowdrops (Galanthus)

Snowdrops are very early bloomers, sometimes as early as January with snow on the ground. They bloom until March and then their thin, green foliage seems to blend into the landscape and disappear. The plants are small, about 6 inches tall, with white pendulous bells of flowers. Usually each flower has six tepals (a modified petal) but there are double-flowering types too. The tepal length plus the green markings on them vary tremendously. Although they are considered common here in the United States, they have achieved cult status in Great Britain where they have been bred since Victorian times. There are thousands of cultivars, some of which are very expensive.

Snowdrops

Because they are small, it is best to plant many in a group. They naturalize well and can be used in rock gardens. They can be grown in full sun but do best in dappled shade or under deciduous trees. Snowdrops tolerate clay soil and black walnut trees. Plant bulbs 4 inches deep and about 2 to 4 inches apart.

Snowflake or summer snowflake (Leucojum)

There are two species of snowflake: Leucojum vernum and Leucojum aestivum. L. vernum blooms in the winter and early spring, at the same time as snowdrops. They are about 8 to 10 inches tall. L. aestivum blooms much later in April and is about 12 to 18 inches tall. A common L. aestivum cultivar is ‘Gravetye Giant’ which is slightly taller with larger flowers.

Leucojum ‘Gravetye Giant’ next to azaleas, photo courtesy of Brent and Becky’s Bulbs

Snowflakes have wide, strap-like foliage and dainty bells of flowers hanging above the green leaves. Each flower is white with green tips. Snowflakes can be grown in full sun or dappled sunlight. It is best to grow them in a drift, along river banks, and under deciduous trees. The L. aestivum in particular is a great companion plant for spring blooming shrubs and perennials in the garden because of its height and bloom time. Snowflakes prefers rich, well-drained soil, and can tolerate moist soil more so than other bulbs. They also can tolerate clay soil and black walnut trees. Plant the bulbs 6 inches deep and about 6 inches apart.

If deer are an issue for you, try these bulbs in the amaryllis family. You can plant them after a hard freeze, usually late October through November. All of these bulbs are easy to find at local independent garden centers or they can be ordered from these bulb companies.

Start Planting Cool Season, Hardy Annuals for Spring Flowers

snapdragons in the spring

Now is the time to start thinking of planting cool season hardy annuals. This is a group of annuals (grow and die in one season) that can survive the winter and thrive in cool spring weather. In the Washington DC metro area, they are planted in the fall and bloom in the spring. They spend the winter getting established so when spring arrives, they are ready to bolt out the door waving their pretty flowers before the warm season summer annuals appear.

Examples of cool season annuals are snapdragons (Antirrhinum majus), calendula (Calendula officinalis), bells of Ireland (Moluccella laevis), delphinium (Delphinium), lisianthus (Eustoma), love in a mist (Nigella), sweet peas (Lathyrus odoratus), sweet William (Dianthus barbatus), and bachelor buttons (Centaurea cyanus). Many of these make great cut flowers.

I credit everything I have learned about cool season hardy annuals to Lisa Mason Ziegler and her book, Cool Flowers: How to Grow and Enjoy Long-Blooming Hardy Annual Flowers Using Cool Weather Techniques.  Lisa manages a commercial cut flower business in Newport News, which is in Zone 7, similar to my Northern Virginia garden. In addition to growing and selling cut flowers, she writes books, gives lectures, provides free videos as well as Facebook Live presentations, and manages a website called The Gardener’s Workshop.

Several years ago I was inspired by her book to plant calendula and snapdragons in the fall. I was starting them in the beginning of the growing season and was not having great success. The weather became too hot before the snapdragons could bloom and the calendula foliage was covered in powdery mildew because of the summer’s heat and humidity. When I tried her method of starting them in the fall, they both bloomed early enough the following spring that I was able to enjoy the calendula flowers before powdery mildew set in and cut many snapdragons for indoor arrangements.

calendula flowers in the spring

This year, I plan to grow sweet peas, which I have not been able to master in the spring. Our springs are just too short to have a long blooming period. I bought a package of Botanical Interests ‘Old Spice Blend’, a fragrant, heirloom blend of various flower colors. Interestingly, sweet peas are deer resistant and attract pollinators but I am going to grow them for indoor flower arrangements so I can enjoy their beautiful, fragrant flowers in the office.

Although Lisa provides specific information for 30 flowers in her book, in general, we should start 6 to 8 weeks before the average first frost. In Northern Virginia, 8 weeks is August 31 and 6 weeks is September 15. She recommends to err on starting later rather than earlier. Some seeds can be sowed directly in the garden while others work well as transplants. Sweet peas can be done either way so I am going to do both as an experiment to see which works better in my garden. I will start half of the seeds indoors under lights and half outdoors, directly in the garden. In order to have transplants large enough to move into the ground around September 15, I would have to start sowing seeds around September 1. Then I can sow the remaining seeds around September 15. September is still a very hot month so I will have to remember to water often. If this works, next year I will post a photo of the sweet peas.

If hardy annuals are something you would like to try, you can catch up by visiting Lisa’s website, listening to her videos, and reading her book. Although she sells seeds and gardening products, you can also purchase seed packets at your local independent garden center. Good luck!

Habanada: A New Habanero Without the Heat

As a professional garden communicator I receive plants from nurseries to trial in my Virginia garden. I grow them to see how well they perform in our hot and humid summers, our mild winters, and with our own particular population of insects and diseases. Frequently I am growing plants that I would not have even looked at in a garden center. This year I grew something new to me and a game changer for gardeners as well as chefs: Habanada.

Burpee sent me a Roulette “sweet habanero” pepper plant. I have heard of habanero chilies but I have not grown them before because I cannot tolerate the heat of chili peppers. I always grow sweet pepper plants. This habanada plant has not only grown well, it has been producing many peppers about three inches long. Each pepper has folds and dimples, a broad shoulder, and a tapered end. Now in the beginning of August, the plant has about 10 peppers. I ate one raw and it was not spicy at all. It was not sweet either, certainly not as sweet as yellow and red snacking peppers. Intrigued, I had to learn more.

A search on the Internet told me that several years ago, the University of New Mexico discovered a plant from its habanero line that did not register on the Scoville scale. The Scoville scale measures the level of capsaicinoids, the chemicals that cause the burning sensation or the heat. A normal habanero can reach 300,000 Scoville heat units (very high). They sent seeds to Cornell University plant breeder Michael Mazourek who was interested in peppers at the time. Mazourk was inspired to breed a delicious pepper without the heat as part of his doctoral research. The result was the habanada.

I read that the habanada has “floral properties,” that it tastes like a melon or a guava, but to me it is savory, similar to a soft cheese. I picked them at a more orange than red stage but I will let some mature to red and see how they taste again. With the ones I did pick, I chopped them and made an omelet that was delicious. No doubt chefs will be able to see the possibilities of using habanadas in desserts, as a spread, or maybe even a jelly. It can be used whenever a sweet or hot pepper is called for in an entrée and it certainly can be used to color a dish.

The plant was easy to grow. It is about 3 feet tall now. I used a single stake because a single stake has always sufficed with my other peppers but this plant is bushier so I had to keep it propped up with yarn. Next time, I will use a tomato cage. Oh yes, there will be a next time, I am growing this again next year. My habanada plant grows with my other peppers and tomatoes and they all receive ample sun and water but habanadas do not need as much fertilizer as tomatoes.

I highly recommend the habanada, not only as a star performer in the garden but as a tasty pepper!

Three Heat-Tolerant, Pollinator-Attracting, Deer-Resistant Perennials

We are having a hot, dry streak now which really separates the weak from the strong in the garden. Now is a good time to see which plant is tolerating this weather well in other people’s garden so you can copy for your own garden.

On one particularly hot day this past weekend I was downtown visiting the Smithsonian museums. I spent a lot time in the Pollinator Garden, next to the National Museum of Natural History. This is a 400 x 40 feet area on the east side of the museum at 9th Street between Constitution Avenue and the Mall. The Pollinator Garden is managed by Smithsonian Gardens staff and is a wonderful place to relax and watch the butterflies.

I noticed several plants that were tolerating the heat well, that is, they were in full sun and not covered in powdery mildew.  As expected, they were definitely attracting bees and butterflies. These seemed worthy of copying in my garden. When I got home I looked them up and learned that they are rabbit and deer resistant as well as being full sun, drought-tolerant perennials. This is not to say there weren’t other worthy notables in the Pollinator Garden but these are definitely plants to add to my collection next year!

Wild Petunia

Although this plant is called wild petunia (Ruellia numilis), it is not related to petunias. These plants have lavender blue flowers that bloom from summer to fall. They are low growing with a trailing habit, reaching about a foot tall. They can serve as a groundcover and be used as a spiller in a container.

Allium ‘Millenium’

‘Millenium’ is a member of the onion family (Allium) grown for its ornamental, purple globe flowers. The plants grow to 1 to 1 ½ feet tall, providing a strong vertical interest.  They are great in the garden and can be used in containers as thrillers. After the flowers fade and die, the globe structure becomes tan and remains for a while, which also provides interest.

Walker’s Low catmint (Nepeta) is a member of the mint family, so it has gray green aromatic foliage. In the summer, the plant has small, lavender blue flowers, but each stalk has so many that sometimes the plant seems covered in a purple haze. The plants are low growing, about a 1 to 2 feet tall, and used as a groundcover or small shrub.

Walker’s Low Catmint

Hardy Hibiscus: Summer-Flowering, Native Shrubs

Amaretto

This summer I am enjoying two hardy hibiscus plants in my Virginia garden. I planted them last year along the perimeter of the backyard where the water runs through like a river when it rains. It is a full sun, exposed area and the plants are blooming their heads off.

Hardy hibiscus plants (Hibiscus moscheutos) are native to the eastern United States and are common in swampy areas. They typically grow 4-5 feet tall with large hibiscus-like flowers. The flowers only last a day, attracting pollinators, butterflies, and hummingbirds. For years, several cultivars have been available with flowers in the white, pink, and red range.

My bushes come from a new series of eye-popping colors.  I have Amaretto (salmon-colored flowers) and Bleu Brulee (lavender petals with dark red center) from J. Berry Nursery’s Summer Spice Hardy Hibiscus collection. This is a wholesale nursery but their website has a retailer locator. The collection has unusual flower colors – from dark red chocolate to cornflower blue.

Bleu Brulee

My plants were very small when I planted them last summer but they grew quickly. In the fall, after the first frost, I cut the stems down to about 4 inches above the ground. They overwintered well but as with all hardy hibiscus plants, they were late to the dance. Just when I thought the bushes might be dead, I saw new growth at the base in May. The stems grew so fast that by June the bushes were about 3 feet tall (this series also is more compact). Now in July, they are covered in flowers constantly visited by bees. Hardy hibiscus plants are also deer-resistant, although I have seen some Japanese beetle damage on the foliage. I like their large flowers, especially since I can see them from the house. I have a few areas in my garden where there are depressions in the ground that remain damp after the rain or low lying areas through which rain water channels and hardy hibiscus plants are perfect for these areas. In addition, they thrive despite our heat and humidity and provide great color all summer long.