Magic by Moonlight

Victoria ‘Longwood Hybrid’ in the center pool of Longwood’s Waterlily Display

The mysterious behavior of Victoria flowers has stirred people’s imagination ever since this giant water lily was introduced into cultivation in the mid-nineteenth century. Native to South America, Victoria evolved into two distinct species: Victoria amazonica inhabiting the backwaters of the Amazon and its tributaries and Victoria cruziana found further south, along Río Paraguay and Río Paraná.

The massive leaves of Victoria cruziana are valued for their high rims

The huge flowers of the Victoria reveal much about the ancient origin of waterlilies as some of the earliest flowering plants on earth. They open at sunset, spreading numerous white petals above water, providing a safe landing platform for nocturnal scarab beetles, which are notoriously clumsy fliers. Beetles are attracted to the flowers by the nutritious starchy appendages on which the insects feast. The appendages are tucked along the walls of a spacious floral chamber hidden below the many whorls of petals. The pollen grains delivered by the beetles fall to the floor of this chamber, where they germinate sending pollen tubes to fertilize ovules embedded in the spiny ovary underneath.

While the flower spreads its petals in the evening its temperature rises up to 20 degrees Fahrenheit above the ambient. This rare phenomenon facilitates the diffusion of the flower’s delightful and seductive fragrance, which guides the incoming beetles into the floral chamber and improves chances for successful pollination by keeping the insects warm and active throughout the night. In the morning, Victoria folds back its petals, closing the entrance to the floral chamber, effectively trapping the beetles inside. When the flower opens again the following evening, the most magical transformation takes place. The petals that were pure white the previous night are now variously suffused pink and purple.

Flower of Victoria ‘Longwood hybrid’ as it begins to close after its first night bloom

The color change is an indication that the flower is entering its male phase of development. The stamens—the male parts of the flower that circle the entrance to the floral chamber and were inactive on the first night—now shed pollen on the beetles scrambling out of the flower. Free at last, the beetles carry a new load of pollen to the next flower that opens that evening, thus assuring cross-pollination. Following the release of the beetles the flower closes for the second time and sinks under water never to be seen again. This mesmerizing ritual is repeated in the backwaters of South American rivers every night and has done so for millions of years.

The history, biology, and allure of the Victoria will be explored in my upcoming book, Victoria: The Seductress, which will be released in March of 2013. Visitors to Longwood can experience the mystery and the majesty of Victoria during a new exhibit produced by Longwood Gardens, opening in 2013. While visiting Longwood this summer, please be sure to spend some time in our Waterlily Garden, which reaches peak bloom in September, and enjoy the seduction of the Victoria for yourself.

UPDATE (May 2, 2013): Victoria: The Seductress is now available for sale online at shop.longwoodgardens.org

Read Full Post »

Desperately Seeking Scents

The past year has been an olfactory adventure in Longwood’s research greenhouses. In preparation for Making Scents: the Art and Passion of Fragrance, we brought in a variety of fragrant plants for trial. Some plants, such as roses, are common and easy to obtain. Fragrant varieties such as Rosa ‘Secret’s out’,  R. ‘Gros Choux d’Hollande, R. ‘De Resht’, R.  x centifolia, R. ‘Compte Chambord’,  and ‘Jaques Cartier’  will be making an appearance in the Conservatory during the exhibition.

Rosa 'Comte-de-Chambourd'

Other fragrant plant requests are more exotic and elusive. Everyone has heard of frankincense and myrrh, but very few people grow them. I know how rare they are, because I was given the task of locating and purchasing these plants. Alas, I did not have the aid of three wise men to guide me, so I was left to my own devices. Fortunately, I had the help of fragrance expert Art Tucker, many horticulture interns, and the Internet. Surprisingly, frankincense can be found at a nursery in New Jersey.  Myrrh came from a nursery in the the Southwestern United States. Both plants exude a sap when the bark is wounded that hardens into a gum.  The gum is used to produce the fragrances of frankincense and myrrh.

Frankincense

One of the most surprising and delightful fragrant plants was already in Longwood’s plant collection. Senna didymobotrya or “Popcorn Senna” emits the pleasant aroma of hot buttered popcorn when the leaves are gently brushed.  I always enjoy watching the faces of people who are not familiar with the plant when they get the first whiff of hot buttered popcorn. This plant should be planted near movie theaters!  Golden yellow flowers grace this plant, which increase its ornamental value.

Senna didymobotrya

Another quirky, fragrant plant has been kicking around Longwood’s greenhouses since 1957. Paramongaia weberbaueri was collected on the slopes of the Andes in Peru. It looks like a giant daffodil, blooms in the fall and has an amazing fragrance. In fact, my first indication that Paramongaia was in bloom was the sweet fragrance that filled the greenhouse. I looked around to see where the scent was coming from and was amazed to see a daffodil-like flower blooming in the fall!

Paramongaia weberbaueri

Aloysia virgata, or sweet almond bush, has been a work horse in our greenhouses. It produces spikes of fragrant white flowers all year long that resemble Buddleja flowers. The sweet, nutty aroma fills the research greenhouses, and sometimes even permeates into the hallways of the headhouse. While visiting the Harry P. Leu Gardens in Orlando, I caught the sweet scent of almonds on the wind nearly 200 feet from the tree-like Aloysia virgata that was growing in one of the beds.

Speaking of Buddleja, there are two pleasantly fragrant varieties slated for display in the Gardens this year. Buddleja asiatica is a species that blooms in January, with white flowers and a pleasant fragrance.  We trialed this plant in our Research Department a few years ago in hopes of finding another winter-blooming Buddleja to supplement the other Buddleja species that we use from Mr. du Pont’s time.  ‘Winter Waterfall’ is a newcomer that will be making its Conservatory debut this year.  It resulted from a cross with Buddleja asiatica. It has a slightly different fragrance than B. asiatica and white pendulous flowers, and it blooms in November and December, which makes it a perfect addition to the Christmas display.

Buddleja 'Winter Waterfall'

The award for the most exotic fragrant flower goes to Passiflora ‘Ruby Glow’.  Not only did this plant have the best fragrance out of all the Passiflora trialed, it also had the best foliage.  The fragrance is tangy and flora. The flower is a site to behold. It resembles some strange sea creature with tentacles.

Passiflora 'Ruby Glow'

I have to say that not all of the plants cooperated. Cestrum nocturnum produces an amazing vanilla fragrance that smells heavenly. Unfortunately, it is only fragrant in the early hours of the morning when the garden is empty, and most folks are sleeping. On cool mornings when the greenhouse vents are locked down, the sweet vanilla scent is trapped in the greenhouse, and I can’t help but smiling when that sweet smell surrounds me.

Some smells are downright unpleasant. Caryopteris divaricata ‘Maxim’ smells like bad onion soup when the leaves are brushed. Plectranthus neochilus is also known as the skunk plant, and you can smell why. The scent of it lingered in the headhouse for an entire day after I transported the plant through the area, causing several people to comment. While pruning a lemon-scented Eucalyptus, I became nauseous. For a few minutes I was convinced that I was coming down with stomach flu, and needed to go home. Thankfully, the feeling passed, and I realized that my discomfort was coming from the smell of the Eucalyptus. Yuck!  I try not to get to close to that plant.

Trialing fragrant plants was extremely interesting.  The first question I got whenever someone new entered the greenhouse was “What is that smell?” Since we were surrounded by so many fragrant plants, it was an adventure to find exactly where the scent was coming from. I hope you also have a great adventure when you come to see these plants in the Conservatory for Making Scents: the Art and Passion of Fragrance, which opens April 10.

Read Full Post »

Passport to the World

I love the theme of the 2010 Philadelphia Flower Show–Passport to the World (through March 7). This year’s show features gardens themed to some of the world’s richest horticultural locations, including South Africa, Brazil and the Netherlands! More than 60 professional organizations have been grooming their best plants and planning the most innovative designs to fill the Convention Center with treasures from around the world for the 8 day show. Here at Longwood Gardens, we’re proud to be a part of the show by featuring some of the most exotic plants that we have collected and cultivated over the years. You’ll see our plants immediately upon entry to the Flower Show, in The Explorer’s Garden, which is sponsored by the Pennsylvania Horticultural Society.

Victoria 'Longwood Hybrid' in summer

A 28′ tall hot-air balloon floats magically overhead while underneath you’ll marvel at Longwood’s incredible water-platters (Victoria ‘Longwood Hybrid’) which have pads that are between 3-4′ across!  We also have some of our most prized South African native plants on display, including the winter red-hot poker (Veltheimia) and Chasmanthe bicolor.  From the Portuguese island of Madeira, Longwood collected parent seed for our hybrid blue cineraria (Pericallis x hybrida).  From the Canary Islands off the coast of northwest Africa comes Echium wildpretii with its dramatic towering spires of pink.  From the same family of islands hails sweet broom (Cytissus x spachianus) with its elegant arching stems of electric yellow. Lastly, be on the lookout for the elusive Himalayan blue poppy (Meconopsis) as they might decide to flower this week as well!

Longwood Gardens, with our 4-acre conservatory complex is only 30 miles from the Philadelphia Flower Show and offers a world of garden adventure each day of the year!  I invite you to come and explore our gardens that feature designs from around the globe.  Let’s look at a few inspirational plants and spaces that are in full bloom right now.

Burle-Marx's Cascade Garden

The Cascade Garden was designed by Roberto Burle Marx from Brazil.  It has been growing and evolving for almost 20 years!  In the center of the garden emerges what looks to be two giant tree trunks from the rainforest, which have been covered with vines and epiphytic plants.  As you follow the curving path through the garden, you are greeted with colorful bromeliads and philodendrons, many of which are native to Burle Marx’s home country.  Look up to the walls and see that they, too, are draped with exotic foliage in many textures and colors.  The sound of water fills the air as brimful waterfalls cascade to clear pools below.

Mimulus 'Valentine' in the Mediterranean Garden

Nearby,  the Mediterranean Garden showcases many plants that are native to South Africa, including Aloe capitata, Euryops pectinatus, Chasmanthe var. duckitii and Clivia miniata, which blossom each winter with heads of bright yellow flowers.  Filled with sweet nectar,  the pink form of winter red-hot poker (Veltheimia) forms a soothing sweep underneath graceful pepper trees (Schinus) as vibrant purple Cyclamen and golden Tulip batalinii (both natives of Persia) mix sweetly near the pathway.  The Mediterranean garden was designed by a Californian garden designer and features the beautiful California native flower Mimulus ‘Valentine’ that flanks the central bench.

Hippeastrum 'Lemon Lime' in the Mediterranean Garden

Longwood’s relationship with the foremost bulb growers in The Netherlands brings us some of the best cultivars of lilies, tulips, narcissus and amaryllis available.  You’ll find one of the newest plants in the Orangery–Lillium ‘ Florian’.  The sweetly fragrant blossoms are the most delicate pink infused with white.  The stately petals stretch almost 10″ across and the strong stems reach almost 3′ in height!  Narcissus ‘Constantinople’ is a tazetta-type narcissus that is commonly known as the paperwhite.  This cultivar boasts strongly ruffled petals and an intoxicatingly sweet scent that is hard to describe!  This type of narcissus is not reliably hardy in zone 6, but gardeners in warmer zones 7 and 8 would be wise to try this cultivar in your garden.  Equally suited to warmer zones is Hippeastrum ‘Lemon Lime’.  This has to be my favorite bulb in the Conservatory now! The elegant floral display atop each lengthy stem is a sophisticated shade of chartreuse.  It complements warmer colors nicely and will have a blush of pink in very cool weather. Look for it in the Mediterranean Garden meadow this week.

Longwood Gardens has combed the world for some of the most exciting plants to share with you on a daily basis.  I invite you to join us and travel the globe as you stroll through our Conservatory!

Read Full Post »

Longwood Water-Platter Ready for Flower Show Debut

This year the Philadelphia International Flower Show produced by The Pennsylvania Horticultural Society (PHS), America’s first horticultural institution, will showcase plants from around the world in the 2010 show “Passport to the World.” A special exhibit called the “Explorer’s Garden” will greet guests, and will capture the spirit and adventure of early plant exploration. For the “Explorer’s Garden,” Longwood is forcing its signature Victoria ‘Longwood Hybrid’ water-platters. Longwood developed Victoria ‘Longwood Hybrid’ in 1961 by crossing Victoria cruziana and Victoria amazonica from seeds collected from plant exploration trips to South America. Over the years Longwood has embarked on more than 50 exploration trips to every continent except Antarctica.

This is the first time that Longwood Gardens will be growing plants for the Flower Show, and the Victoria platters are a favorite of Longwood’s guests! We are excited to share this amazing plant with the Flower Show’s 250,000 visitors. If you have visited Longwood during the summer months, you know that these plants are one of the biggest attractions in our water garden display.

'Longwood Hybrid' Water-platter

Once the excitement of being invited to participate in this year’s flower show subsided, the real fun began. We sowed the seeds for the plants in late November to give us as much growing time as possible before the opening of the show at the end of February.

Victoria seed

Within two weeks the seed germinated and the race was on! When we began, we were hoping to have 3-foot wide leaves for the show. We added lights to supplement the short days of winter, and heated the water to 80 degrees Fahrenheit using submersible aquarium heaters combined with small pumps to help circulate the water. Unsure exactly how the seedling would respond, we started with 18-20 hours of supplemental light. Within 10 days the tiny seedlings had grown to nearly 12 inches in diameter.

We quickly realized that is was not only possible to have 3-foot leaves for the show, but is was likely that these impressive plants would reach 4-feet+ in diameter. We had to make plans for a temporary tank to be built in our Production Greenhouse. What a luxury to have a staff of craftsman on the property that could help us along the way! Once the tank was built we added a liner, supplemental lights and heat. The new tank measured 10 feet x 10 feet, giving us room to grow two plants.

"Sedan" carrier used to transport Victoria

Since the leaves were growing so quickly, we turned our attention to the next challenge at hand: how to move plants with 4-foot leaves into their new tank. We had to stabilize the leaves so that the thorns on the underside did not damage themselves or other leaves. Once again our carpenters came to rescue. After several discussions we decided on a structure what could best be described as “sedan chair,” similar to a chair that would be used to carry nobility. How fitting since the plant is named in honor of Queen Victoria! The leaves were sandwiched in a bed of wet sphagnum to help keep the plant hydrated, and finally wrapped in a layer of plastic before being sealed for the move.

Sandwiching Victoria leaves between layers of sphagnum moss

Once the plants reached their new location, we removed the sphagnum from the leaves and lifted the pot from its “bed.” Each leaf was supported by a gardener, who carefully watched that the thorns and petioles didn’t inflict injury. Now in their new home, the Victoria Water-platters are growing happily and waiting for their chance at stardom at this year’s Philly Flower show.

Carefully moving Victoria to tank in Production Greenhouse facility

Guests to the “Explorer’s Garden” will also see New Guinea impatiens, now a staple in home gardens around the country, but first brought back to the US after a Longwood-sponsored trip to New Guinea in 1970. Other notable plants include the Meconopsis or blue-poppy.  This startling blue beauty requires the cool climate of the Himalayas, Scotland or Alaska to flower, but Longwood growers have successfully forced Meconopsis for display in the Conservatory each March since 2002. Longwood is also contributing Echium candicans ‘Select Blue’, a perennial with a bright blue spike and Echium wildpretii that can produce flower spikes up to five feet tall.  Finally, Longwood is also growing a selection of large specimen poinsettias, paying homage to the popular holiday flower that was on display at the very first Philadelphia Flower Show.

See you at the show!

Read Full Post »