Plant Preview

Welcome to Plant Preview, a blog dedicated to helping gardeners learn about gardening techniques and preview new plant cultivars. Read about new plants here first and hear how your "comrades in compost" are making use of new plant introductions in their gardens and landscapes. Blog author Geri Laufer is a life-long dirt gardener, degreed horticulturist, author and former County Extension Agent. Plant Preview is copyrighted by Geri Laufer.

Friday, August 27, 2010

Sweet Potato Vine; I discovered it flowers!

I’ve had a long love affair with sweet potatoes. As a child, I stuck a regular sweet potato with toothpicks and submerged it halfway in water in a clean pickle jar, then set it on my windowsill and enjoyed watching the green vines grow to frame the window during a long Ohio winter. Later, restaurants served delectable sweet potato chips, and after that our children’s Montessori teacher served raw sweet potatoes as an in-school snack.

About 10 or 12 years ago I came late to visit the UGA Summer Flower Trials in Athens, Georgia. I found everyone gone, but there was still a truck piled with free samples, including a brand new but totally wilted yellow ornamental sweet potato vine. Never dreaming that such wilted cuttings would survive, nevertheless I took a couple and stuck the cut ends in my water bottle for the drive back to Atlanta. By the time I was home, the vines were perky and the leaves all stood erect. They went on to root and grow into a wide mat in the garden that year.

Marguerite sweet potato vine is the chartreuse variety that turns almost yellow in full sun, and takes the hottest sun and abuse, dry, south-facing window boxes, hell strips, or containers set on hot concrete paving, and yet grows luxuriantly. Though wilted in the hot afternoon sun the 6 foot container (left) will be refreshed in the morning, or sooner if it gets some water. 

Marguerite’s original partner, Blacky, (right) had dark, purple-black leaves and has been joined by a new cut-leaf black version called Midnight Lace that was sent to Garden Writers and widely marketed in 2009.

Then this year, imagine my surprise to find some Ipomoea morning glory-type flowers on my Blacky vines! Though small and pale pink, they are the same, familiar, trumpet-style, Convolvulus family flowers. 

Have I been unobservant? I never noticed any flowers before this. What about you? 

Monday, August 23, 2010

Tansy, a Controversial Herb

On my trip to the Rockies I was attracted to a beautiful yellow flower growing alongside a dumpster, and recognized Tansy from herb gardens in Atlanta. My Colorado friend cautioned me that, yes, although it was Tansy, it is considered an invasive exotic weed and not welcomed in the West.

Common Tansy, Tanacetum vulgare is a European herb documented in medieval herbals as a medicinal and culinary plant used as a cure for intestinal worms, aid to rheumatism, digestive problems, fevers, used to heal sores. Meat was frequently rubbed with common Tansy to repel insects and prevent decay. More recently, common Tansy has been cultivated for its insect repellent, disinfectant and preservative effects.

Known for its flat-topped clusters of bright yellow buttons, the disk flowers of Tansy have no ray florets so it looks like the center of a common daisy. Thriving in full sun and well-drained soil, the leaves of common Tansy (or the even more beautiful leaves of fern-leaf tansy) are lovely and can take the place of a fern in a sunny garden.

About 20 years ago I got a recommendation to plant Tansy to repel ants, so I did plant it in an Atlanta herb garden, and confusingly had a large anthill grow up around it. Furthermore, Tansy is toxic in large quantities and is not used medicinally nor for culinary purposes today.

Like Purple Loosestrife, in northern and western regions of the US, common Tansy has escaped from gardens and is considered an invasive exotic weed, even listed as 'noxious' in some states because its many tufted seeds are dispersed by wind and water, while new plants form from even the smallest root fragments, making it hard to eliminate.

I guess it just goes to show that one man's ceiling is another man's floor.


Friday, August 20, 2010

Top 7 Benefits of Garden-Related Travel

This week I'm writing live from an anniversary trip to Colorado, and I've been struck by the many impressions of travel. 

New plant hardiness zones  Upon arrival, Colorado’s huge population of blue spruce jumped out as the most outstanding plant feature of the landscape. Sweet peas and columbine are still blooming in the gardens; long since past in Atlanta.

New ecosystems  High plains grassland vegetation is so different from the familiar mixed conifer forest of my home in Atlanta. The Denver Botanic Garden has devoted a section to the native grassland, in bloom in mid August, mixed with bright daisies and coneflowers. Was that tumbleweed rolling amidst the solar farm at the Denver International Airport?

New permutations of old weeds It struck me that both the Shepherd’s Purse and Ragweed were small and stubby compared to luxuriant examples of these weeds at home, and there were slightly different species of bitterweed and yellow composites from the familiar ones in the SE US.

Breathtaking New Sights Off to the west the mountains appear extraordinary. A trip to Red Rocks and Dinosaur Ridge outside Denver produced a totally unfamiliar natural scenery. Traveling expands the mind and creates new memories.

Different culture Check out the intriguing native motif of tile mosaic on the floor of the Denver International Airport, the paintings and prints of wild mustangs hanging throughout and continued influence of the wild west filtered through several generations. 

Activity So much to do, so little time. The demands of a 20 hour day, from an early rising at 3:45 am Atlanta time to dinner with friends ending around 10 pm Denver time, is more than I typically put in at home. Traveling really gets the blood flowing.

Stress relief benefits of traveling The luxury of a departure from the ordinary; of renewing friendships with old friends; of sleeping in; of seeing things you have only read about; are all quite a thrill. 

Monday, August 16, 2010

Vining Hummingbird Magnet for the Garden and Landscape

Garden  Debut® offers a Trumpetcreeper that is a hybrid between the rampant-growing, native Campsis radicans and the showy-flowered Chinese Campsis grandiflora. Madame Rosy® exhibits the best features of both. (Campsis x 'HOMR' PP18394 Madame Rosy®) is a beautiful hybrid that begins blooming in late May and continues through September. Flowers are rosy colored and exhibit a somewhat flattened trumpet shape, 2"-3" across, much larger than the native version. The trumpet-shaped flowers are big and beautiful and attract hordes of hummingbirds from miles around, since it produces quantities of nectar-rich blossoms all summer long. 

The vine grows best in full sun, but light shade and cool temperatures enhance the rosy color. These abundant flowers are produced in terminal racemes 12"-24" long on new growth all summer, and continuous flowering is guaranteed because the vine produces no seedpods. This well-mannered trumpet vine is adaptable to a wide range of soil and climatic conditions. Madame Rosy® is hardy in USDA Zones 6-9.

Because the aerial roots use a powerful adhesive substance to cement themselves to supports, Trumpetcreeper is not recommended for planting near structures but makes a great addition to fences, trellises or arbors. These attractive flowering vines are strong, reaching 10'-15' in 4 to 5 years.

Sunday, August 15, 2010

Trusty Garden Knife Divides Plants

Well-used serrated knife 
Today I am writing in tribute to the indispensible knife I use in my garden. It started life as a serrated bread knife originally purchased 20+ years ago at a discount store for $3.65, and it has served me well for all these years.

Division is economical and quickly yields a modest increase of plants for the garden. One caveat: hundreds of beautiful plants can be legally propagated, but when propagating by division, be careful to respect the plant patent rights and trademark rights of others.  If a plant is patented or trademarked it cannot legally be asexually propagated. Check the nursery label. 

large clump of daylilies
The primary use for my garden knife is the form of plant propagation known as division. Division is the dividing or breaking up of a large plant clump into multiple smaller segments, each with a shoot and some roots. These segments (known as divisions) are then replanted and each one grows into a new plant identical to the original one.

The photos illustrate plant propagation by division using an old clump of tall, maroon daylilies I'm planning to share with a friend. 

Determine where to cut
For example, if I need more Hosta for a new location, I choose an overlarge clump, carefully dig the plant, loosening the roots and lifting the plant from the soil.  I shake off extra soil so I can see the separate shoots, but I do not advise washing off the soil in water, as that turns into a muddy mess. (The hardest plant I ever divided was yellow flag Iris pseudacoris growing in the water at the edge of a pond; it was huge, heavily rooted, wet and muddy.)

slicing through the crown & roots
While some Hostas separate readily into divisions and can be teased or broken apart with my hands, others have a solid crown. With these I use my trusty garden knife to saw through the crown of the plant, creating three or four smaller sections to plant in the new spot.

Crown (white spot in soil) cut in half
Another reason to lift and divide perennials is if they become overgrown, lose vigor or produce fewer flowers. Vigorous growth typically occurs on the outer edge of the clump which has grown into new soil, while the center of the plant languishes. If I notice my daylilies are performing less well because they have gotten too crowded, I carefully fork them out of the ground, remove the soil and separate them into new divisions imagining myself to be a master surgeon. 

Trim away half of leaf surface
None of those old directions: “split apart the main clumps with a hatched, or with two spades inserted in opposite directions” for me. I -refer to investigate where the shoots arise from the crown and consider the optimum placement for each cut. Old growth from the center of the clump is generally discarded. Leaves are trimmed off to reduce water lost to transpiration.

4 vigorous divisions from original clump
Sometimes outside segments of a plant like summer garden Phlox paniculata can be removed and replanted without disturbing the rest of the plant. 

Potted up for future planting
A good rule of thumb is to divide fall-flowering perennials in spring and spring- and summer-flowering perennials in fall, after bloom. And ornamental grasses are best divided in spring because they prefer a long hot period to re-group.

Success! Now I have four strong plants in a large nursery pot to share with a friend who just bought her first house. 

Monday, August 9, 2010

What’s on with the American Community Gardening Association?

In addition to woody ornamentals and flower gardening, I’ve been interested in garden vegetables (and eating them!) since I can remember—planting lettuce seeds and seeing the tiny chartreuse cotyledons against dark brown Ohio soils at ~age 4 ½. I grew up with gardening, but many haven't. This weekend the American Community Gardening Association (ACGA) held its 31st annual conference in ATL, so I applied for a scholarship, was granted a partial one, and off I went. The conference was filled with folks dedicated to being a force for good. What’s not to like?

The program was densely packed with tours of community gardens across Atlanta and with a great variety of educational sessions. Programs ranged from childhood obesity, rainfall retention, biointensive gardening, school programs to raising chickens and goats in community gardens, and from healing gardens to how to preserve the harvest by canning. Several classes addressed the problem of losing garden land, while fundraising and grant writing were not neglected.         
First Lady Michelle Obama addressed the group via video message as did the Secretary of Agriculture, Ferry-Morse attended and gave away wheelbarrows of free seeds to community gardeners representing 37 states and 6 countries. There were plenty of both networking and fresh vegetables on the menu. All in all it was a great conference. Thanks to ACGA for my scholarship and thanks to the local planning committee for their hard work.
Author's photos of Sugar Creek & Oakhurst Community Gardens.