Garden Edition: May 2001
by Linda Coyner
May is the month when waves of colorful bedding plants flood local nurseries and gardeners are presented with a delicious quandary: which to choose?
Amid a rainbow of shades and shapes, buyers ferret out time-tested favorite plants, perhaps experimenting with color or a new variety. Some of us also gamble on something untried to keep things interesting. Besides, today's favorites must have been newcomers at one time. What had I learned from all the plants I'd experimented with over the past few years in my subtropical (Florida) and temperate (New York) gardens was that only a few had escaped the compost pile and were worthy of recommending.
The final four plants I've narrowed my choices down to are long-blooming, colorful and, virtually foolproof. They are also relatively unknown but still readily available at mass merchandisers like Home Depot.
At the top of my list is the petunia-like Calibrachoa, which I first had to learn how to pronounce: kal-ih-bruh-ko'uh. When I saw my first Calibrachoa two years ago at an upscale nursery, I was captivated by the bright earth-tones of the flowers, which enveloped the fine foliage of the plant. This mini-petunia is a low grower that produces a carpet of one-inch trumpet-shaped blooms. The most common label is Million Bells, which was originally released to the market three years ago in trailing and upright forms. The trailing varieties come in purple (which is actually a blue), pink, yellow, and white, usually with a yellow throat. The upright form comes in terra cotta and cherry pink.
Calibrachoa from other breeders may be labeled Colorburst or Liricashowers. According to one industry trade source, the main difference is that Colorburst plants have a more mounding habit than lower-growing Liricashowers, and slightly different colors. This vigorous plant has a graceful draping habit that makes it perfect for cascading over containers and window boxes. It works as a low edge along walkways and as a front-of-the-border plant. The upright form has branches that are a bit more vertical than the trailer--up to nearly a foot--but still arching. In containers, the upright form creates a bushier head above the pot, something I prefer. The trailing types also respond well to cutting back, which generates more growth and blooms.
Despite its delicate appearance, calibrachoa needs full sun. With proper care (see below), you can expect nonstop flowering for up to three months or until frost with no deadheading. In the mild-winter climates in zones 7 to 11, it may thrive all year. The key to success with a calibrachoa is to keep the soil cool and moist with mulch and consistent watering. It also responds well to feeding every couple weeks. In a container, though, you'll need to feed weekly.
Cannas made my list, thanks to the new varieties with fancy leaves. Before I could even appreciate cannas, though, I had to get over a bad attitude. They seemed so stiff and awkward and, well, old fashioned in a bad way. Now I look at them in a different light, so to speak. Their large, bold leaves add a tropical feeling to the garden, making their gladioli like trusses of red, pink, orange and yellow almost unnecessary. Fancy-leaf varieties have spectacular foliage. My favorite is C. 'Tropicanna', which has green leaves that unfurl to show burgundy stripes that turn red, pink, yellow and gold. The flowers are brilliant orange. This variety is a giant canna, averaging about 5 to 6 feet in height.
Another variety with exotic markings on the leaves is C. 'Pretoria,' also called 'Striata,' and 'Bengal Tiger'. The flowers are huge and melon orange on 3- to 4-foot strong tall stems, and while they are very showy, it is the foliage that is truly outstanding. The large leaves have swirling stripes of blue green, light green, yellow, and ivory, all with the narrowest outline of red along the edge. Either variety is dynamite in the border or as the centerpiece in a large container.
My only caveat applies to cannas in general: leaf rollers and slugs love cannas. They can reduce the leaves to tatters. A friend tipped me off to her secret: Di-Syston, a systemic, which she adds to the soil when planting. If slugs are the only problem, Escar-Go!, is the safest way to deal with them (Gardensalive.com). Beyond that, cannas require plenty of moisture and full sun. Keep in mind that they're a tender bulb and need to be dug up and brought in where winters drop below freezing. Hardy in zones 7-11; elsewhere dig and store the rhizomes in a moist frost-free place.
Dragon Wing Begonia
Breeders at Pan American Seed Company crossed an angel-wing begonia with a wax begonia to get an exciting new hybrid called Dragon Wing Begonia. It is ideal for bedding and container gardening, just like its cousin the wax begonia, thriving in both shady and morning sun locations. Leaves are glossy green and shaped like angel wings. The plant is covered with large, heavy clusters of dangling flowers in scarlet or pink, all during the summer and all year, if you live where winters are mild.
The huge panicles of flowers hanging down make this plant ideal for hanging baskets on the front porch or in large containers. I've seen plants in a large container reach 36 inches tall and wide but because of their profuse flowering and self-cleaning habit they're messy on a lanai or patio. I especially like them planted right in the beds where I don't have to worry about the flower drop. Like other angel wing-type begonias, Dragon Wing produces new shoots called canes from the base of the plant. Break back any unsightly or long canes to the base when shaping to give them room to develop.
If you'd like more plants, plant those canes after dusting with rooting hormone powder. Typically Dragon Wing reaches a height of 18 to 24 inches with a spread of 8 to 10 inches. My Dragon Wings reached about 24 inches tall and spread to about 18 inches. They tolerate a wide range of growing conditions, too, including drought. In the South, where I am, Dragon Wings seem to do best in some shade. My latest plan is to put my new plants in the shade around the trunks of some 8-foot majesty palm trees. In the North, they should be grown in full sun with some afternoon shade. According to one grower, too much sun causes the edges of the leaves to turn dark red and curl. They also exhibit some cold hardiness and can take several hits of temperatures in the low 30s with no problem. Mine withstood several brief freezes this past winter just fine.
Since Dragon Wing flowers are self-cleaning, there's no need to pinch off old ones. Even so, I pinch mine a bit since the plants are in a prominent location by the front walk. Dragon Wing isn't fussy about fertilizer, either. I use slow release food about every three months for plants in the ground. Potted plants, obviously, would require more. The breeder recommends an all purpose fertilizer about every two weeks. One expert reports that the leaves turn a reddish bronze hue if they're not getting enough food, something I haven't noticed.
This single-petal daisy caught my eye at a roadside nursery in New York a few years ago because of its striking center, which was a striking azure blue. It seemed, well, extraterrestrial. It's also called "Freeway Daisy" or "African Daisy," and originates from South Africa. The flowers are good-sized, up to 2 inches across. Besides purple, it comes in silky colors such as white, pink, magenta, and cream/yellow/orange tones. My current favorite in the border is white with a blue center. The plants' natural habit of multi-branching makes them bushy mound of glossy dark green foliage. The giant form usually stays 18 inches or under; dwarfs, 12 inches.
Some of the unusual varieties have variegated foliage or spoon-shaped petals reminiscent of some mums. I've been intrigued by the spoons but haven't tried them. Two of the best are supposed to be Nasinga Series from Cape Daisy, available in white, dark pink, purple, and cream, and the pink flowering Sunny Sonja. Silver Sparkler is the only variegated one I've read about. It's supposed to have bright cream edged leaves with a large white flower and blue center. The recent rush of introductions reflect the industry's effort to improve the plant. One was problem was its tendency to stop flowering at high temperatures. Breeders were also trying for more regular flowering and growth habits of some varieties. Both problems seemed to have improved, if not solved. With the new cultivars, flowering may slow during the heat of summer but shouldn't completely stop and growth and flowers are said to be more uniform.
One characteristic gardeners will have to live with for awhile is the flower's habit of closing at dusk. Breeders are still hard at work on that one. Among the recent introductions is Passion Mix, a dwarf that is available as seed. It has flowers in purple, rose, and white. In 1999 it was chosen as an All-American Selection. According to Thompson and Morgan, it's an easy seed to start. Care is very straight-forward. The plants are drought tolerant and require a sunny position for the flowers. If it gets shaded by other plants, flowers may not fully open, something I discovered when a taller plant cast its shadow over the calibrachoa. The flowers must be regularly dead-headed to prolong flowering. In repayment, you will enjoy up to 8 months of flowering. Osteospermums are generally trouble free plants. The only problem I've encountered is aphids, which I treat with soap spray.
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canna bengal tiger leaf http://www.crownsvillenursery.com/images/CannaBengalTigerleaf.jpg
dragon angel wing begonia