Growing Tall
With greenhouses about to gear up for spring again, the appearance of the center spike mixed container is inevitable. Dracaena spikes are a cheap, easy height components, and there does seem to be a market for this product. Personally, though, I can’t stand it. (Apologies in advance for anyone who breeds or grows dracaenas; it’s nothing personal.) In fact, if my headstone could say, “she eliminated the spike,” I would rest peacefully.
So when I was at Pack Trials this year, I started taking note of some of the plants being introduced that would make great height components. To my surprise, there were tons of options everything from tropicals to trees and foliage to flowering. There were so many options, in fact, that I couldn’t cover everything in one article. Instead, I’ve chosen a few of my favorites and highlighted some others in the figure on page 63. These are by no means all of the options, but it will get us to start thinking about what else can go in a mixed container, and it’s a great first step in my crusade.
A Few Favorites
Before a brief description of the plants, a little explanation might be in order. When I selected the following, I was thinking about large mixed containers, at least 12-14 inches. This would also necessarily dictate large plants. You’ll notice that the minimum height is 24 inches. There are many great plants that fall into the 18- to 24-inch range, and if you’re doing smaller containers, these might work great.
The last consideration is pricing. If you are creating a large mixed container and growing the height component to 3-4 feet, that container has been in the greenhouse a long time; it was expensive to produce, and it should be priced accordingly. Besides, you’re taking a lot of effort to develop something creative, something out of the proverbial box; reap the benefits.
With that said, the following are five recent introductions to use as height components.
Phormium. Look out mixed containers, height components will never be the same again phormium has hit with a vengeance. This crop started showing up a few years ago in high-end mixed containers, but with limited availability, in part because it’s difficult to root, making the prices too high for mass production. We’re hoping that the new and improved Lancer series from Bodger Botanicals will change all that. With three new and two improved colors, this series now has a variety to fit any color combination and enough breadth to accommodate the demand. Mature plants will reach approximately 3 feet tall so are best produced in 6-inch or larger containers, preferably 1-gal. These are Australian natives, so they’re very tough over-caring for these plants is about the only miss-step you can make. Use coarse soil, allow to dry completely in between waterings and feed only every 6-8 weeks for beautiful plants that really impress.
Digitalis. Goldsmith Seeds brings you the first F1 hybrid digitalis on the market the Camelot series. Its high germination and uniform growth and flowering are a few of the highlights of this series, but Á its secondary spikes that provide numerous high-quality and strong stems are the real focal point.
An early summer variety, radicle emergence on Camelot occurs in 3-4 days, plug production takes 4-6 weeks and 1-gal. crop time is 16-20 weeks from transplant, though it can be produced in as small of a container as 6-inch. Vernalization at 45° F will be needed for two weeks.
Camelot is a reliable first-year flowerer and heavy second-year bloomer, with flowers that last two or more weeks. Available in four colors Cream, Lavender, Rose and White the huge tubular florets are highlighted with speckled throats. Camelot grows 31?2-4 feet high and 24-30 inches wide
Something to look for: In trials, plants grown in greenhouses with additional lights exhibited stretched habits and loose flower spikes. Crops grown cool in protected cold frames will produce compact plants with good lateral development of secondary spikes. If needed, Camelot will respond to B-Nine at 2,500-3,500 ppm or Sumagic at 3 ppm at stage 3. You can find more production advice from Paul Pilon on page 70.
Hibiscus. Never thought of yourself as a woody grower? Well, maybe the marketing agreement between Spring Meadow Nursery and Proven Winners has opened your mind to the possibility of using woodies. The crop time can be a little long on some varieties, but others will fit right into perennial schedules.
The hardy hibiscus Chiffon series is certainly worth looking into. The 5- to 8-foot plants are covered with either lavender or white flowers all summer, and they can be trained into attractive patio trees. Large single flowers have a lacy center that gives an anemone-like bloom. An award-winning variety, Chiffon was bred to perform in cooler climates.
Canna. I don’t often go crazy about a tropical foliage plant, plus I hate cannas, but canna Tropicanna from Anthony Tesselaar is not your every day canna. Tall and exotic in profile, Tropicanna unfurls each new leaf with a show of burgundy stripes fanning out from a chartreuse center vein, and quickly the display includes an array of red, pink, yellow, gold and deep green.
Despite its dramatic, multi-hued appearance, Tropicanna retains a canna’s ease of cultivation. There are few requirements for a really spectacular plant. Being a tropical, it needs high light and warm temperatures. In fact, for a full color presentation, maintain temperatures above 58º F.
Nicotiana. ‘Tinkerbell’ from Floranova is a great new addition to the nicotiana family. It is a very vigorous, large hybrid, which is not common in other nicotiana varieties. Flowers are rose with green reverse and blue pollen, making this a very unique high-end color. In order to get darker colors, Tinkerbell needs cooler temperatures. It has a widely branched habit and is very self-supporting. While Tinkerbell can be produced in 4-inch pots, it is best in larger containers for mass plantings. Tinkerbell received a Fleuroselect Quality Mark in 2003.
Tinkerbell flowers through the summer and has good disease and weather tolerance. Approximately 1-inch flowers are supported on 36-inch stems. This plant should be sown from winter to early spring under glass at 64-75° F. Plants should be hardened off and planted out after the danger of frost has passed.
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