Production Tips For Top Performers: Campanula Persicifolia

Production Tips For Top Performers: Campanula Persicifolia

There are about 300 species in the genus campanula, most native to northern temperate regions. Many are valuable ornamentals and have become classic elements in the garden, adding a touch of grace and refinement. Species range from tiny alpines to 5-foot-tall specimens for the back of the border. The flowers are generally bell-shaped and lavender-blue, white or pink.

Campanula persicifolia is commonly called peach-leaved bellflower because the long narrow leaves resemble those of the peach tree. It is native to Western Asia and Europe, and forms upright spires about 3 feet tall, with many flowers of lavender-blue or white. The plants prefer cool conditions and perform best in Zones 3 to 6. C. persicifolia plants spread and will also self-sow quite freely in the right environment–full sun or part shade, and moist well-drained soil. They are an elegant and showy addition to any border, and also make excellent cut flowers.

We have worked with C. persicifolia previously and confirmed that they do require a cold treatment, or vernalization, for flowering. ‘Takion Blue’ and ‘Takion White’ are new cultivars selected for dwarf habit and good branching (Figures 1 and 2). Reportedly, they have a short vernalization requirement of four weeks at 32 to 35°F.

Materials and Methods

We received 128-cell seedlings of ‘Takion Blue’ and ‘Takion White’ with seven to 10 leaves per plant. Plugs were transplanted and forced at 68°F under one of three photoperiod conditions: nine-hour short days, 16-hour long days created with incandescent lamps or a higher light treatment of 16-hour long days created with high-pressure sodium (HPS) lamps. In the higher light treatment, plants received about 30 percent more total light per day than in the other two treatments. We also cooled plugs for four, eight or 15 weeks in a cooler at 41°F, lighted for nine hours per day.

Results

‘Takion Blue’ and ‘Takion White’ did require cold to flower (Figure 4, page 76). Under our conditions, four and even eight weeks of cold did not result in 100 percent flowering. All plugs that had been cooled for 15 weeks flowered (Figure 5, page 76).

Both of these cultivars were day neutral, meaning that photoperiod had little effect on flowering. Plants flowered after five to six weeks at 68°F under short days or long days.

Supplemental light resulted in more sturdy stems, more lateral shoots and more inflorescences. Both cultivars had more flower buds on the main inflorescence under HPS lights, but all were quite beautiful, with between 25 and 30 flower buds on the main inflorescence.

Heights of our ‘Takion Blue’ and ‘Takion White’ plants when their first flowers opened were 15 to 17 inches under HPS ights and 18 to 22 inches under incandescent lights. Plants were only 12 to 14 inches tall when forced under nine-hour short days. ‘Takion Blue’ was 2 to 5 inches taller than ‘Takion White’ on average.

We have not tested growth retardants on C. persicifolia but paclobutrazol (Bonzi), daminozide (B-Nine) and uniconazole (Sumagic) have been effective on other species of campanula.

Production Notes

We expected shorter durations of cold to be effective, but our plugs required 15 weeks of cold to obtain 100 percent flowering. This response is probably due to the small size of the seedlings we cooled. In many species, particularly seed-propagated, plants have a juvenility requirement–meaning individual plants are unable to flower until they’ve attained a certain size or age. A requirement for cold can interact with this juvenility requirement: Immature or juvenile plants are less sensitive to the cold treatment, thus a longer cold treatment is needed. 

In other trials, colleagues have found that 14-week old 2 x 2 ¼-inch liners of both Takion cultivars have all flowered after eight to 10 weeks of cooling at 38 to 41°F. Also, we cooled our plugs at a slightly higher 41°F instead of the 32 to 35°F suggested, which could have affected their response.

For success with ‘Takion Blue’ and ‘Takion White,’ start with larger plant material or give small plugs time to grow before cold, and provide an ample cold treatment. These varieties should be ideal for spring forcing, and are show-stoppers in the garden center.

Leave a Reply

More From Plant Culture...

May 22, 2015

Nexus Greenhouses Is Optimistic For Expansion Into New Markets

Cheryl Longtin and Mike Porter, who own Nexus Corporation, say they were excited to attend the grand opening of Gotham Greens’ new structure atop the new Whole Foods grocery store in the Gowanus neighborhood in Brooklyn, N.Y., when it opened in December 2013. The project is just one example of some of the new and expanding markets that Nexus Corporation has expanded into over the past few years. Jeff Warschauer, vice president of sales for Nexus, says the company has enjoyed getting to know and working with the founders of Gotham Greens, Viraj Puri and Eric Haley, and Jennifer Nelkin Frymark, the chief agriculture officer, on their innovative approach to business. “They are very excited and work hard internally – just great people,” he says. “From our perspective, it’s great to see that excitement and vision. The employees there are happy and there’s no turnover; they’re only adding new people […]

Read More
Farwest2015

May 20, 2015

2015 Farwest Show Announces Second Annual Equipment Innovation Day

The second annual Equipment Innovation Day will be Tuesday, Aug. 25, prior to the 2015 Farwest show, which will be August 27-29 in Portland, Ore. Equipment Innovation Day, which was enthusiastically received in 2014, offers a real-time opportunity to see new heavy and automated nursery equipment in action. The demonstrations take place in manufacturing and nursery settings, adding value to the showcase. Attendees will be able to talk with participating manufacturers and learn first-hand from innovative growers who use the equipment in daily operations. The day-long event will be held at the main manufacturing plant of GK Machines, Inc., Donald, Ore. Further demonstrations of field equipment will take place at the nearby nursery of A&R Spada Farms, LLC. Bus travel to and from the event is planned, starting at and returning to the Oregon Convention Center. Attendees are welcome to provide their own travel to and from the site. Preregistration is required. The cost […]

Read More
Bee On Flower

May 20, 2015

White House Task Force Releases Pollinator Health Strategy

An interagency Pollinator Health Task Force commissioned by President Obama released its “Strategy to Promote the Health of Honey Bees and Other Pollinators” on May 19. The strategy, released in accordance with the Presidential Memorandum issued last June, is accompanied by a Pollinator Research Action Plan, which outlines needs and priority actions to better understand pollinator losses and improve pollinator health. The recommended actions will be supported by a coordination of existing federal research efforts and accompanied by a request to Congress for additional resources to respond to losses in pollinator populations. Pages 47 through 52 specifically address pesticides and pollinators. The report calls out plant production, native plants, mosquito control and all urban uses in its Pollinator Action Plan. RISE (Responsible Industry for a Sound Environment) says it supports the goals of improving pollinator health and habitat contained in the White House Pollinator Task Force’s release of its National […]

Read More
Latest Stories
Bee on a Sedum

March 17, 2015

4 Key Pollinator Research Projects To Be Funded By Hort…

The Horticultural Research Institute will grant $125,000 in financial support for four key projects as part of the Horticultural Industry Bee & Pollinator Stewardship Initiative. The Initiative has three primary goals. First, to convene a task force to develop a bee and pollinator stewardship program, including creation of best management practices for plant production. Second, to identify and fund research that will help answer key science questions and fill gaps needed to design and refine the stewardship program. Third, to seek to positively position the horticultural community and its customers by collaborating with other compatible groups interested in augmenting pollinator habitat and protection.

Read More

March 11, 2015

Pollinator Initiative Promotes Bee-Friendly Talking Poi…

AmericanHort and the Society of American Florists are working tirelessly with the ornamental industry's Pollinator Stewardship Initiative on a number of new projects.

Read More

February 11, 2015

Infusion Technology Boosts Seed Performance, Study Sugg…

Seven-year-old wheat seed germination can increase by as much as 83 percent, according to a Vital Force Technology Study that looks at the effects of energy infusion technology on plant vitality.

Read More

February 3, 2015

American Floral Endowment Accepting Research Pre-Propos…

If you are pursuing a floriculture research project, now is the time to apply for funding through the American Floral Endowment. Research pre-proposal applications for 2015-2016 funding are due to AFE by June 1, 2015.

Read More

January 27, 2015

Marijuana’s Trajectory And Ascent To Horticultural Cr…

Marijuana growing is poised for change as growers and researchers focus on improving production practices.

Read More

December 9, 2014

Greenhouse Production: Two Years Of Basics & Beyond…

Greenhouse Grower's Basics & Beyond articles cover some of the latest news and research going on in greenhouse production. Here are article links for the last two years.

Read More
GrowIt! App Wins Gold At Design100 2014 US Mobile & App Design Awards

November 24, 2014

GrowIt! App Wins Gold At Design100 2014 US Mobile &…

The social garden app GrowIt! takes the Gold Winner award at the design100 2014 Mobile & App Design Awards.

Read More

November 10, 2014

The Perennial Farm Joins HGTV HOME Plant Collection

The Perennial Farm joins the HGTV HOME Plant Collection growers' network for 2015.

Read More
AmericanHort

November 4, 2014

AmericanHort Publishes Revised American Standard For Nu…

AmericanHort announces the revised American Standard for Nursery Stock (ANSI Z60.1) is now available for industry use. The Standard reflects the consensus of the industry regarding how nursery stock — living plants other than annuals — should be specified and sold within the trade.

Read More

September 26, 2014

Master The Art Of Watering

Watering is elemental to healthy plants, but one of the hardest concepts for new employees to master in the greenhouse. Recommend these tips to start them off right.

Read More

September 16, 2014

Ball FloraPlant’s Las Limas Facility Provides Gro…

Ball FloraPlant’s Las Limas farm in Esteli, Nicaragua, is one year away from full production, but sales and quality from the two-year-old facility are right on track.

Read More
Erysimum 'Cheers' from Darwin Perennials

September 15, 2014

Darwin Perennials Takes Production Offshore In Bogota, …

With its recent purchase of a farm in Colombia, Darwin Perennials is ready to amp up supply of its perennial genetics, to provide growers with tried-and-true varieties and comprehensive production specifications.

Read More

July 23, 2014

Plan Now To Prevent Bract Edge Burn On Poinsettias

Reduce fertilizer and water, and allow your poinsettias to develop slowly during the final four weeks of production to avoid bract edge burn.

Read More

July 11, 2014

Growing Your Crops Above Their Base Temperature

Lowering temperature set points in the greenhouse may help you combat rising heating costs.

Read More

May 1, 2014

Growers Report Nutritional Problems On Geraniums

In recent weeks, several growers have contacted Michigan State University Specialists about leaf discoloration on geraniums, especially the purpling of lower leaves.

Read More

April 22, 2014

How Two Postharvest Care Products Worked On Potted Plan…

What your potted plants look like at retail translates to sales or fails. North Carolina State University researchers report on how two postharvest care products performed.

Read More
Dianthus 'Passion' from Emerald Coast Growers

March 27, 2014

Growing Dianthus Successfully

Here's some advice on transplanting and producing this classic perennial favorite.

Read More
Aquilegia canadensis

March 10, 2014

Tips For Producing Aquilegia

Advice on planting, temperature, vernalization, lighting and more on columbine from Emerald Coast Growers' head grower Josiah Raymer.

Read More