The Celebration series bred by Westflowers is a new generation of calibrachoa. A range of fashionable colors and continual flowering from spring to late autumn make them perfect for brightening any home. Patio pots, garden beds, baskets and window boxes will all display this cultivar in its finest form.
In addition to its attributes for the gardener, this series is bred by one of Europe’s most respected annual producers and is grower friendly. Plants are very uniform in growth habit and flower size. Selective breeding results in the flowers’ ability to stay open for longer periods of time under low temperatures and lower light levels. The semi-upright, semitrailing habit make them a universal choice for both pot and basket applications. Finished plants have a nice round form, which holds up extremely well during shipping.
Their dense habits are petal-packed with vivid colors across the plants for maximum sell-through at the retail level. The series includes 15 striking colors and three mixes. Leading the list of new varieties this year are Snowball, Neon Sun and Neon Rose. The most popular mix, Carnival, is closely followed by Oriental and Spring Mix, each with designer color palettes that appeal to the consumer.
Cuttings should be propagated from November through March for early- to late-spring sales. If they cannot be stuck immediately upon arrival, they may be stored up to 24 hours at 45-50° F.
Choose a well-drained rooting medium with a pH of 5.3-5.5 and the addition of iron chelates. The propagation should be done at 68° F under fog initially before misting with a soil temperature of 68-72° F until roots are visible.
As soon as roots are visible, keep plants misted so the media is consistently moist but not oversaturated, as this will lead to chlorosis of the rooted liners. Begin fertilization with 75- to 100-ppm nitrogen in the first week that roots are visible; increase to 150- to 200-ppm nitrogen as the roots continue to develop.
As the liners grow, appropriate water stress, cool temperatures and bright light will eliminate the need for plant growth regulators. Liners can be pinched three weeks after sticking to promote heavier branching early on. The rooted liners will be ready for transplant four to five weeks after sticking.
High light and cool temperatures will finish plants with ultimate quality. Under ideal conditions, plant growth regulators will not be needed. Maintain a consistent soil pH of 5.2-5.8 for optimum plant growth.
Use a media that allows aeration in the root zone; you can avoid fertility issues by using a loose peat media for the finished container.
Maintain temperatures at 70-75° F days and 55-60° F nights.
High light levels from 5,000 to 8,000 foot-candles are necessary for optimum plant habit, and long days greater than 13 hours will provide the heaviest flowering for the finished crop. For this reason, autumn crops should be started early enough to initiate a heavy flowering before the natural day length shortens significantly. If natural long days are not achievable, night-interruption lighting may be used.
Plants should be fed with a constant liquid feed of 250- to 300-ppm nitrogen, alternating between a 15-0-15 and 20-10-20. If chlorosis becomes an issue, add iron chelates. Plants can occasionally be flushed with clear water to reduce the buildup of salts in the media.
Pinch plants one week after transplant to encourage further basal branching. Plants should not need additional pinches or plant growth regulators if grown in the correct environment. If rising temperatures cause stretch, apply B-Nine (daminozide) at 1,500-3,000 ppm after two weeks from transplant. A Bonzi (paclobutrazol) drench at 1-8 ppm is helpful one week before plants go to sale; it will keep the plant habit tight at retail and allow normal flower development.
Pests and Diseases
Insect pests include aphids, fungus gnats, leafminers, thrips and whitefly. Disease problems can include Botrytis, powdery mildew, Pythium and Rhizoctonia. Because of calibrachoa’s high susceptibility to virus, cuttings should never be taken from the greenhouse but instead brought in from a clean, virus-indexed program. Disinfect tools used for pinching and encourage workers to change gloves often when handling multiple plant genera.
Plant collapse can occur when the media has been too saturated or kept too cold. These environmental conditions will bring in root diseases such as Pythium and Rhizoctonia.
Excessive vegetative growth without flowering is often caused by high concentrations of ammonia, high fertilization under low light levels or overwatering in cool and low light conditions.
Chlorosis is caused by an iron deficiency and can be immediately corrected with the addition of iron chelate. It also can be caused by high salt levels in the media, which can be flushed out with pure water.