February 2008

Leucanthemum maximum ‘Broadway Lights’ By Paul Pilon

The Shasta daisy is one of the most recognizable perennials known to gardeners, landscapers and commercial growers. The popularity of Shasta daisies has increased further following the Perennial Plant Association's naming of leucanthemum 'Becky' as the 2003 Plant of the Year. Leucanthemum maximum 'Broadway Lights' ('Leumayel') is a recent introduction from Proven Winners that is catching the eye of both gardeners and growers alike. This cultivar offers a unique coloration of blooms opening bright yellow, lightening to butter cream and maturing nearly pure white. At peak bloom, it is covered with all three shades providing a unique and artistic appearance.

Besides its chameleon-like flowers, 'Broadway Lights' has many distinguishing characteristics, including a compact growing habit — the series can reach 18 to 24 inches in height — a long bloom time from early summer to fall, as well as attractive, coarsely-toothed foliage on sturdy stems. Additionally, retailers can market them as container plants, in combination planters, based on their attributes of attracting butterflies and deer-resistant qualities, or even for cut-flower production. This cultivar, like other Leucanthemum varieties, prefers full sun and grows well in USDA Hardiness Zones 5Ð9. In southern portions of the country, Hardiness Zones 9 and 10, 'Broadway Lights' is best when used as an annual and should be grown under partial shade.

Propagation

Leucanthemum 'Broadway Lights' is vegetatively propagated by tip cuttings by licensed propagators. Since a plant patent is being sought (PPAF-Plant Patent Applied For), unlicensed propagation of this cultivar is prohibited.

Production

Leucanthemum 'Broadway Lights' performs best when grown in a moist, well- drained medium with a slightly acidic to neutral pH: 5.8-6.4. Many commercially available peat or bark based growing mixes work well provided there is adequate drainage. Growers commonly produce 'Broadway Lights' in quart to 1-gallon containers. To promote branching, it is recommended to pinch them two weeks after transplanting. They have a moderate to moist moisture requirement; water thoroughly when irrigation is necessary, and keep them moist but not saturated during production. Plants grown too dry will often be shorter, exhibit a delay of flowering and produce fewer flowers.

'Broadway Lights' is a moderate feeder. Nutrients can be delivered using water-soluble or controlled-release fertilizers. Growers using water-soluble fertilizers apply 100- to 150-ppm nitrogen with every irrigation or use 200 ppm as needed. Controlled-release fertilizers are commonly applied as a top dress onto the media surface using the medium recommended rate on the fertilizer label or incorporated into the growing medium prior to planting at a rate equivalent to 1 to 11?2 pounds of elemental nitrogen per yard of growing medium.

Because 'Broadway Lights' is a compact variety, it is usually not necessary to control the plant height. Under certain growing conditions or under high plant densities, it may be necessary to use chemical plant growth regulators to reduce stem elongation and produce a high quality product. To a certain extent, the height can be reduced by withholding water and nutrients (provide adequate but not luxury amounts). In the northern parts of the country, I recommend applying daminozide (B-Nine or Dazide) at 2,500 ppm or uniconazole (Concise or Sumagic) at 5 ppm. Applying one to two applications seven days apart should provide adequate height control. The best results will be obtained by applying PGR when the flower stalks are beginning to elongate.

Insects and Diseases

There are numerous insects that may be observed feeding on leucanthemum, including aphids, caterpillars, foliar nematodes, four-lined plant bugs, leafhoppers, leafminers, slugs, spider mites, thrips and whiteflies. Of these insect pests, aphids are the most prevalent; thrips and whiteflies occasionally will also become problematic.

Leucanthemum are relatively disease free, and under normal growing conditions do not usually require control strategies. Growers should note that under certain circumstances leucanthemum are susceptible to numerous diseases including Alternaria, Botrytis, crown gall, Erwinia, Pythium, powdery mildew and Septoria.

These insects and diseases can be detected with routine crop monitoring; control strategies may not be necessary unless the scouting activities indicate actions should be taken.

Forcing

Leucanthemum 'Broadway Lights' can be forced into bloom out of season by following a few guidelines. It is a cold-beneficial plant; providing a cold treatment will produce more flowers per plant and provide earlier and more uniform flowering. To produce a full plant when in bloom, I recommend providing a cold treatment to plugs or small containers of 'Broadway Lights' for a minimum of six weeks at 30-40¡ F. They will flower without a cold treatment, but flowering may be sporadic and unpredictable.

Leucanthemum are considered to be long-day beneficial plants. Following vernalization, flowering will occur under any photoperiod, but long-day conditions will yield faster flowering and more blooms per plant. During naturally short days, long days can be created by extending the day to 16 hours or using a four-hour night interruption during the middle of the night using photoperiodic lighting (providing 10 foot-candles of light at the darkest spot of the production facility).

After the cold treatment and long days, the time to flower depends on the overall growing temperature. 'Broadway Lights' grown at 72¡ F will flower in as little as six weeks, while plants grown at 60¡ F will reach flowering in about 10 weeks. To produce plants with the largest flower size, most flowers per plant and a more compact size, grow them at cooler temperatures. To obtain the best quality, I recommend producing 'Broadway Lights' at 65-68¡ F, which produces flowering plants in approximately eight weeks.

Availability

Leucanthemum maximum 'Broadway Lights' is marketed through the Proven Winners (www.provenwinners.com) brand of plants. Currently, liners of 'Broadway Lights' are available from the following licensed propagators: EuroAmerican Propagators, LLC (www.euroamprop.com), Four Star Greenhouses Inc. (www.pwfourstar.com) and Pleasant View Gardens, Inc. (www.pvg.com). Finished containers may be purchased from many reputable companies across the country.