July 2007

Comparing Argyranthemums By Ryan Hall

Pacific Plug & Liner has hosted a stop on the California Pack Trials for the last five years. Each year, Pacific Plug & Liner has used these opportunities to show a comparative grow out of a certain genus that has mass appeal to our industry. For 2007, the genus argyranthemum was grown. Argyranthemum, more commonly known as Mar-guerite daisy, is a staple landscape plant in California and most of the West Coast. Although most argyranthemum will grow into woody sub-shrubs in milder climates, most are still grown and sold as annual items.

Trial Details

For comparison, Pacific Plug & Liner looked at more than 50 varieties to see what stood out in a crowded market. All the varieties are commercially available as unrooted cuttings or rooted liners. Unrooted cuttings were stuck week 47, and rooted liners were transplanted week 50. Two weeks after transplant, all varieties received a pinch midway down the stem. When the plants were pot full, they received a 2-ppm pactrobutozol drench. After the PGR treatment, 50 percent of the plantings were placed outdoors, and the remaining 50 percent were left inside the greenhouse to grow on.

California growers, especially those closer to the coast in a Zone 9 climate, start and finish their argyranthemum crops outside. This is common for most growers finishing premium cool-crop annuals such as osteospermum. The one clear result from our trial regarding production turned out to be growing the crop cool was key to finishing a quality plant. Although California's coastal climate is drastically diff-erent than many other areas of the country, the basic culture for growing a cool crop of argyran-themum is the same if applied in the greenhouse. Any grower that has success growing osteospermum should be able to have sim-ilar results with argyranthemum.

When grown cool with a single pinch, almost all of the varieties in the trial finished very nicely. There was no clear winner or superior variety overall. The results are subject to the desired use of the variety. The trial showed many strong selections; however, there were very few complete series that showed good uniformity and color range.

Madeira Series

If any series from one breeder could be considered a true series, it would be the Madeira series from Ball FloraPlant. The breeding originates from Australia and proves to be one of the most uniform and well-rounded color ranges available. The Madeira Crested forms were the most uniform in the group: Crested Pearl, Crested Lemon and Crested Yellow showed almost identical habits, flower size and timing. In general, this series had medium vigor with a well-branched habit. This series is ideal for 1-gal. production where growers are looking for a nice color selection that can be grown side by side and shipped on the same schedule.

LaRita Series

Selecta First Class varieties have always had a strong showing in our comparison trials. Best known for its calibrachoa Mini-famous series, Selecta continues to add to its extensive list of vegetative annuals. LaRita is a newer series to the market. Although limited in its color range, the LaRita series showed controlled habits ç with good selections in each color class. In general, this series tended to be one of the most compact in the comparison. Any grower doing high-density production or looking for an argyranthemum ideal for a 4-inch program should try the LaRita series. One standout color that proved to be unique was 'LaRita Lime', a very light-yellow, single-flowered selection.

Summersong And Comet Series

Ecke Ranch has been a strong player in the argyranthemum market for some time. The selections from Ecke mainly composed of one-off selections and smaller series. The double-flowered Summersong series showed well. 'Summersong Rose' proved to be one of the most florif- erous varieties on a vigorous plant that could easily finish a 1-gal.

container and would be ideal for larger containers such as 10-inch cache planters. 'Summersong Primrose' also showed to be a nice compliment to Rose.

When looking for a strong single-flowered selection, 'Comet White' and 'Comet Pink' both showed very well with large, single flowers and well-matched habits. Two one-off selections that stood out were 'Galaxy Orchid' with a unique, bicolor, double flower and 'Sole Mio', a very nice crested-type dark-yellow flower on top of well-branched blue-green foliage.

Courtyard And Molimba Series

Proven Winners along with Ecke has had one of the nicest selections of argyranthemum cultivars in the market for some time. Best known for 'Butterfly', Proven Winners has added to this tried-and-true selection with many other series and selections. The Courtyard series had a standout selection called 'Courtyard Buttercream', a dark-yellow crested type similar to Ecke's 'Sole Mio'. 'Courtyard Buttercream' was one of the first varieties to show color and kept flowering throughout the trial. Also from Proven Winners is the Molimba series featuring Syngenta breeding. 'Molimba Mini Yellow' was an excellent compact, single, yellow selection.

Shere Series

The Shere series from Syngenta is some of the newest breeding in the trial. Shere varieties are available through the A Cut Above program from S&G Flowers. Shere mainly consists of single-flowered, white selections with a few unique yellow selections as well. Shere varieties, in general, showed to be very uniform selections with compact to medium vigor ideal for 1-gal. production. 'Shere Maggy Parachute White' has unique drooping petals on a compact habit. 'Shere Semi-Double White' has clean, white, crested-type flowers on a very compact and well-branched form.

Angelic Series

While most series had a high concentration of white and yellow selections, the Angelic series from Danziger "Dan" Flower Farm had one of the highest amounts of red and pink selections.

In general, Angelic varieties tended to have more medium to vigorous habits, ideal for 1-gal. and larger containers. However, some of their new selections proved to be nicely compact and controlled in growth habit. 'Angelic Snow' and 'Angelic Lemon' are two new selections with crested-type flowers on compact habits. 'Angelic Purple', 'Angelic Pink Silk' and 'Angelic Pink Improved' are all fully double forms with colors ranging from light pink to dark magenta. These three selections proved to be very well matched and would be ideal for larger container production such as 10-inch cache planters.

Overall Trial Results

Overall, most of the trial selections proved to be very nice varieties. Almost all of the selections branched nicely with a single pinch and grew well with a controlled habit when finished cool. Most selections have a strong single white, the most common color for an argyranthemum. However, there is still room for more color breakthroughs, including truer reds and more flower types.

Pacifc Plug & Liner always welcomes suggestions for future comparison trials.