The Best of the Penn State Annual
and Perennial Cultivar Trials
Robert Berghage and Alan Michael

The summer of 1997 was an interesting and challenging season. It was cold and wet in May and June, and very dry in July with warm days but mostly cooler than normal nights. The rains returned in August, but temperatures were quite moderate. The thing that sets this growing season apart is the less than normal number of hot and humid days in July and August. In all, it was a very pleasant season for people and some plants, but the lack of heat delayed bloom in many plants and resulted in poor performance in some.

Outstanding Perennials
In the perennial garden there were a number of standouts this year. The perennial plant of the year for 1998 Echinacea 'Magnus' from Jelitto seed performed very well. It overwintered well, with vigorous new growth beginning in June. The first flowers appeared in late June and flowers continued to open into September. New flowers were bright, but the color faded with age, particularly in September. The only major problem was with Japanese beetles which damaged the flowers. This plant was very attractive to butterflies, there was almost always a Monarch or two on the blooms.

The former perennial plant of the year, Heuchera 'Purple Palace' from Jelitto seed also overwintered well and grew very vigorously this year. The large bronze leaves distinguish this cultivar from other coral bells in the garden. Also from Jelitto seed Eryngium 'Blaukappe', Digitalis 'Apricot', and Veronica 'Blue Carpet' deserve mention. They have all performed well for the 2 years that they have been in the garden. The Eryngium is an interesting thistle like plant with very attractive silver-blue stems and flowers that are extremely attractive to insects. This plant was covered with bees for most of July and August. Digitalis 'Apricot' is a spring flowering perennial with tall (4-5 ft) flowering spikes and large apricot flowers. A few of these plants died of crown rot during the summer, but the outstanding spring display makes them worth considering anyway. Veronica 'Blue Carpet' is a nice short ground cover that has spread to fill the bed quite nicely.

This spring was very good for the columbine. The 'Musik' series from Benary were outstanding, flowering heavily, with a great assortment of individual flower colors. Flowering continued sporadically into August. The cultivar 'Musik White' was particularly eye catching, with numerous bright white flowers. Several new columbines planted this year should also be mentioned because of their compact, full plant form. The 'Cameo' series, also from Benary, have not grown "lanky" like most columbine but rather have remained compact and full all summer.

Other "new" perennials in the garden this year that performed very well in their first season include the unusual groundcover Persicaria 'Dimity' and the Penstemon 'Ruby' from Blooms of Bressingham North America. 'Dimity' is an interesting low growing plant with red-tipped green leaves and pink to red flowers on 6 to 10 inch spikes. 'Ruby' produced numerous bright red flowers in August, a real showstopper. If these plants overwinter well they will be nice additions to the perennial garden. Another "new" perennial standout this year was Heuchera 'Pewter Moon' entered by Skagit Gardens. This wonderful little plant was very vigorous, yet quite compact. The thing that set it apart was the striking foliage. The leaves are red on the bottom and a mosaic of silver and green on the upper surface.

Outstanding Annuals
On the annual side there were also some real standouts. This was one of the best years in recent memory for the verbena. Verbena 'Romance Pink' and 'Romance Deep Rose' from S&G seeds performed very well, with numerous bright flowers in July and August. 'Heirloom Appleblossom' and 'Heirloom Light Blue' also from S&G and Vaughans had interesting pastel flower colors that complemented each other and would make a very nice combined planting. The one disappointment in this years verbena crop was 'Imagination', a former AAS winner which usually performs very well, but this year, presumably because of cooler weather, grew well, but flowered poorly.

It was also a very good year for the seed geraniums. The cultivar 'Mavrick Star' from Goldsmith seeds was outstanding, with vigorous growth, and good flower production. The gazania were very nice this year too. 'Daybreak Bright Orange' and 'Daybreak Red Stripe' were both vigorous and floriferous.

Many plants started slowly but finished strong. The fibrous begonia are always one of the best performers late in the season and this year was no exception. 'Victory Greenleaf Rose' from Goldsmith was one of the nicest, with an outstanding flower color and contrast with the foliage. The cultivar 'Lima White' from Samen Mauser America was one of the most uniform bedding plants I have seen. The 20 plants in the test block were uniformly floriferous and almost exactly the same size. Nierembergia 'Mont Blanc' from American Takii Inc. and All America Selections grew more slowly than usual early in the season, but as it has in the past, was an outstanding groundcover by mid to late August, and performed well right into September. The zinnia cultivars 'Profusion Rose' and 'Profusion Orange' entered by the All America Selections program were two of the most colorful plants in the garden in August and September. They were vigorous and uniform, did not suffer from any disease problems and were only slightly bothered by Japanese beetle.

The cool weather resulted in slow growth and small plants in all of the vinca, however a few seemed to be able to tolerate the cooler season better than others. The 'Cooler' series from Pan American Seed (I'm sure that's not why they called it that) although smaller than usual grew well. The cultivar 'Cooler Icy Pink' was arguably the best vinca in the garden this year.

This season also accentuated the differences between "Grandiflora" and "Floribunda and Multiflora" petunias. In general the grandiflora petunias performed much more poorly than the other types. An exception was 'Storm White' from Goldsmith which was the best white in the trials. By far the best overall petunias were the 'wave' series, 'Pink Wave' and 'Purple Wave' from Pan American Seed. These are truly outstanding plants performing well everywhere I have seen them. Of the milliflora petunias from Goldsmith Seeds the best cultivar is still 'Fantasy Pink Morn'. 'Lirica Showers Blue' and 'Lirica Showers Rose' from Sakata were interesting new petunias for this year. They have very small flowers (1/2 inch) and tiny leaves on prostrate almost woody stems. They performed well in the garden but were susceptible to iron deficiency problems in the greenhouse.

Another interesting "new" plant for the University Park garden was the Cape Daisy (Osteospermum). These plants flowered well in the spring but flowering dropped off in the summer. In the fall many succumbed to disease, with the exception of the cultivar 'Seaside' from Sakata. While plants on both sides died, these plants were still going strong in September. They produced a reasonable number of light purple daisy like flowers all season long which graced their dark green succulent foliage. This cultivar was vigorous but compact.

The most interesting new impatiens was the cultivar 'Super Elfin Sunrise' from Pan American Seed. This cultivar had spectacular unique flowers with orange centers and fuchsia edges. Tour groups in the garden were dazzled by this flower. Almost all indicated an interest in growing it in their gardens next season.

There were a number of nice cut flower plants in the garden this year. Sunflower 'Valentine' from Benary had numerous nice medium/small lemon yellow flowers on long stems. Cut flower asters of the 'Matador' series from Benary were nice double flowered asters. The cultivar 'Matador Fiery Red' for example was red with white centers on long stems. These plants flowered a bit later than other cut flower asters in the garden but they were worth the wait. Trachellium 'Purple Umbrella' was an interesting plant with nice blue/purple flowers in September that were suitable for cutting.

The 1997 growing season in Landisville was challenging for some plants, yet others performed admirably. June was dry with bright days and cool nights. July's temperatures were near normal but heavy rain fell later in the month. August was cool, averaging 30F below normal, with light rains encouraging some foliar diseases to develop. September conditions were near normal.

New, Different or Otherwise Interesting Plants
There are many new, or perhaps more accurately, uncommon plants being introduced by breeding and selection programs throughout the world. Several plants in this category performed well in the 1997 trials. All produced good flowers and foliage in containers, baskets, or beds.

The low growing white flowering Bacopa Snowstorm, a Proven Winner@, would be an excellent plant for baskets or annual ground cover. Several new Verbenas provided a colorful splash all summer in the container trial area. Bright Pink Temari, Violet Temari, Bright Red Temari, are Proven Winners from Pleasant View gardens. Blue Violet Tapien, from Bearcreek Gardens and Carpet Blue from Green Leaf Ent. were all nice cultivars. Summer Wave Totenia Violet, also a Proven Winner, was an attractive plant with violet flowers.

There were a number of daisy-like flowering plants with outstanding summer bloom, including Proven Winners, Butterfly Marguerite (Argyranthemum) and Cobbitty Daisies Summer Pink. Sanvitalia Golden Aztec, from Greenleaf was another interesting and outstanding plant. Helichrysum Golden Beauty from Proven Winners performed well in both containers and the field.

There were two nice Portulaca, both from Green Leaf Ent., Bicolor Radiance and Giant White Radiance.

For an exciting upright growing blue flowering plant for beds or containers try the newly introduced Angelonia mandiana from Green Leaf Ent. The blue flowered spreading plant scaevola has become increasing popular in hanging baskets. Proven Winner New Wonder Scaevola and the cultivar Fancy from Green Leaf Ent. performed well. The trailing yellow snapdragon Layel did well in the spring and fall. Some of these unusual plants may be difficult to find, but all are commercially available and performed well.

New Guinea Impatiens
Over the past few years breeders have introduced New Guinea Impatiens cultivars that can perform well in either full sun or shade. Flower size and flower longevity is better than ever, making this plant one of the most popular garden annuals for both containers and beds. Outstanding cultivars in the 1997 trial included a standout scarlet-red cultivar developed by Ball FloraPlant named Celebrette Scarlet. It produced a multitude of large florets, nicely displayed above its glossy green foliage on uniform vigorous plants. Shade plants tended to grow a little larger than plants grown in full sun. Celebration Rose, was an outstanding highly vigorous cultivar producing uniform displays of large rose flowers held above dark green foliage.

Other outstanding cultivars included: Paradise Timor, a compact plant whose dark green leaves provide a marvelous contrast with its intense orange flowers; Paradise Toga a medium sized plant with large pink flowers displayed well above its dark green leaves; and Paradise Samoa whose pale pink flowers and dark green foliage make it a standout in both sun and shade.

A number of other cultivars were highly rated in the trial including: Paradise Antigua, an orange flowered plant with dark green foliage that performed best in shade; Lasting Impressions Ambiance, a bicolor orange flowered plant with green and maroon foliage; Celebrette Grape Crush, intense fuchsia purple flowers contrast with dark green compact foliage; Lasting Impressions Charade, coral flowers with dark bronze/green foliage; Pure Beauty Marpesia, a coral flowered plant with glossy bronze foliage that performed slightly better in shade than sun; and Celebration Salmon a plant that is best for shade situations.

Double Impatiens
Many of the newly introduced double impatiens cultivars are vigorous and were outstanding in the shade but performed surprisingly well the sun too. Fiesta Lavender Orchid had moderate vigor with orchid pink flowers. Fiesta Burgundy Rose had an outstanding display of flowers, and although this dark colored plant developed some scorch in full sun, it recovered when the weather cooled. Fiesta White was an excellent plant in the shade and a good plant in sun, Fiesta Salsa Red was a vigorous plant, but was best in shade.

Geraniums
Poor spring growing conditions made this a tough year for the vegetative (cutting) geraniums. The best included Ball FloraPlant's Designer Lilac Chiffon which displayed good foliage and flowers even under stressful conditions. Four other cultivars, all from Goldsmith Plants, rated well: Americana Rose Splash was showy all season and produced uniform plants with moderate vigor; Americana Deep Rose was a compact plant with outstanding flowering; Americana Dark Red was compact with dark green foliage; and Americana Red was very vigorous and performed well.

Other nice zonal geraniums in the 1997 trial included a red flowered cultivar introduced by Duwaynes Greenhouse and breed by Merite, Meriflame. Even though it was slow to develop in the spring it improved greatly by mid-summer and was one of the best by season end. Americana Pink was small, but showy; Designer Purple Rose was excellent in beginning of season; and Americana Coral had a very good rating. Two Oglevee cultivars rated well, Floribunda Elizabeth and Evening Glow.

Ivy Geraniums
The best vining geraniums were the pink flowering Acapulco Compact, Red Mini-Cascade, and the salmon flowered Sofie from Fischer Geraniums, Galleria Ruby Red and the scarlet red Galleria Sunrise from Ball FloraPlant and Freestyle Pink from Goldsmith Plants.

Trailing Petunias
There are many excellent trailing petunias for use in hanging baskets, large containers or flower beds. Most are produced with cuttings, but there are a couple notable exceptions. The wave petunias Pink wave and Purple Wave from Pan American Seed have been outstanding in the trials. Standouts among the cutting produced trailing petunias this year included the Proven Winner cultivars Brilliant Mini Pink Surfinia, Purple Sun Spot Supertunia, and Blue Surfinia. The white flowered Bright Dream Petitunia, the new coral Chipper Cascadia, and Blue Spark Cascadia whose light blue flowers have delicate dark blue veins provided by Green Leaf Enterprises also did well.

The newly introduced mini-flowering petunias Cherry Pink Million Bells, and Creeping Blue Million Bells from Bear Creek Gardens were exciting because of their unique flower size. Remember petunias in containers require frequent applications of fertilizer for best performance, and most are quite sensitive to high soil pH induced iron chlorosis.

In all there were over 1500 cultivars in the garden in 1997. If you would like a copy of the full report, please write:

(Note: Feel free to use this information as desired. Please credit The Penn State Floriculture and Ornamental Horticulture Extension Program.)

Followup to the March 1998 Issue:

Waterfowl Problems in the Landscape:
There is Penn State Cooperative Extension Publication entitled Geese, Ducks, and Swans: Wildlife Damage Control No. 6. This publication discusses the available control, fright, habitat modification methods and repellents which are available to Pennsyvania residence. The publication also lists Suppliers for devices and repellents. Check your files or contact Ag Information for this useful publication.

Information provided by Rob Berghage and Jim Sellmer Penn State Department of Horticulture, Ornamental Horticulture Extension Specialist, 103 Tyson Building, University Park, PA 16802, (814) 863-2571

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