February 2019 Plant Trials

Walters Gardens: Summer Trial Highlights By Vaughn Fletcher

One of the most significant and exciting developments in the past few years has been the participation of perennial breeders in the summer trials programs. This increased presence is the result of intensive perennial breeding from global companies culminating in many outstanding introductions. This competitive environment is reflected in the plethora of current and new perennials entered in the summer trials.

The breeding and marketing program at Walters Gardens has accelerated with the Proven Winners partnership in 2011. Proven Winners, in conjunction with Walters Gardens, has an extensive and rigorous trialing and selection process for perennials which has culminated in the introduction of dramatic and cutting-edge varieties.

This article focuses on current and new Walters Gardens
introductions in the two-year beds at Metrolina in North Carolina and Colorado State University trial last summer. I visited both trials on multiple occasions in early and late summer to observe and evaluate summer performance. The performance criteria include floriferousness, durability, new colors, flower stability, disease and insect resistance, and growth rate.

ACHILLEA ‘SASSY SUMMER SANGRIA’

This is a new Sassy Summer Collection variety for 2019. The
series is comprised of five colors characterized by dense dark green feathered foliage and a strong upright architecture. The bicolor Sangria was in the North Carolina trial, and was eye catching with its dark red flowers and white eye. The flowers are positioned nicely above the foliage. It matures to 30 to 36 inches making it an excellent addition as a midsize variety for perennial gardens. This vigorous series is hardy to Zone 3.

AGASTACHE ‘ROSIE POSIE’

This variety has been in the summer trials the past two years and for good reason. It has been one of the most floriferous agastache varieties with stunning two tone plumes of hot pink flowers with magenta calyxes. It begins to bloom in early summer and continues through early fall. This variety is densely compact and matures to 18 to 24 inches. It is hardy to Zone 6 and in all trials was a butterfly magnet. We have many outstanding varieties and colors in the market and this variety may be unparalleled for its flower power.

BUDDLEIA ‘MONARCH PRINCE CHARMING’

We are familiar with the cultivated species of Buddleia davidii and many additional popular garden cultivars. In the past 10 years, we have seen the development and introduction of new series and collections that have compactness, seed sterility, unique stable colors and improved panicle size. Consumers are attracted to these
varieties for many reasons including drought and heat tolerance, and especially as an important pollinator for hummingbirds and bees and a butterfly magnet.

Walters Gardens has three buddleia collections in the program: Cascade, Humdinger and the Monarch series. Prince Charming, the newest addition to the Monarch collection, was in the summer trials. It was the most distinctive and stunning buddleia in the trial because of its panicle size, coverage and breakthrough raspberry pink flower color. This variety has a tight, spreading, upright habit maturing to 4 feet and is hardy to Zone 5. This series is impactful and striking and explodes with color as the summer progresses.

HIBISCUS ‘SUMMERIFIC HOLY GRAIL’

This Proven Winners introduction for 2019 is an eye-catching, hardy hibiscus. The Summerific Collection includes six varieties. Holy Grail was in the Metrolina trial throughout the summer and was striking with dark, almost black, non-fading foliage and bright green calyxes complemented with large, deep-red flowers. It was spectacular and will be a definite winner in retail programs. This variety will mature at 48 to 54 inches and is hardy to Zone 4. There are many hardy hibiscus with unique solid and multicolor flowers to choose from, and this is a summer-fall flowering plant and worth waiting for!

HIBISCUS ‘SUMMERIFIC CHERRY CHOCO LATTE’

This Proven Winners variety was in the Colorado State University trial last summer and fall. I saw it in late July and returned in mid-September when the plant was mature and flowering prolifically. It is part of the Summerfic Collection and was stunning with its large multicolored flowers. The white flowers with the pronounced pink veining and red eye were extraordinary. This variety replaces Cherry Cheesecake in the Proven Winner portfolio. The improvements include larger flowers, darker foliage, compact habit and a more conspicuous flower venation. This variety matures at 44 to 48 inches and is hardy to Zone 4.

LEUCANTHEMUM ‘SUPERBUM CREME PUFF’

We have an abundance of outstanding Shasta Daisy cultivars in
the perennial market and many were in the summer trials last year.
Walters Gardens has a total of eight in the 2019 program including two Proven Winner varieties. The variety I am highlighting is Creme Puff, which was introduced two years ago. I saw it in early June and later in August in North Carolina. What impressed me about this variety was the tight, compact growth habit, heat tolerance, large white flowers with overlapping petals and a pronounced gold center. Many Shasta Daisies can be unsightly in mid to late summer with numerous spent flower heads, but this variety, with its prodigious flower canopy, created a mass of color that was stunning in the perennial bed. This is a low growing variety that matures at 14 to 16 inches and is hardy to Zone 5.

PEROVSKIA ATRIPLICIFOLIA ‘BLUE JEAN BABY’

When I worked in the retail sector in early 1980s, the number of perovskia varieties was limited to atriplicifolia and a few other selected varieties. Even through 2010 the offering was minimal consisting primarily of atriplicifolia, Filigran, Little Spire, Longin and Blue Spire. Since then, the breeding, trialing and introduction of new vegetative and seed varieties has been monumental and impactful. We now have cultivars from multiple breeders that offer different sizes, forms, and varied hues of blue.

I want to recognize ‘Blue Jean Baby’, which has been trialed at Colorado State and other trials the past few years and never disappoints. It has been most impressive, characterized by its floriferousness, vigor and upright habit maturing at 30 to 36 inches. The lavender-blue flowers with contrasting purple calyxes are eye-catching. This variety has excellent application in landscape settings where a strong upright accent plant is required. It is hardy to Zone 4 and, as with all perovskia, it is drought tolerant, aromatic, low maintenance and provides outstanding color mid-summer to early fall.

MONARDA ‘SUGAR BUZZ ROCKIN’ RASPBERRY’

Walters Gardens offers multiple monarda series including the Leading Lady, Pardon My and the Sugar Buzz series. There are eight
colors in the Sugar Buzz series, and Rockin’ Raspberry was in the
southern summer trial. It was in color in early June and more mature and floriferous when I saw it again in mid-August. This variety
manifested the qualities inherent in the series: vigor, dark green foliage, vivid colors and mildew resistance. Rockin Raspberry was stunning with its deep raspberry flowers. It is hardy to Zone 4 and matures at 18 to 20 inches.

MONARDA ‘ELECTRIC NEON PINK’

This is a new standalone interspecific introduction for 2019. This variety was unusual because of its mounded, glossy foliage and
large, fluorescent two-tone neon pink flowers which were so colorful
positioned above the canopy. The flower color is unique for Bee Balm, and Walters Gardens is planning to introduce more varieties to
augment this series. This variety is hardy to Zone 4a and matures at
20 to 24 inches.

PHLOX ‘FASHIONABLY EARLY FLAMINGO’

This variety was distinguishable from other series in the trials by its dense, stoloniferous habit and earliness to bloom. I was impressed by the flower coverage and glossy, mildew resistant foliage of this variety. The deep lavender-pink flower clusters were prodigious and dramatic and showed no indication of mildew throughout the summer. This relatively new series is comprised of four colors that mature at 28 to 36 inches and are hardy to Zone 4. This series has
a long blooming window and has demonstrated some reblooming potential in early fall.

Walters Gardens is focusing on new colors, forms, extended
flowering period, stronger architecture, improved flower stability, and most importantly programmability to meet the demands of the producer and ultimately the consumer.