Plant of the Month—Double Play® Spiraea

By Tim Wood, Spring Meadow Nursery

As a general rule, spirea is known as a hardy, adaptable, and attractive ornamental shrub. And of the 90 different spirea species, few are as colorful and useful as Spiraea japonica. The species is very hardy and adaptable and offers a wide range of flower and foliage colors. Add to this the ability to cross with other species and you have an array of breeding opportunities.

With spirea, as well as other species, observation and imagination are the first steps in plant breeding, so looking for and noticing things that others may miss, brings new opportunities.

One of our early discoveries was a rich, pink-flowered Spiraea fritschiana that we named Pink Parasols® (‘Wilma’). Known for its excellent hardiness and attractive autumn foliage, S. fritschiana is a lowmounded Korean native with large, attractive blooms that are normally pure white. By luck, I found a pinkflowered anomaly in a batch of seedlings at a local university. I suspect it might have been an accidental hybrid with S. japonica.

Further observation revealed that some seedlings had especially good, colorful foliage when leafing out in the spring. This is especially useful because spirea is typically sold in the spring, well before the flowers appear. So the color, texture, and health of the foliage are how most consumers judge the plants they are buying.

Such was the case when we crossed Pink Parasols with a yellow-leafed S. japonica variety and came up with a number of unique, colorful hybrids.

After evaluating the top selections, we introduced Double Play Big Bang® (Spiraea x ‘Tracy’). The spring flush of foliage is a vibrant orange. As the foliage matures, it turns bright yellow with contrasting new red growth. The pink flowers are extralarge, getting this trait from S. fritschiana. The plant cultivar was named in honor of my wife, Tracy, and has proven itself to be a firstclass garden and landscape plant. Thank goodness for that, because you don’t want to name a bad plant after your wife!

Double Play Doozie® is a groundbreaking non-invasive spirea, the first of its kind. Its lack of seed also makes it a perpetual bloomer, putting all of its energy into creating wave after wave of red-pink flowers from early summer through frost. Ask for it from your preferred wholesale nursery.

• Red spring foliage • Sterile • Compact • Quick to produce

5' DOUBLE PLAY DOOZIE® Spiraea x ‘NCSX2’, pp30,953; cbraf USDA Zone 3-8, full sun, part sun 2-3' tall and wide

Available from these suppliers:

Bennett’s Creek Nursery Smithfield, VA • 757-483-1425 Buds & Blooms Nursery Brown Summit, NC • 800-772-2837 Cohansey Nursery Bridgeton, NJ • 856-453-4900 David’s Nursery Exmore, VA • 757-442-7000 Eastern Shore Nursery of VA Melfa, VA • 757-787-4732 Fair View Nursery Wilson, NC • 252-243-3656 Hope Grange Nursery Bridgeton, NJ • 856-491-5204 Huber Nurseries Manheim, PA • 717-898-9115 Latham’s Nursery Monroe, NC • 704-283-5696 Marshall’s Riverbank Nurseries Salisbury, MD • 410-677-0900 Piedmont Carolina Nursery Colfax, NC • 336-993-4114 Riggins Nursery Bridgeton, NJ • 856-455-2459 Sepers Nursery Newfield, NJ • 856-691-0597 Shreckhise Nurseries Grottoes, VA • 540-249-5761 Spring Run Farm Coatesville, PA • 610-380-1402 The Ivy Farm Locustville, VA • 757-787-4096 www.provenwinners-shrubs.com

Another in the series is Double Play® Red (S. japonica ‘SMNSJMFR’). It has beautiful cherry-red spring foliage, but it was primarily selected for its uniquely colored sangria-red flowers. It is the truest red I have ever seen in a spirea.

While most of the plants in the Double Play® series were developed by Spring Meadow in our internal breeding program, two varieties were developed by North Carolina State University. Several years ago, we had funded Dr. Thomas Ranney’s plant breeding team to develop sterile cultivars of potentially invasive plants.

One of the common methods for sterile varieties is to create a triploid (3x) plant, which has three sets of chromosomes instead of the normal two, a diploid (2x). This was the technique used to create seedless watermelons. The process starts by treating young seedlings with colchicine or oryzalin, which doubles the chromosomes, thus creating a tetraploid (4x) plant. The tetraploid plant is then crossed back with a normal diploid plant. The resulting triploid seedlings are often seedless. Double Play Doozie® (S. japonica ‘NCSX2’) is a seedless triploid as well as a wide cross containing genes of more than one species. One of the added benefits of seedless plants is that they put their energy into flowering instead of setting seed. With Double Play Doozie®, this results in a spirea that flowers all summer long.

This plant is a game-changer in the landscape market because it is so easy to grow and because it looks just as good in flower in August as it does in June when it first flowers. There is no need to shear it to get it to rebloom. The new growth continues to produce flower buds and flowers that cover and hide the older flower heads. The flowers are a vivid dark pink, making it the perfect plant to replace ‘Anthony Waterer’.

Double Play® Candy Corn® (S. japonica ‘NCSX1’) is another Tom Ranney triploid hybrid, but it is not noted for being a rebloomer. This plant variety was selected for its unique colorful foliage. In the spring the first flush of foliage emerges a fiery orange-red. As spring progresses, the foliage color changes to a bright yellow and then eventually

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to a butter yellow, while constantly being accentuated with bright reddish-orange hues in the new growth. The color combination is quite unique and pleasing.

There is one more spirea in the Double Play® series that is not a S. japonica but rather a selection of Spiraea media, a species that is native to Eastern Europe. Some years back we use to grow and sell a Darthauzer nurseries variety named Snowstorm™ (S. media ‘Darsnorm’). After three or four generations of inbreeding and selection, we singled out a dwarf plant with notable blue foliage. We introduced it with the name Double Play® Blue Kazoo® (S. media ‘SMSMBK’) a silly but memorable name based on the children’s musical instrument. I love plants with colorful foliage, especially blue foliage, and I believe this is a special plant. It is a low-mounded beauty with waxy, blue-green foliage that is randomly air-brushed with a cast of purple hues. The large white spring blooms contrast wonderfully with the richly colored foliage. Like all spirea, it looks best when planted en masse.

It is a bit humorous looking back because so many people told us we were wasting our time breeding spirea. They said, “Who needs another spirea?” But, like all plant breeding, there is always room for new plants if they are improvements. Growers continue to look for plants that finish faster and that have fewer production inputs. Retailers, having a limited number of salespeople, are looking for plants with greater impulse appeal. Consumers want shrubs that offer more than just two weeks of flowers. They are looking for reliable plants that earn their keep all season long, and these new Double Play® spirea do just that.