Double Play Spirea: More Than Just Pretty Flowers

As a general rule, Spiraea is known as a hardy, adaptable and attractive ornamental shrub. And of the 90 different Spiraea species, few are as colorful and useful as Spiraea japonica. The species is very hardy, 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 Spiraea, 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, Spiraea fritschiana is a low mounded, Korean native, with large, attractive blooms that are normally pure white. By pure luck I found this pink flowered anomaly in a batch of seedlings at a local university. The seed source of this plant originated in Korea and I suspect it might have been an accidental hybrid with Spiraea japonica. Pink Parasols is a low mounded plant that is much wider than it is tall, making it an excellent commercial landscape plant. 

Another observation we made early on was that most spirea are sold in the spring, well before the flowers appear. This means that the color, texture and health of the foliage is how most consumers judge the plants they are buying. Further observation revealed that some seedlings had especially good, colorful foliage when leafing out in the spring. Such was the case when we crossed Pink Parasols Spiraea fritschiana with a yellow leafed Spiraea japonica variety and came up with a number of unique, colorful hybrids. After evaluating the top selections, we introduced one and named it 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 red new growth. The pink flowers are extra-large, getting this trait from Spiraea fritschiana. The plant cultivar was named in honor of my wife Tracy, and has proven itself to be first class garden and landscape plant. Thank goodness for that, because you don’t want to name a bad plant after your wife!

Double Play Big Bang



It is amazing to note the difference in flowering between cultivars as well as seedlings. Some plants only flower in top while others flower from top to bottom. The corymb (bloom) diameter varies greatly between plants. The green-leafed varieties, Double Play Pink (Spiraea j. ‘SMNSJMFP’) and Double Play Artisan® (Spiraea j. ‘Galen’) were all selected for large corymbs and bloom density from top to bottom having pink and purple flowers respectively. Both cultivars are especially attractive in early spring as the new foliage emerges burgundy-red.  


Trialing is one of the most important parts of plant breeding. Double Play Artisan stands out from the crowd


Double Play Red® (Spiraea j. ‘SMNSJMFR’) has beautiful cherry-red spring foliage, but is was primarily selected for its uniquely colored, sangria-red flowers. It is the truest red I have ever seen in a Spirea; better than ‘Dart’s Red’, and far better than ‘Anthony Waterer’.  As the flowers age, the dark red hues do transition to pink, so there are times when the flowers will look more pink than red. Regardless, it is a truly unique and beautiful plant. 


Double Play Red (on the right) is the first true red spirea

Many gold-leaved cultivars being grown in the nursery trade are susceptible to powdery mildew (Podosphaera spiraeae). Double Play® Gold was introduced as a solution to this problem. Double Play Gold (Spiraea j. ‘Yan’) is a compact, dwarf, gold foliaged plant adorned with bright, bubblegum pink flowers. 


Double Play Gold


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. A number of 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® (Spiraea 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 Spiraea, this results in a spirea that flowers all summer long. 


Double Play Doozie spring foliage

Double Play Doozie the first ever continuous blooming spirea


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 hid the older flower heads. The flowers are a vivid dark pink making it the perfect plant to replace ‘Anthony Waterer’ a variety that should have been discontinued year ago because it is a virus infected cultivar.  

Double Play Candy Corn® (Spiraea 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 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. The name Candy Corn, pays tribute to a sickeningly sweet, American, Halloween candy noted for its bright orange and yellow colors. 


The foliage transition of Double Play Candy Corn 


There is one more spirea in the Double Play series that is not a Spiraea japonica, but rather a selection of Spiraea media, a species that is native to Eastern Europe. A number of years back we use to grow and sell a Darthauzer nurseries variety named Snowstorm™ (Spiraea 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 (Spiraea media ‘SMSMBK’) a silly, but memorable name based on the silly children’s musical instrument. I love plants with colorful foliage and 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.


Double Play Blue Kazoo foliage

Blue Kazoo planting in bloom


It is a bit humorous looking back, because so many people told us we were wasting our time breeding Spiraea. 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, with a limited number of salespeople, are looking for plants with greater impulse appeal, which will sell themselves. 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 spirea do just that.

  

Get more information on each of the Double Play varieties here