As we approach June and onset of summer, it is time to highlight one of the best flowering trees for our local area, the Dogwood. These trees brighten up our landscapes in May and June with some serious flower power and offer additional interest in summer and fall, with showy berries on many and striking fall colors on all. Traditionally, the Dogwood represents the onset of spring in many parts of the country, and although the vernal equinox for us is in the rear view mirror, we now get to enjoy these later spring blooming specimens.
The genus Cornus contains everything Dogwood in the plant world, including some useful PNW native groundcovers and shrubs, and some larger growing impressive species like Giant Dogwood (Cornus controversa) and Pagoda Dogwood (Cornus alternifolia) - all worthy of any gardener’s consideration. The main species available to gardeners are below, and keep in mind numerous cultivars of each can be found at local garden centers.
Pacific Dogwood (Cornus nuttallii and cvs.): These are PNW natives and can often be seen amongst mixed forests both West and East of the Cascades in our State. They are tall, stately trees with extra-large white flowers in May followed by nice fall color. However, these are a bit susceptible to Dogwood Anthracnose (which we will discuss shortly) in our wet spring weather this side of the mountains.
Eastern Dogwood (Cornus florida and cvs.): These are native to the Eastern US, and in all honesty are what most folks think of when they picture a “Dogwood” tree. They sport the classic rounded, four-petal flower in either pink or white and also have excellent fall color. I would never say these cannot be grown successfully in our area, but typically the healthier ones I see have full sun, good air circulation around them, and are probably sprayed regularly as these are more prone to Anthracnose than any others in our rainy spring weather.
Korean Dogwood (Cornus kousa and cvs.): These lovely Dogwoods have more of a star-shaped flower with pointed petals and offer pink and white options as well. They bloom a bit later through June and even into early July, then develop bright little red fruits in summer to fall, and finally shine with reddish fall color. These are extremely resistant to Anthracnose and easy to grow in the landscape.
Rutgers Hybrids (Cornus x and cvs.): Rutgers University has been kind to all gardeners, spending the last 40+ years developing useful hybrids for home gardens with superior flower power and improved resistance to Anthracnose. There are numerous worthy cultivars here for our area, giving us excellent flowers and the disease resistance of the Korean Dogwood.
As mentioned above, the major issue in Western Washington’s wet spring climate is Dogwood Anthracnose. This disease often infects dogwood trees in wet spring weather, causing the tips of foliage to curl and discolor. If not treated, Anthracnose may cause younger twigs to dieback - which eventually affects flower bud production and kills branches. As with almost all plant diseases, remember that air circulation and exposure will always help, but on occasion some may need to be sprayed a bit to control this issue.
All Dogwoods can take a little more “wet”, tolerating heavier soils, and are great options for those who have fought (like me) Verticillium Wilt from less than ideal drainage. They are slower growing specimens and bloom on old wood, so bud set occurs over the summer each year, which in turn open into flowers the following spring. Ideally any pruning should be done right after flowering, although dead wood and structural issues can be corrected over the winter as well. These are not drought tolerant so be sure to irrigate trees a bit in dry summer months, keeping them happy and thriving to ensure bloom the following year. Dogwoods are not heavy feeders by any means, but a dose of quality organic fertilizer this time of year will help optimize flower bud production.
The choices out there for specific cultivars and hybrids of Dogwood, like with most plants these days, can be somewhat overwhelming. Any variety of Korean Dogwood is excellent and should minimize disease, as will any of the Rutgers hybrids (for exactly the same reason). A few of my favorite specific varieties are listed below…
‘Venus’ and ‘Starlight’: These are two superior Rutgers crosses of Korean and Pacific Dogwood, both with cleaner foliage and larger white blossoms in May into June. They grow a little more upright and larger than others, eventually reaching about 25 feet tall and 20 feet wide. Venus was the choice for me almost 20 years ago in my own yard, and it has been a trouble-free spectacular specimen year after year.
‘Stellar Pink’: Another Rutgers hybrid, blooming pink from May into June with the rounded petals like Eastern Dogwood and the disease resistance of Korean Dogwood. Grows to about 20 feet tall and wide with age, and if you can find it, the variegated form is excellent with white and green foliage adding more interest in partial shade.
‘Morning Sun’: Speaking of variegation, this is one of the best to me, with bright yellow on green foliage and a white star-shaped flowers from June into July. Tidy habit to about 15 feet tall and wide, and will take some shade for best foliage color. An excellent Korean Dogwood option.
‘Scarlet Fire’ and ‘Rosey Teacups’: Two of the more recent introductions from Rutgers University, both simply stunning in flower. Each sports clean foliage and grows to about 20 feet tall and wide with age. ‘Scarlet Fire’ has rich deep pink flowers, while ‘Rosey Teacups’ has a nice medium pink color.
‘Milky Way’: One of best traditional white Korean Dogwood, sporting a bazillion smaller white star-shaped blooms in June, and then showy little red fruits in the fall. Grows to about 20 feet tall and wide over time and has nice reddish-burgundy color in the fall. This literal galaxy of flowers is quite impressive indeed in any landscape.
‘Heartthrob’: An excellent Korean variety introduced in Oregon, with nice medium pink flowers that last into July. These have a busy habit to about 20 feet tall and wide, and foliage turns bright reds in the fall. Another oldie and goodie for sure with excellent disease resistance.
I would invite all gardeners to explore the realm of Dogwoods. Visit your local garden center and speak with a Certified Professional Horticulturist about your site for help in selecting the perfect tree for your yard. These magnificent trees are sure to bring you a lifetime of enjoyment, just as my ‘Venus’ is in the process of doing for me.
