Seeds, Fertilizer, Varieties
Peonies come in many colors and symbolize beauty, honor, wealth, and romance. They are a wonderful gift for any occasion.
Tulips come in a variety of color choices and are a spring favorite. They also represent fertility, charm, and love.
It has been a fruitful summer full of blooms across the Seattle area — peonies, roses, hydrangeas and other bushels of bursting, bright flowers filling our garden beds and street corners.
And while the official start of fall is right around the corner, and many blooms have, well, already bloomed, you can still see one last flower in abundance — dahlias.
There are more than 50,000 registered varieties of dahlias, and right now, plenty of the flower’s 20 distinct forms and sizes can be seen in peak bloom around the Seattle area, said Roger Walker, co-president of the Puget Sound Dahlia Association.
Dahlias are a late-summer bloom, bringing up the rear of most flowers’ peak season and lasting, in some cases, through October (or until the first frost arrives).
They thrive in Seattle’s milder summers and boosted humidity, which is one of the reasons the city named the perennial its official flower nearly 110 years ago.
The flower, which is typically planted in the spring with warm season crops like annual flowers or vegetables, is a tuber, just like a potato. Tubers are short and thick underground stems. With feeder roots, tubers allow the plant to take in, process and store water and nutrients from the soil.
It’s an “easy-care plant,” only needing “sun, water and good soil,” according to the dahlia association. Its blooms range from a petite 4 inches to the size of large dinner plates.
“The good thing about dahlias is that you can just grow a few to add color to your garden,” Walker said. “Or you can go hog wild and become an exhibitor, a judge and even a dahlia hybridizer striving to develop new varieties. There’s something for everyone.”
Walker said he particularly loves the variety of shapes, sizes and colors of dahlias.
They’re also “fairly easy to grow, although crazed exhibitors spend much more time grooming them than the casual gardener. But even for the most casual gardener, dahlias are forgiving and will put on a great display given minimal care,” he said.
When Seattle named the dahlia its official flower, the city’s park board “agreed to make an extensive showing of these flowers in the various parks of the city,” according to an April 16, 1914, story in The Seattle Daily Times, now The Seattle Times.
Today, Seattle’s most abundant display of dahlias is at Volunteer Park, said Rachel Schulkin, a spokesperson at Seattle Parks and Recreation.
The Volunteer Park dahlia bed is maintained by the Puget Sound Dahlia Association, which also manages beds at Big Rock Park Central in Sammamish and the Bellevue Botanical Garden.
The dahlia association, established in 1976, is one of North America’s largest dahlia organizations with over 200 members, according to Walker.
The Bellevue Botanical Garden bed has moved “a couple of times as the garden evolved,” Walker said, landing on its current “prime location” this year.
Walker recently hosted a walk through the garden, showing guests the bed of 150 to 200 dahlia plants, which change from year to year, he said.
“We try to plant varieties that appeal to the public,” Walker said. “You’ll see variegated and bicolored varieties that may not do well in stuffy show competition, but are favorites in the garden.”
As for his own favorite variety — “I’m not going there,” he said. “There are no favorites.”
Here’s where to find dahlias in bloom in the Seattle area:
Bellevue Botanical Garden
One year after the Bellevue Botanical Garden opened to the public in 1992, the Puget Sound Dahlia Association installed the first dahlia display on the grounds. The dahlias in the bed change every year, and the association plants varieties that appeal to the public. Guests can view up to 200 dahlias at the garden. 12001 Main St., Bellevue; 425-452-2750; bellevuebotanical.org
Big Rock Park Central
Big Rock Park Central is a 20-acre park located in the heart of Sammamish. The park includes dense forest cover, open meadows, a stream, trails that navigate through the property, and, of course, a dahlia bed maintained by the Puget Sound Dahlia Association. 1516 220th Ave. S.E., Sammamish; 425-295-0585; sammamish.us/our-community/recreation/parks-trails/big-rock-park-central
Point Defiance Park
Tacoma’s Point Defiance Park includes a range of attractions, like the Point Defiance Zoo & Aquarium, Five Mile Drive and Trails, Owen Beach and the park’s various gardens. Point Defiance Park’s Dahlia Trial Garden is one of the largest official trial gardens in the U.S. and Canada, maintained in partnership with the Washington State Dahlia Society.
The garden includes tubers sent by dahlia growers from the U.S., Canada, England, New Zealand and Australia. Each year, the dahlias are scored by American Dahlia Society judges. Dahlias receiving between 85 and 100 points are included in the society’s annual classification book. They are then named and become available to the general public, according to Metro Parks Tacoma. 5400 N. Pearl St., Tacoma; 253-209-5806; metroparkstacoma.org/place/dahlia-trial-garden
Volunteer Park, located in Seattle’s Capitol Hill neighborhood, features plenty of permanent landscaping and even a conservatory. From July through the first frost, dahlias bloom in abundance in the Puget Sound Dahlia Association bed, which members have been planting annually since 1984. 1247 15th Ave. E., Seattle; 206-684-4075; seattle.gov/parks/allparks/volunteer-park
If you’ve grown your own dahlias this year, here’s what to do when the first frost arrives and some tips for the upcoming season. Plus, advice for anyone who wants to start fresh in the spring.
Fall: To dig or not to dig?
- Digging and dividing tubers every other year will keep your dahlias healthier.
- The dahlia association recommends lifting and dividing tuber clumps in late fall. Wait two weeks after a frost has killed the foliage to let the tuber harden and cure, then dig up, brush off and store the tuber in a cool spot like an unheated garage or porch that is 40 to 50 degrees.
- You can divide now or in spring with a sharp knife and keen focus. There’s a swollen part of the tuber where it meets last year’s stem. You need a piece of this to ensure the tuber will have an eye (growing tip). Check on your tubers in storage monthly to make sure they are looking good.
Spring: Location and planting
- The dahlia association recommends planting only when the days get warmer, which is usually early May in the Seattle area.
- Choose a well-drained location that gets at least six hours of sun.
- Mix in compost to the area before planting. When temperatures are reliably over 60 degrees, plant the tuber 4- to 6-inches deep on its side with the eyes facing upward. If desired, apply slow-release, organic fertilizer with a lower nitrogen level (the first number in a fertilizer ratio), such as 5-10-10.
- Promote good air circulation to sidestep powdery mildew by placing each tuber at least 24 inches apart. Set your stakes when planting.
- In Western Washington, don’t water until you see growth above ground.
- If snails are roaming, consider protecting your plants with a solid cloche or sprinkling Sluggo Plus as needed.
- If keeping in the ground through winter, add 4 inches of compost in fall or spring.
Summer: Care and plenty of cut stems
- Watering is key, especially between July and September, for abundant flower production. A deep soaking two or three times per week is best. For a large bed, it may take up to 1 hour.
- Pinch the growing tips off the central stalk when the plants are about 24 inches tall, cutting above the fifth leaf from the ground, to encourage stronger stems, robust branching and more flowers. If you see an earwig, don’t worry — they won’t do any serious damage.
- Reapply fertilizer after one month.
- When the flowers come, cut, enjoy and repeat! Pick bouquets in the morning when it’s cool. Cut stems longer than your forearm, above a leaf, and plunge into water right away.
Information from The Seattle Times archive is included in this report.