IN THE GARDEN: Growing Dahlias in Alaska
When the rest of your flower garden is finishing up its bloom, if you have dahlias, you are in luck because you are now witnessing multiple gorgeous colorful flowers from mid to late summer until frost.
Dahlias are subtropical plants and natives from the mountain regions of Mexico. A Swedish botanist and student of Carl Linnaeus, Anders Dahl in the 18th century had the genus dahlia flower named after him.
In Alaska, with our short growing season, special attention is needed to give these beauties a chance to reach their potential. I can assure you the planning ahead will pay off with a colorful garden at the end of the season.
Dahlias are grown from tubers for the most part. They can also be grown from cuttings and seed; however, we will be concerned with tuber growing here.
We have several growers here in Alaska for tubers. One such grower that I know of that has a love for dahlias and sells tubers is The Persistent Farmer in the Valley. Rob Wells grows dahlias in high tunnels on the Palmer side of Hatcher Pass. His website is www.thepersistentfarmer.com. Also, Misty VanderWeele is a farmer, florist, author and speaker located in Palmer at “All Dahlia’d Up”. Misty sells cut dahlias and has lots of experience in growing these plants successfully. Check out her website, www.mistyvanderweele.com. On her website, Misty gives you tips on growing dahlias and she has a PDF guide to growing dahlias in Alaska that can be purchased. This gal is definitely on fire for dahlias. Her story is very unique and interesting.
In Alaska, because of our cold soils, it is required to start our dahlias indoors in pots in February in a rich potting soil with good drainage. I like to sprinkle cinnamon on the tubers before planting to help in the prevention of fungus and diseases. Plant the tubers so that the crown is just below the surface of the soil. Planting is the perfect time to place a stake next to your plant as not to disturb the growing tuber when transplanting later outside. Water the tubers sparingly at first around the edges of the pot as dahlias are prone to rot and do not require much water to begin with. Once the dahlias start to grow up in the pots, you can begin regular watering.
Plant your dahlias outside when the chance of frost is past and the soils have started to warm. Remember to harden off your dahlias in a partially shady spot for about a week in the pots and gradually introduce them to sun so as not to burn the sensitive leaves that have been growing inside.
Dahlias like to be in full sun. Once in the ground, you will want to thoroughly water the dahlias in the morning so they dry out during the day; this will help to ward off powdery mildew. You will want to fertilize with lower nitrogen to keep from having all plant and few blooms. Look for a water soluble formula for blooms and use it every two weeks during the season. Dahlias love our long daylight and grow like crazy here.
It is hard for me to do, but when your plant is about 6-8 inches tall, pinch off the top of the plant and this helps promote a bushier plant. By pinching off the top of the plant you will get more blooms. You will also want to deadhead the blooms when they are past, which in turn promotes more blooms to form. More blooms of these flowers are definitely what you want.
Wind is hard on dahlias and will break the stalks. I had my dahlias up against the house for support and this worked well. The large blooms are heavy and need extra support and can be tied to the stake to prevent breakage. I found even a heavy rain could break my large dinner plate sized bloom stalks.
Dahlias are classified in groups according to their flower form and size. More than one dozen are recognized by the American Dahlia Association. Here are nine of the most prevalent categories:
Ball: Have spherical flowers that have blunt quilled petals, set in a spiral pattern.
Pompon: The flower is a ball type, but less than 2 inches wide usually called miniatures.
Cactus: Fully doubled flowers have narrow, pointed ray petals, quilled for more than half their length. There are two types: incurved and recurved, or straight.
Semi-cactus: Similar to cactus, the petals are broader and quilled for half their length or less.
Single: One row of petals encircles a central disk of stamens.
Anemone: Flat ray of petals surround a tightly packed tubular disk petals.
Decorative: Is a double flower and they have no central disk. The petals are broad and rounded at the ends, and they have a slightly curved appearance. They are classified as formal which is symmetrical and informal which is irregular in appearance.
Peony: Have 2-4 rows of flat ray petals surrounded by a disk of twisted petaloids.
Collarette: Have a collar of small petals that is between the ray petals and the yellow disk.
Putting your Dahlias to bed for the winter at the end of the growing season requires a little special handling. Immediately after the first frosts have darkened the foliage, cut the stem back to about six inches from the ground. In the next couple weeks, lift your tubers out of the ground carefully with a fork-like garden tool and rinse off the dirt and put them in your garage upside down to dry. Tie an identification label to the tuber so you can identify them in the spring. After the tubers have dried for two weeks, dust them with an antifungal sulfur compound or use cinnamon, then place them in a cool, dark box with cedar wood shavings, peat moss, vermiculite, or sand at 40-45 degrees. The garage is a perfect place on the floor.
In the spring, you can divide your tubers and have more dahlias and share with a friend. You will need to have one stem and it will need to have an eye in it. The new growth will come from the eye until roots form.
Once you get the hang of growing dahlias you will be hooked. The colors and their beauty make any garden a joy to behold. I hope you will give these stunning flowers a try, they are worth it!
Remember we must, “Keep Calm and Garden On”.
Chris Wood is a certified master gardener from Eagle River. Write to her at [email protected]
If you would like to put your garden in the Greater Eagle River Garden Tour on July 22, 2017 please email me at [email protected] before July 14 to add your garden.
The next Greater Eagle River Garden Club meeting will be on Tuesday, July 11, 2017 at 7 p.m. at First Baptist Church Annex behind the Brown Jug in Eagle River.
The speaker for the next meeting will be Paul Marmora. Paul will speak on “Planting a Perennial Garden.” Paul is an Alaska State Fair judge in design, plants and flowers — you may have seen his Bonsai exhibit at the fair. Paul has over 400 orchids and enjoys mounting them onto bark.
Come and join us and meet Paul!
WEED OF THE WEEK:
Garlic Mustard (see photo) is a herbaceous biennial plant. Native of Europe and found in 1868 in New York, probably brought by settlers. When crushed, this plant exudes a strong garlic odor. This kidney-shaped plant the first year has rosettes of dark green leaves arising from a common base and distinct leaves about four inches in diameter. The second year, this invasive plant grows several branched stems up to three feet tall. at the top of the plant are small white flowers with four petals. Likes low light and shade and multiplies by seed pods. Thrives in moist, shaded soil of forests, roadsides, edges of woods and also dominates the understory of the forest and decreases foraging for grazing wildlife. This pushy plant has displaced vast areas of wildflowers. If you see this in your yard, pull it up and do not put it in your compost as the seeds can last for five years.