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GROWING GLORIOUS DAHLIAS
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Dahlias were so popular back in the 1920’s and 30’s. They come in so many shapes, sizes, and colors that they deserve a prominent place in modern day gardens. An elderly gentleman I knew had a very tiny front yard. He filled the space between his porch and the front sidewalk with dahlias, large and small. It was pretty spectacular. Growing Glorious Dahlias provide great rewards!
These blooms are often grown to display in flower shows. Judges and everday gardeners alike are in hot pursuit of the perfect bloom. Dahlias come in cactus, peony, anemone, stellar, collarette, and waterlily shapes, and more. From the ten inch “dinnerplate” dahlia blooms to the 2 inch lollipop-style pompons, the variety seems endless.
“Midnight Dancer” and “Orange Julius” were my first attempt at growing dahlias. The rich purple combined with the orange and yellow blend were a knockout when planted together. My current favorite is a pink dahlia called “Fascination” with dark colored foliage.
Dahlias mix well with other flowers and make great cut flowers. AND they are edible!
HOW TO PLANT DAHLIAS
- Some folks start dahlia tubers indoors in containers a month ahead of time to get a jump start on the season. If you go this route, don’t use a potting soil that is mixed with fertilizer. It burns them.
- Don’t rush to plant them outside. Wait till all danger of spring frost is past. Planting time will probably be a little after the tomato plants go into the ground.
- Dahlias should be planted in well-drained soil to prevent rot.
- Try to find a sunny location that has some protection from the wind.
- The soil should be rich, so amend it with sand, peat moss, and/or compost. Do not fertilize at planting time. If you can’t add amendments to the soil, just go ahead and plant them in regular garden soil.
- Do not plant dahlia tubers that are wrinkled. Discard them.
- When planting, each tuber must have at least one “eye” (a pink bud) or a piece of the crown (green growth) attached or it will not develop. The eyes are located at the base of the stem.
- The planting hole should be slightly wider than the root ball of the plant. Dig a hole 6 to 8 inches deep. For tall dahlias, dig a 12 inch deep hole.
- Plant tubers with the growing points, or “eyes,” facing up. Cover with 2 to 3 inches of soil. As the stem sprouts, fill the hole in gradually with soil until it is at ground level.
- Tall dahlias that produce large flowers will require support. Dahlia stems are hollow and fairly brittle so do not skip this step. Place stakes in the ground at planting time and tie stems to them as they grow.
- Do not water right after planting. This could make them rot. Wait till the sprouts appear. Then water. If you are experiencing a drought, water very sparingly at planting time.
SPACING DAHLIA PLANTS
- Bedding dahlias can be planted 9 to 12 inches apart.
- Smaller flowering types usually grow about 3 feet tall. They should be spaced 2 feet apart.
- Tall, larger-flowered dahlias should be spaced 3 feet apart.
If you plant tall dahlias about 1 foot apart, they make a flowering “hedge.” And the plants will twine together and support each other.
Dwarf to medium sized dahlias do well growing in containers. If they get bigger than expected, and you think they need more light, you can move the containers around.
Dahlias start blooming about 8 weeks after planting, starting in mid-July.
CARING FOR DAHLIAS
Dahlias have very quirky personalities:
- The more sunlight you give them, the more they bloom.
- BUT, the more fertilizer you dump on them, the less they bloom. It will all start to go into leaf production.
- They love the sun, especially morning sun, yet they don’t care for heat and humidity. Unfortunately, this takes in most of the U.S.A.
Sometimes plants, like people, are just plain hard to please – – – still the reward far outweighs the bother.
- Weed by hand. Don’t use a hoe or shovel or you might injure the tubers.
- Do not mulch! This attracts slugs. Plus, dahlias like the warmth of the sun on their roots.
- Overwatering causes rot. After the plants are well established, you can start watering them. A sprinkler system is preferable. If not, use a sprinkle can, but don’t dump lots of water on them at once. Add water, give it time to soak in, then add more. Water more frequently in hot climates.
- Shake the water out of the blooms after a rain or it might weight the plant down.
If you prune your plants they will get bushier. This increases the number of stems, and therefore, will multiply the number of blooms.
- Pinch out 3 to 4 inches of center growth when the plants are 1 foot tall.
- For larger blooms, choose the largest bud in a cluster, and remove 2 smaller buds.
- Bedding dahlias don’t need staking or disbudding. Just pinch out the growing point that shoots up from the middle of the young plant. This will encourage bushiness.
- Deadhead flowers as they fade.
- The more you cut dahlias, the more they will bloom.
- Cut the stems in the morning before it gets hot. Put them in a bucket of cool water. Remove the bottom leaves when placing the flowers in a vase. Bouquets should last about a week. Possibly a little longer if you add a bit of sugar to the water.
The Aztecs used dahlia tubers as a food crop. Peeled, then steamed, boiled, baked, fried, or even hash browned, each tuber has its own flavor. Some have a taste that is a combo of potato and radish, others might taste like asparagus or fresh parsley. Some have a smoky flavor.
Nevertheless, some plants taste far better than others. Some varieties are bitter, bland, or else are so fibrous when cooked they aren’t worth fooling with. You simply have to experiment.
Late in the season, the amount of blooms will decrease, and you know winter is nigh.
- Dahlia foliage blackens with the first frost. When this occurs, wait about 10 days before you dig them. This helps the tubers to go dormant.
- In the northern states, lift the tubers and store them indoors during the winter.
- Shake the soil off of the tubers. Cut out any rotten parts. Leave the clumps outside in sun for a few days to dry.
- Pack them away in boxes in the basement in loose material: Vermiculite, dry sand, or peat moss. Cover the box loosely. You may need to sprinkle the tubers with water during the winter if they look too dry.
- Store in a well-ventilated, frost-free place: 40 to 45 degrees is ideal, but 35 to 50 degrees will do.
- Many people consider this to be too much bother. You can always just buy new plants in the spring.
- Dahlias are hardy to Zone 8. In the southern states, they can be cut back and left in the ground to overwinter. Cover with a deep mulch.
“Bishop of Llandaff” Dahlia produces small, intense scarlet flowers with dark burgundy foliage.
“Thomas Edison” Dahlia comes close to the color of my beloved “Midnight Dancer” variety, which these days is rather hard to find. “Thomas Edison” is a rich reddish purple with 10 inch blooms.
“Bodacious” Dahlia is an 8 to 10 inch “dinnerplate” dahlia. Red orange blooms have yellow petal tips and undersides. It has a strong similarity to the “Orange Julius” variety that I used to grow, which is also hard to find now.
“Zorro” Dahlia is an incredible red flower measuring over 10 inches across.
“Lambada” Dahlia has rosy pink outer petals, and a creamy center. A bit of rosy red is in the “heart.”
“Santa Claus” Dahlia is a “shaggy” red and white combination. It produces 6 to 8 inch blooms. Some people think it reminds them of a pinwheel.
“Fascination” Dahlia is my all-time favorite! It is a RHS Award of Garden Merit winner. Rich rose pink flowers that can get 4 to 5 inches across cover the plant. The petals are “twisted,” which is very unusual. The foliage is dark colored, and combined with the color of the flowers, this dahlia is hard to miss. It grows 2 feet tall.
HAPPY PLANTING! Susan