How to grow Dahlias in Zone 6

5 Tips & Tricks for Success

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Planting Tips and Tricks for growing Dahlias Successfully:
-Planting instructions that came with the Tubers.

When I saw these Orange and Purple Dahlias for Sale, I had to buy them. Also by the end of August all I have blooming in the yard are Black-eyed Susan's.
Change is Good. (smile)

How to Grow Dahlias - Instructions:

  1. Plant in spring after the last frost.
  2. If you can't plant your Dahlias outside right away, store them in a cool, dry, dark place. I just put mine in moist soil and let it sprout indoors until it's time.
  3. Dahlias do best in loose, well drained soil.
  4. Plant in groups.
  5. Plant tall varieties out of the wind, due to their height.

Light:

Full Sun to Partial Shade

Depth:

5 cm - 2"

Spacing:

50-60 cm - 20-24"

Flowering Period:

July to first Frost

Height:

80-100 cm - 32-40"

Planting:

Plant Dahlias with the crown 5cm (2 inches) below the soil surface and 50 t0 60 cm (20-24 inches) apart.
Water thoroughly after planting.

Growing:

Pinch shoot tips twice to encourage fullness, first after 2 or 3 sets of leaves have developed and again after a few weeks.
Dahlias like a lot of water.
Fertilize Dahlias regularly. I do it every 2 weeks.
Dahlias will bloom the entire summer.
Remove all spent flowers with clippers to boost further flower production. The more you cut the more Dahlias will bloom. Bouquets of fresh flowers all summer. :)

Winterizing:
Dahlias in Zone6 are annuals.

  1. Dahlias are native to Mexico and Central America
  2. After the first frost, dig up the tubers.
  3. Do not wash the tubers, but let them dry for a day.
  4. Store away from drafts at 5°C to 10°C (40°F - 50°F) in a paper bag or a box filled with peat moss or vermiculite.

Dahlias:
Summer and Fall blooming tender perennials

Dahlias come in many forms and colours.
Single flower dahlias - Semi-doubles, Anemone, Cactus, Balls and Pom Poms (less than 2" wide).
Most dahlias grow from 2'- 6' tall and many spread just almost just as wide. Dahlias are hardy in Zone8-11.

Dahlias from Seed:

I have done this and I found it a lot easier than growing from tubers.
With seeds; I just start my seeds indoors or direct sow outdoors in the spring.
At the end of the summer I start dead-heading and saving the dahlias seeds.
I dry my seeds, cure and store for another year.
They bloom heavily the first year and produce tubers, If you want to save them.
They bear semi-double to double 2-3" flowers and grow up to 1 foot tall. These dahlias are much easier to grow than their taller relatives.

Growing dahlias in Canada can be a rewarding experience, as these vibrant flowers thrive in the Canadian climate.
Here are some steps to help you successfully grow dahlias:

  1. Choose the right location: Dahlias require plenty of sunlight, so choose a location in your garden that receives at least 6-8 hours of direct sunlight per day. Additionally, ensure that the soil is well-draining to prevent waterlogging, which can cause root rot.

  2. Prepare the soil: Before planting, prepare the soil by loosening it to a depth of about 12 inches and adding organic matter such as compost or well-rotted manure to improve drainage and fertility.

  3. Planting: In Canada, dahlias are typically planted in late spring, after the danger of frost has passed. You can plant dahlia tubers directly into the ground or start them indoors in pots several weeks before the last frost date and then transplant them outdoors once the weather warms up. Plant the tubers about 6-8 inches deep and space them about 12-18 inches apart, depending on the variety.

  4. Watering: Keep the soil consistently moist, but not waterlogged.

  5. Fertilizing: Dahlias are heavy feeders and benefit from regular fertilization. Apply a balanced fertilizer, such as a 10-10-10 formulation, every 4-6 weeks during the growing season to promote healthy growth and abundant blooms. Worm tea and compost works as well.

  6. Staking: Taller dahlia varieties may require staking to support their stems and prevent them from flopping over. Install stakes or tomato cages at the time of planting to provide support as the plants grow.

  7. Pest and disease control: Keep an eye out for common pests such as aphids, slugs, and earwigs, as well as diseases like powdery mildew. Maintaining good air circulation, proper spacing and avoiding overhead watering to minimize these problems. My problem are mostly slugs and snails.

  8. Mulching: Applying a layer of mulch around the base of dahlia plants can help conserve moisture, suppress weeds, and regulate soil temperature. Use organic mulches such as shredded leaves, straw, or wood chips and apply them after the soil has warmed up in the spring.

  9. Enjoying the blooms: Finally, take the time to appreciate the beauty of your dahlia garden throughout the growing season. Cut flowers for bouquets to bring indoors, share with friends and neighbors and don't forget to shake the critters out after cutting them for making bouquets. Dahlia flowers can last up to a week in a vase.

  10. Regular Maintenance: Staying on top of regular maintenance tasks such as weeding, pruning, and removing spent foliage and blooms keeps your dahlia bed looking tidy and reduces the risk of pests and diseases.

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