Dahlia Flower Bloom. Since we plant ours in April ours will start blooming around 90 days after planting which is around mid-July. Mar 12 2021 Dahlias are mid-to- late season flowers that come in a vast array of colors and forms from small bedding dahlias to plate-sized blossoms atop 6-foot stems.
This will encourage more blooms. Most varieties grow 4 to 5 feet tall. Oct 22 2019 Rowe says Dahlias typically bloom in sets of three and the center bud will bloom first.
Depending on where you live that could mean that you can have dahlias in bloom for three four or even five months.
The flowers will continue to bloom through the fall up until the first frosts. However depending on your hardiness zone dahlias can hold up reasonably well in winter. When they are in full bloom cut flowers frequently for bouquets. Plant dahlias tubers in the springtime when the ground is warm enough about the same time you would plant your vegetable garden.