Planting Dahlia Seeds and Bulbs of Dahlia with Care Tips

Dahlia plants are true summertime standouts in the landscape. The sheer array of color, size and form make these wonderful tubers a garden favorite, both easy to grow and multiplying over time. Dahlia plants are most commonly started from tubers, but you can collect seed and increase your favorite flowers over time. You will need a little patience though, as dahlia seeds take several seasons to produce blooms, but the effort is fun and can yield some surprising results from these naturally hybridizing Dahlia plants. 

Dahlia tubers are common in nurseries and seed catalogs. They are the fastest and most reliable way to grow big, boisterous blooming dahlia flowers. Growing the dahlia flowers using dahlia seeds and bulbs may take a little more time but is a great way to extend your crop of the dazzlers. Knowing how to plant dahlia seeds isn’t hard, but there are a few tips for guaranteed success and riots of colorful blooms of Dahlia Flowers. Save your Dahlia seed for inexpensive consistent dahlia season after season. 

Dahlia plants most accurately grow from tubers which, like bulbs, are underground storage organs containing the DNA or blueprint of the plant. Vegetative methods of propagation result in true copies of the parent Dahlia plant while seeded propagation is prey to the capriciousness of nature and may result in slightly different versions of the dahlia parent. For this reason, starting dahlia seeds is not a method favored by collectors and champion breeders. 

Dahlia seeds are produced in prolific amounts on the plants, but most gardeners simply protect the tubers and replant them the next year as a surefire way to keep a favored species. However, the adventurous gardener may want to save some of that dahlia seed and see what the next season brings. It might be a bloom that surpasses its parent in beauty and form.

It can take a full season for you to get flowers on your seeded dahlias. Do dahlia seeds turn into tubers? In the first year, slender tubers will form but they will not be anything worth harvesting and will need another year or two to develop good growth nodes and produce bodacious dahlia plants. 

The first step begins with harvesting ripe, ready pods. Pods contain numerous dahlia seeds. Wait until the flower has dropped all its ray petals and the pod is a light tan-green in color. The dahlia seeds inside should be ripe and gray to dark brown.

Cut the pod off and let it dry to facilitate removal of the dahlia seeds. Separate the seed from the rest of the pod and let dry before storing it. In early spring, germinate the seeds in soilless seed starting mixture in flats. 

Sow your seeds an inch about 2.5 cm apart on the surface of the mixture and cover lightly with a dusting of the medium. Moisten the medium and keep moderately damp, moving the flats to a warm location of at least 70 degrees F about 21 C. Germination will occur in 7 to 10 days after sowing. 

Once the seedlings are large enough that their leaves are touching, individually pot them up in 3-inch about 7.5 cm containers. Harden the seedlings off Dahlia before planting them out into prepared garden beds. Wait to plant them outdoors or garden until all danger of frost has passed. 

Alternatively, you can plant them in an outdoor garden a week before the date of the last frost. In northern climates this may not give the dahlia plants enough time to develop and bloom. If cold temperatures threaten at the end of summer, repot the dahlia plants and move them into a greenhouse or indoors. 

They won’t have much tuber development, and the best way to save them for next season is to let them go dormant indoors where icy temperatures can’t damage the tiny root and tuber system of the beautiful dahlia flower. Harden them off the next season and plant outdoors. You will get big beautiful dahlia plants with plenty of appealing flowers that will set pods and start the whole growing dahlia seeds process over anew.