Dahlia Seed Saving and Genetics E-GUIDE

DAHLIA SEED SAVING + GENETICS

E-GUIDE

INTRODUCTION TO DAHLIA SEED SAVING

Are you aware that dahlias have the incredible ability to be grown from seed? It's a fact that many gardeners are only familiar with growing dahlias from tubers. However, it is through the process of growing dahlias from seed that new and exciting varieties are first brought to life. These varieties are then made available for purchase as tubers, ensuring that consumers receive true-to-type blooms.

But here's the exciting part - home gardeners like yourself can embark on this journey too! In my very own flower garden, I experienced the joy of nurturing various dahlia forms, each boasting distinct flower shapes and sizes. From open-centered marvels to charming pompon and anemone flowered beauties, I
relied on the natural pollination by bees to assist in the breeding process.

As the blooms eventually fade away, and the seed heads reach maturity, I eagerly collect the seeds. With anticipation building, I patiently wait until spring arrives to plant these seeds, watching as new and exhilarating varieties begin to emerge! The possibilities are boundless, and I cannot wait to see what enchanting surprises lie in store for us next spring.

All about Dahlias!

Dahlias, a magnificent member of the Asteraceae family, are known for their global presence. Spanning across continents, these plants are true wonders of nature. What makes dahlias truly fascinating is the unique anatomy of their bloom.

Botanically speaking, each dahlia flower is considered a composite because of the anatomy of
their bloom, which is, botanically speaking, a composite of individual flowers
called florets. These individual florets, form a breathtaking spectacle. With two distinct types of florets - the vibrant ray florets and the potent disc florets - dahlias captivate both our eyes and the pollinators. While the ray florets entice with their vivid colors, they serve primarily as petals, signaling in our pollinators with their vibrancy. On the other hand, it is the disc florets that hold the key to life. These fertile wonders of nature can produce seeds, bringing forth new life with every successful pollination!

Dahlia Genetics/ DNA

When you leave a dahlia flower on the plant, it will eventually go to seed. The flower head will create a seed pod that will produce seeds that you can then grow the following year. Each seed contains it’s own DNA and will grow a new and unique variety. These seed pods are typically harvested at the end of the growing season to allow the seed heads to fully mature and produce ripe seeds. Then after harvesting the seeds, you store them over winter and grow them the next spring.

Dahlia flower seeds get their genetic makeup from the seed parent as well as from the pollination of bees. That’s right, the bees and other garden pollinators actually play a huge role in determining what your dahlia seeds will eventually grow. The bees carry pollen from one dahlia plant to the next and actually modify the genetic make-up of the dahlia seeds. Most open pollinated dahlia seeds will grow single or semi-double blooms with an open-center. Many breeders will either eliminate open centered dahlias or hand pollinate their dahlias to increase their chances of producing a fully double dahlia.

Open
Pollination

My approach to gathering seeds from my dahlias this year was a straightforward strategy of embracing open pollination. By allowing our local bees to freely pollinate the available blooms, we ensure a vibrant and diverse array of seeds with no further effort on our part. The unique form of a dahlia bloom can greatly impact the number of pollinators it attracts. Some dahlias, with their open-centered design, provide easy access to their disc florets, enticing pollinators and resulting in bountiful and viable seeds. On the other hand, double-flowered dahlias may not be as enticing to our buzzing friends due to their less visible disc centers. As a result, our open-centered varieties often steal the show, captivating both bees and garden enthusiasts alike.

While most of the bees were indeed attracted to the open-centered varieties rather than the double-flowered varieties in my garden, we can still harvest bountiful seed from our more sought after, closed-center beauties. Leaving the flowers on their plants will allow them to open a bit more and you can remove inner petals to make their centers more accessible for pollinators. Of coarse, the open-centered blooms will always attract more pollinators, because of this, the pollen the bees will be spreading does tend to produce seeds with plants that have open-centered forms. Although I do keep good distance between my trial seedling garden and my dahlia tuber plots (with many flowers between to knock off open-center pollen), I can still expect that the majority of seeds saved will grow be open center varieties. By selecting seeds from our double-flowered varieties, we can at least ensure that one of the parent plants is a double-flowered variety, giving us our best chance to end up with a closed center seedling. We can only hope for those few and far between that will bring forth new and exciting double-flowered varieties that will be the next craze...and that is the excitement of dahlia breeding!

Collecting
and Storing Seeds

Collecting seeds from dahlias is typically done in the fall once the plants bloom and seed heads have entirely dried up. If pollination has occurred, you will find tiny, dark bottle-necked-shaped seeds within the seed head that can be stored immediately. Seeds can also be collected from seed heads that haven’t completely dried up,
yet the flower has been pollinated. This is our common practice since we are in a climate with high humidity. Often-times our seeds start to rot before they ever have a chance to fully dry out. In this case we clip the stem at least 6" below the forming seed head. We let them lose all petals and begin to close up while on the plant, but we can cut them early and allow them to further ripen in a vase of water indoor where the humidity is better controlled. If the seed head is firm when given a gentle squeeze, check for the presence of mature seed that can be dried out, and then stored in a dry, dark, and cool place.

Germination
and Transplanting

In the spring, dahlia seeds can be sown indoors 4-6 weeks before the last frost. Plant dahlia seeds ¼” deep in seed starting medium and keep evenly moist until germination occurs. Once seedlings have 1-2 sets of true leaves, they can be transplanted outdoors
in a well-drained location and full sun. Plants started by seed will
produce tubers that can be dug up in the fall and stored to be planted again in the spring. Typically it takes seedlings 120 days to fully produce viable tubers for use the following year, so start as soon as possible! SHOP OUR DAHLIA SEEDS HERE!

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