
How To Grow Dahlia Seeds (Bedding Type Dahlias)
Latin name Dahlia sp. Bedding type dahlias are grown from seed and are typically short in stature. Unlike tuber-grown dahlias, these are less than 1.5 feet tall and grown as annuals from seed. Dahlias are octoploids, which means they have eight sets of homologous chromosomes; this is four times the number of chromosome pairs that most plants have. This results in a wide range of genetic expression that includes many colors and forms.
HISTORY
Native to the highlands of Mexico and Guatemala. Considered a useful edible plant in the ancient Americas for its large, edible tubers. They were not initially recognized as a particularly special plant in Europe until their full range of genetic potential was realized. This created a breeding frenzy and the dahlia was reimagined into a massive range of colors, forms, and sizes!
USES
- Beds, borders, containers, window boxes.
- Flower petals are edible.
- Seeds germinate in 7-14 days.
- Plants are best started from seed indoors 4-6 weeks before last frost date and transplanted out after all chance of frost has passed.
- Ideal germination temperature is 70-85 F.
- Plants prefer rich, well-drained soil and full sun.
- Space plants 9-12 inches apart.
- Bedding dahlias do not require staking.
- Keep plants deadheaded and well-watered and feed with a well-balanced fertilizer.
PESTS/SPECIAL CONSIDERATIONS
- If soil is not well-drained, standing water and excessive moisture can cause stem rot in dahlias. Be sure to prevent rot issues by providing well-drained soil.
- Powdery mildew can affect leaves, so provide adequate air circulation (do not space plants too closely) and water the roots to prevent excess moisture on leaves.
- Corn borers can invade the stems of dahlias. Take organic measures to prevent corn borers if they are a problem in your area.
- Dahlias are insect-pollinated and they have more homologous chromosomes than other types of flowers. This means that it can be quite challenging to ensure that the seeds you save will breed true when replanted next season. This can be fun, allowing for many interesting combinations, but if you wish to exert more control over your seed saving, you can use bagging and hand pollination techniques to avoid insects from crossing your varieties, and of course, you can clonally propagate your plants by saving the tubers.
- To save seed, allow flower heads to turn brown, collect the dried seeds and store them in a cool, dark, dry place. If your seed heads are molding, try cutting the browned flower head on a dry day and hanging upside down in a sunny window for a few days. You can extract the seeds and dry them further to prevent molding. Store seeds in a sealed container and keep in a cool, dry, dark location.