Growing Dahlia’s From Seed
The drama queen of the flowers, the Dahlia. These tropical beauties are a staple in the garden and require little effort for big lush blooms.
Dahlias have been spotted across the globe in their history with their birth place being largely placed in the mountain areas of Guatemala and Mexico.
They get their common name from, Andreas Dahl, a Swedish botanist.
One of the most enchanting aspects of dahlias is their incredible diversity. They come in thousands of colors, shapes, and sizes, making them suitable for various garden styles and design preferences.
Dahlias are commonly grown from a potato-like tuber, that behaves very similarly to most bulbs. In spots like Vancouver (Zone 8), you can actually keep them deep in the ground over winter and they’ll spring up again once the sun is out.
Did you know?
When growing dahlias, the tuber is almost guaranteed to look like what the adult flower looked like. For example, if you plant the tuber of a pink dinner-plate, you will almost surely get a pink dinner-plate flower.
However, when you plant dahlia seeds, the resulting flower is typically NOT similar to the flower you harvested seeds from. This is why there are thousands of dahlia varietals. Each flower head can result in new blooms!
This is also why dahlias are a favourite among most gardeners.
HARVESTING DAHLIA SEEDS
One of the great things about dahlias is their cut-and-come-again nature. The more you cut them, the more they’ll produce blooms. The key thing with cutting them is to cut deep down the stem. Count 4-5 leaf shoots from the bottom and cut right above the 5th leaf. These deeper cuts tell the plant to grow healthier, stronger, stems.
Without proper cutting and deadheading, dahlia flowers can get very tall and “lanky”. Their stems get thin and will often break or fall over.
However, the season will eventually come to a close and the plants will stop producing flowers and will redirect their energy to their tubers (this happens closer to late October).
To collect dahlia seeds, let the bloom die and remain on the plant instead of deadheading. The flower head will turn from bloom, to what looks like decay, and then a precious seed pod.
A dahlia flower during bloom, and as a seed pod.
Keep the pod on the plant until it is fully brown and crispy. If you pull it off too soon seeds won’t develop. From here, you can pop the seed head into a brown paper bag or break it open to harvest the seeds yourself.
The seeds themselves are sandwiched in between the petal-like sheaths of the flower head.
Here you can see the small, flat dahlia seed in between the seed head sheaths.
From here, you can plant the seeds in late winter/early spring in containers indoors to kick start your growing season. And then watch the magic unfold as the tiny seed becomes a potato-like tuber, and then rockets into the sky with great colour.
If you want to learn more about collecting seeds from plants of all kinds, join the Garden Guardians! We meet every Wednesday and Saturday morning to garden and learn together in the fields.
Don’t have the time? We’re also hosting a seed-saving class and seed swap this season as well. I’ll be going over the ins and outs of proper seed collecting, breeding, collecting the best kinds of seed, and all other insider tips!
