Growing Beautiful Dahlias from Seed – A Guide

Written by admin on April 11, 2020. Posted in blog, Dahlias, Growing Dahlias, Growing Guides, Propagating Dahlias, Propagation

Christmas in the Spring – Dahlias From Seed

Last year was the first year we grew dahlias from seed and I am hooked! This method of dahlia propagation is simple, and creates a great surprise in spring as the dahlia seed turn into amazing flowers. Why? Dahlia seeds are not true to the mother plant, so every seed is a new and unique variation. You never know what kind you will get! The only way to get a true replica of your mother plant is to divide the tuber, or take cuttings (Dahlia Propagation Through Cuttings article). You get such a broad and wide range of dahlia flowers from planting seed, it is truly amazing, and you can keep the variations you like, dig up that dahlia tuber, and propagate for more.

Growing Dahlias From Seed is Like Christmas in Spring

The Steps – Growing Dahlias with Seed

The dahlia from seed method is simple, and the dahlia seeds grow fast. Here is how to propagate dahlias from seed:

First off, don’t buy cheap seed! Buy some high quality Hybrid Dahlia Seed, with high germination rates. If you buy cheap seed, you’ll reap what you sow ;). You can buy what we use on our flower farm here, from a top seed producer: Hybrid Dahlia Seed.
Find a pot or seed tray and fill it with a seedling mix or a mix of soil and vermiculite.
Wet the medium and poke holes with a seed planter/dibber that are about 1/2″ deep, and about an inch or so apart.
Place your seeds in the holes and cover with soil mix.
The seeds will germinate in about 2 weeks, but if you apply bottom heat with a seed mat, it will speed up the process (This season mine popped in 7 days).
Water daily, and provide plenty of light, either with a grow light or place in a south facing window.
Soon you will have a whole set of seedlings.
Once they are about 2-3 inches or their leaves are touching, you can move them to small pots (3 inches) and continue to grow.
Before you move the little propagated dahlias to the garden, “harden them off” by exposing them to the outdoors, gradually over a week more and more.
Pro Tip – When the dahlias you grow from seed are 12-18″ tall, snip the center growth bud with garden snips/scissors. This will encourage branching and give you a bush with more flowers!
Wait for the fun!

Propagating and Growing Dahlia From Seed — Dahlia seedlings sprouting

These dahlias from seed will grow an amazing tuber you can lift if you like the variety you have produced. This tuber will produce the exact flower, and you can then use tuber division to multiply you bounty. Here is some additional info on the specific of growing dahlias and seed charateristics:

DAYS TO GERMINATE

3-5 days at 65-70°F (18-21°C)

HOW TO SOW

Transplant (recommended) – Sow your dahlia seed 4-5 weeks before last frost. Cover your seed with soil/medium and keep soil surface moist until dahlia seed emergence. When seedlings have true leaves, transplant into larger growing trays or pots. To maintain healthy seedlings, do not allow plants to become root bound and do not disturb roots during the early growing process. Direct seed in the garden – After last frost when soil is 65–70°F (18–21°C), sow thinly, 2 seeds/ft, 1/4″ deep. Cover lightly but tamp the soil. Keep surface moist, but not soaked, until emergence. Thin to 9-12″ after first true leaves appear on the dahlia plants.

LIGHT PREFERENCE

Full Sun.

PLANT HEIGHT

40-60″.

PLANT SPACING

9-12″.

HARDINESS ZONES

Winter Hardy 8-11

Annuals 3-7

HARVEST

Before dahlia blooms are completely open.

GROWING NOTES

Dahlia plants that are propagated from seeds will produce tubers that can be saved, stored and planted the following spring. In the fall, after plants have died back but before the ground freezes, cut dahlia plants back to 2-4″ above the soil line and carefully dig up the tubers and remove all excess soil. Let tubers dry and cure for 1-3 days in warm location with some humidity, out of direct sunlight with proper air flow. Pack tubers in peat moss or vermiculite inside perforated plastic bags, boxes with holes or crates.

SCIENTIFIC NAME

Dahlia variabilis