WELLINGTON COUNTY – Dahlias are easy-to-grow plants that provide beautiful, prolific flowers and they come in a rainbow of colours.
From waterlilies to pompoms, big double flowered dinnerplates to dainty single flowers, there is a flower style and colour that you will love.
Even just a couple of dahlias tucked into your growing space will give you an abundance of dazzling flowers from late summer and through the fall until the first frost arrives.
But did you know it’s possible to get dahlias to bloom earlier?
To get a head start, tubers can be pre-sprouted indoors to get flowers 5 to 6 weeks earlier.
Pre-sprouting requires three things: damp potting soil, warmth, and a light source such as a bright window, sunroom, grow light, or a greenhouse that can be kept above freezing.
You can wake up your tubers six to eight weeks before planting time.
You can use small pots or an 11 x 22 inch standard tray available at most nurseries and a clear plastic dome (or cover the tray loosely with a piece of bubble wrap).
You are trying to keep the moisture level even during this process.
Write the variety name on each tuber with a Sharpie.
Put damp (not wet) potting soil roughly ¾ inch deep in your tray or pot as tubers rot easily.
Lay your tubers on top of the soil on their side, then sprinkle more potting soil to cover them. The tubers should be covered up to the crown end where the tuber sprouts. Put the clear dome over the top and place the tray in a warm spot in your house.
Waking up tubers can take between two to four weeks. They do not sprout all at the same time.
At this stage they need warmth, not light. If the potting soil starts to dry out, use a spray bottle to mist the soil so that it remains damp at all times.
Blooming – Dahlias can be forced to bloom early. Guelph-Wellington Master Gardeners tell you how. Submitted photos
Once the tuber has sprouted a 1” sprout, it’s time to pot them up (if not already in a pot).
Use the smallest pot that can fit the tuber, on its side, such as a 3-4” pot.
It’s not necessary to use a 1 gallon pot.
Smaller tubers start producing roots faster than just living off a fat tuber full of starch reserves. This also helps to conserve space.
If your tuber is long, cut it to fit in your pot, allow the cuts to dry for 24 hours, then pot up.
Once the tubers have sprouted, keep the pots under bright light to avoid stretching.
Plant small dahlia plants out once the lilacs bloom or after our last frost date (around May 11).
Plant in holes 4-6” deep. Put in a stake of suitable height for the fully grown plant.
If you have tubers that haven’t been pre-sprouted, plant the tuber on its side with the eye/shoots close to the stake about 6” below the surface after the last frost.
Then sit back and enjoy!