HOW TO GROW AND CARE FOR YOUR DAHLIAS

HOW TO GROW AND CARE FOR YOUR DAHLIAS

It’s very important that you don't plant your Dahlia tubers out too early! Dahlias thrive when the soil has warmed up and all danger of frost has passed. For Ottawa, it's usually around the May long weekend but this will change depending on your location. Store them in a cool dry place until then. 

First things first! Choose a sunny, well-drained spot and make sure the area is clear of weeds and the soil is nice and loose/fluffy. You can achieve this by using a digging fork to gently loosen the soil and remove any weeds in the area. If you can, add a nice thick layer of compost to help give your soil a boost. After you have prepared your planting area, dig a hole 4 to 6 inches deep, place the tuber parallel to the ground and cover it back up. You want to space your dahlia tubers approximately 18” apart. Since your tubers will be underground you might want to use a label to mark them so you don’t plant anything else too close.  

Tubers are very susceptible to rot when they are first planted. As long as your soil isn't bone dry, don’t water them at all until you see shoots coming out of the ground. This can take around 2-3 weeks. Once you see shoots, you should water at least once a week - more if it’s very dry and hot. To help keep the soil moist and reduce weed pressure you can also mulch around your Dahlias.

As your Dahlias grow they will need support. You can use stakes and twine or tomato cages to help hold them up as they will get very top-heavy when they start blooming. Make sure they are well supported before that windy day surprises you.

PLANTING IN POTS: You can absolutely plant your tubers in large pots. Use a pot for each tuber that is at least 12” in diameter but 18” or bigger is even better. Make sure they still have good support!

STORING YOUR TUBERS OVER THE WINTER

After the first hard frost, chop the plants just above ground level and carefully dig up and save the tubers for next spring. We use a digging fork to slowly lift the tubers out of the ground. Start digging at least 12” away from the stem because the tubers will have multiplied over the summer and will be much larger now.

After they're out of the ground you can wash off the dirt with your garden hose. Once they're cleaned off and have air-dried, you can either store them as a clump or divide them into multiple tubers, making sure each tuber has an eye. We will be posting videos on how we divide tubers to our Instagram in the fall so you can see how it’s done. Google has lots of advice as well. 

We store our tubers in vermiculite that you can usually purchase at Garden Centres. If you can’t find vermiculite, peat moss also works well. Use a cardboard box and start by putting a 2” layer of Vermiculite on the bottom. Then, lay in your tubers and separate them with layers of vermiculite so that they aren’t touching each other. The last layer should be vermiculite. When you have all your tubers packed away, place the box in a cool dark place until the following spring when you can plant them out again.