Are dahlias perennial in Canada?
Dahlias are annuals in Canada, but perennials in warmer climates. If you truly love a certain Dahlia (it happens) you can gently dig up the tuber after the first hard frost, and replant next year. Dahlias grow best when they receive a consistent supply of water. Drip irrigation is ideal, as it directs moisture to the root zone while keeping the foliage dry. If you are hand-watering, it’s best to water deeply once or twice per week.In my zone, 7b, i usually start planting dahlias in late april/early may, but i’ve also done plantings as late as mid-june. Find a sunny, well-draining spot in your garden, and place your tubers 5-6 inches in the ground, with the eye facing up, and space them apart about 12-18 inches or so.Dahlias rank high on the list of plants that dislike weather extremes. They prefer temperatures that vary no more than about 20 degrees: 70-80°F during the day and 60-70°F at night. When temperatures rise above 85°F or nights don’t cool down, dahlias may begin exhibiting signs of stress.Making sure the plants have adequate sunlight and water also helps to ensure blooming. Water dahlias in the garden once or twice a week, depending on the amount of rainfall and heat. Apply bloom-boosting fertilizer that is low in nitrogen and high in phosphorus for more flowers.In most areas outside the warmest regions of the United States, dahlia tubers must be dug up and stored or covered before the cold season. In previous years, we’ve always uprooted our dahlias and kept them indoors for the winter. Now, we cover the entire bed with burlap and a thick layer of hay.
How to overwinter dahlias in Canada?
Cut back the entire plant to 4 – 6 inches. Keep the dahlias in their pot over winter. Keep the pot in a cool, dry, dark place that doesn’t freeze. Dahlias are tropical plants. They are native from southern Mexico to the northern Andes Mountains. They can tolerate temperatures NEAR freezing, but anything below 40°F can damage new, tender growth. A frost usually kills the above ground parts.Planting Time Follow the same instructions as winter storage — keeping the tubers properly hydrated in a cool, dark place. Dahlia tubers that are planted in September will flower during November and December.Yes, you can leave your dahlias in pots over the winter but you will need to make sure they are protected from the cold. Cut back your plants, relocate your pots to a frost-free garage or shed for the winter and allow the compost to dry out completely.The tubers of dahlias will tolerate a light frost, however, they will not survive a hard killing freeze. A killing frost or freeze occurs when temperatures are below 28 degrees for a duration of hours or days, whereas a light frost may only be a couple of hours of temperatures below 32 degrees.As fall rolls in, it’s time for many of us to start digging up our dahlia tubers. Why? Because if they’re left in the ground in colder climates where the soil freezes, your tubers will turn to mush. If you’re in a warmer region, you might be lucky enough to leave them in the ground all year.