My dad grew dahlias in Vancouver they were hardy there but I think like gladiolas you would need to dig them and store them in the winter in our zones. His were about 6 in flowers and he had them along a fence they didn't get much wind there.

I am in zone 3 and dig up my dahlia tubers in the fall. Wait until the first frost has blackened the foliage, then cut them about 6" from the ground. Clean off the dirt, cut out the main tuber (will be spent), leave them dry a few days and store them like you would any other tuber/bulb.
I plant mine in full sun, in a protected area of the garden. I use a peony cage or small tomato cage to help support. I sometimes when my blooms get over 6-8" I drive a stake into the ground and attach it to my Dahlia. Dahlia will produce three flower buds per stem, I pinch off the outer two and the centre one gets huge. I would definitely give them a go, big pay off for a little bit of work:)
Happy gardening:)

Good question, Lynn. I need to know how to get the darn things to bloom!

I have grown dahlias for a few years now and find they do best in a sunny, semi sheltered location in the garden or pot. Start early inside and expect August bloom in zone 3. Ditto paininthepetunia. :) I also have found that they seem to bloom well with tomato fert. or fish fert. Unbeatable cut flowers as they last a long time in a vase. :)

Ginny

I don't have any problem growing them, it's storing the tubers over winter that I can't do.

Ginny, do they really get as big as they say?

I picture them similar to a peony in size, and having to use a peony ring to hold them up (???)

There are different sized dahlias. Some are little and cute and others are big and showy. None of them will bloom for me. >:(

The ones I bought one year were supposed to be the small yellow ones, instead they turned out to be the huge dinner plate variety. Boy, were those stems thick! Everyone in the neighbourhood used to say they could see my dahlias a block away. We lived in the city then and it was somewhat sheltered. I've thought about trying them here tho and see what happens. I'll try once more to overwinter the tubers.

Definately bigger than a peony, Lynn, but I've never had any reach the size of a Corningware dinner plate. More like a salad plate., :) They have very strong, thick stems like sunflowers.

Best dahlias in Canada, IMO, are from Ferncliffe. Huge selection and quality tubers although I have purchased them from Vesey's, T&T, and McFayden's in the past as well. :)

I've also grown the smaller ones and novelties from seed and overwintered the tubers.

Ginny

Ginny, the ones I saw were from Botanus, and the prices seem lower than when I looked up Ferncliff. But, maybe the size and/or type are different?

Are dahlias relatively pest and disease free?

I wonder why Marcia can't get them to bloom.......I certainly want blooms :)

Botanus too! Yes, they have some beauties this year.. :) Nadia Ruth is one I've never grown. A few years ago, I grew Night Butterfly, Blue Bayou, and another collarette that I can't remember. They were simply stunning in the back of the garden. Very rich looking blooms! :)

Ginny

I have nothing to add of my own info but found this thread that may be helpful

Here is a link that might be useful: Dahlia's won't bloom

I've been buying some for the past few years now. I get them in pots with flower buds on them already though. I get the smaller sized ones. They bloom great for me, even in part shade. I've never grown them from just the tuber, I suspect you might have to start them rather early.

If you don't want to spend a lot of money, Costco has bags of Spring bulbs in their warehouse right now; you can get a big bag of dahlia tubers for around $13. Check the back of the bag to find out what kind of dahlias they are, the dinnerplate ones are the largest flowering, both in flower and plant size. In my garden, the best spot for dahlias is next to the house, in a protected site with afternoon sun, and light friable soil. The larger ones definitely need staking - nothing more disappointing than a fully grown plant toppled over by wind.

As mentioned above, to store for the winter, just dig them up after the first frost, let them cure a bit to dry out the ends. Sprinkle them with some fungicide or garden sulphur. I wrap the tubers up in newspaper and then into paper bags or boxes and store in a cool dark location. I just checked mine and most of them are still nice and healthy. Some of the smaller ones dry up, but then that's a good excuse to buy more. :) Make sure you label them unless you like surprises.

Honalee, how early do you start yours indoors?

I usually start them as soon as they arrive, like early to mid April. I don't put them out around here until the second week in May and usually only then to the back deck where they are protected a bit until putting them in the garden. Many times they are huge! I have, however, potted directly out in early May and planted directly in the garden. They like lots of water and food.

Last year I even got some at the dollar store just out of curiousity. They grew just fine. :)

Ginny

I have grown dailias for years and they do get very big but have to be started in pots indoors up here. I even started them early indoors in southern Ont, just to get blooms earlier in the summer. They are late bloomers but will bloom until the frost takes them, so earlier planting gives you a lot more blooms.

They do need support. It's not like a peony bush at all. Mine were 4' tall and all stems had to be tied up.

if you have an unheated space (basement,garage) that does not freeze, you can keep them there. Otherwise keep them in the fridge if you have room or a spare fridge.

You can also start them from cuttings.

Hello,
I live in zone 6 and wonder if anyone has had experience leaving dinner plate dahlias in the ground over the winter ? I dug up last yr and they disintegrated ,,Not sure what happenend...so thought if I mulched well they might survive..anyone out there have experience..they are in a somewhat protected area ..
Thanks !

Our forum members are zones 1-3, but I'm pretty confident that you need to dig them up. Last year my dahlias were in big pots, and the frost got to them before I did, and the tubers were all mushy slime. I don't think they can handle any freezing at all.