Hi linlily. It's my very first time to grow Dahlias. I have planted some in the ground and some in the 18" and 20" flower pots. They are doing so well and are blooming now. I live in northern MD.

Thanks for your response, riamitchell. About how deep did you plant the tubers? And did you plant one tuber/plant per 18 inch pot?

Linda

Hello linlily. I planted each about 4" deep in each flower pot. So far some of them have started blooming.

It does depend on the dahlia size. I have Harlequin (8-10" tall) zinnias in 4" pots and they do OK. They do better in 8" pots.

For taller dahlia, like the photo above, I'd go 12" absolute minimum, 18" preferable.

And yep, 4" deep is great. I find that the Harlequin do well at the surface, larger dahlia do better a bit deeper--I usually plant around 2" to 3" deep, but 4" really is a better idea to make it more sturdy.

Since, like me, you can't leave them out for the winter, depth won't matter for freeze protection. You can store the entire pot for the winter if you want (I've had great luck doing that in the cellar) and just put outside and moisten a bit when temperatures rise in May.

I think I've been planting them too deep. I was planting the really tall ones in the beds, not in pots, 6 inches. These are ones that had already budded but did not have leaves. After planting them, some never came up any further.

Thank you both for your suggestions on how to plant in pots. I appreciate it.
Linda

Naw, you're fine planting six inches deep in the garden, the soil goes down a lot further.

How deep I plant depends on the dahlia, again. Harlequins have the crown at the surface, but I start those from seed and simply follow what the plant decided to do. When I tag and store the ones I want to keep, they go deeper the second year.

Taller dalia vary. My Sky Angel probably gets planted four inches deep, but it's an established dahlia (that really should be split again). The ones I added this year (Blue Boy and Color Spectacle) were put nearer the surface because I planted late and the tubers had noticeably weakened. I didn't know I needed them until I realized the canna tubers had given up due to age!

Since I remove promptly after first frost, going deep isn't necessary--but I could if I wanted.

I tried growing many larger sized dahlia plants in 16-18" pots 2 years ago, without good luck. They simply became dwarfed. The plants grew much shorter than they would have in the ground. They grew thinner and less healthy looking, and the flowers were 1/2 the size they had been the year before grown in the ground. I think you can get away with growing dahliettas in pots, and maybe small dahlia plants, but the larger plants that get to 4 feet tall or taller will not do well in pots....

Many plants dont do well in pots, in spite of claims made by many people.

well, you can always plant in pots, and then bury the pots in the ground, to give the pot extra support. Makes them easier to dig and separate in the fall if you live where ya gots to dig every year. Gallon containers work well â¦

dave