I have about eight different dahlias, and I left every last one outside over the winter. But this one…
It was planted late last year, never did much, and I knew it wasn’t planted deep enough at the time. I did have a go at digging it out, but it didn’t want to come so I left it.
It is in a deep pot with tulips and ornamental variegated ivy (unknown variety, I found a bit on the pavement/sidewalk that had broken off from a planter, and made it mine) . The tulips did naught but one bloom this year, but I didn’t expect them to. The ivy was going crazy last year, but looks horrible this year.
The dahlia, however, looks like maybe it has a virus?
Lower leaves and stems look normal, but the budding bits of recent weeks look diseased.
So, should I chop all the icky looking parts off and hope new growth is healthy? Or is this entire plant for the bin?
Other dahlias in pots, thriving and budding within less than a foot of this one are just fine.
heretherebespiders 
I’m no dahlia expert, but that definitely looks like a virus to me. In your place I’d be hauling it out and putting it in the bin (not the compost) before it infects anything else, especially as it’s not flowering. The fact that the other stuff in the pot is doing badly too seems to indicate that whole set up is doomed… I know plant lovers hate condemning anything and will go to great lengths to bring it back, but virus is so hard to treat and puts everything else at risk.
I’ve read that it is recommended to chop their little blooms off early, to make room for good ones.
But I am one of the ones who hates to kill anything. Especially this one, hubby picked it out as it is called Akita!
The Ivy can go, no problem with that 🙂
I guess if you isolate it from the others and wash your hands and tools before you touch the others it should be safe enough. But think how awful if it spread and you lost the lot…
I am no help with this one. Some sort of leaf miner? Looks chewed and tunneled
Dad always picked off all infected pieces of plants and got them away from the others. Maybe put this plant/pot in a different location – sometimes they are just suddenly unhappy with where they are (mine go under a bush in the back corner and after a while I go check on them – sometimes fairies or something heals them….(or fear of being tossed out?)
I did chop the icky looking bits out today. Felt bad as it might not bloom again this year, but with a dahlia they don’t mind pruning really…I hope…