I grow my dahlias in grow bags, and at this point most are doing quite well and are about two feet tall. I do have one dahlia plant though that looks quite yellow despite it's young age. I had a terrible problem with spider mites last season, which actually cut the season short. Could this yellowing be due to spider mites already, despite its young age? If so, is there hope for this dahlia or should I remove it from the garden and trash it? Would cutting it to the ground and starting over, accompanied by a spraying regimen, save it?

Hmmmm. Nobody? Bueller? Bueller?

If it is a virus from what I've read its trash. I know when my morning glories had thrips or mites the leaves looked more white/grayish rather than yellow. That looks like a mosaic virus to me.

Well that's a bummer.
Thanks for the reply.

If it were mine I'd give it nitrogen to green it up. It's worth a try.

I agree with both Ronnie and Arlene here. If one of mine looks like that, I attribute it to either virus, bugs, or a nutrient deficiency. You could cut it down and let it grow back, and if the leaves look like that again, I'd assume it's virus and into the trash it would go.

The only time my plants don't go in the trash with leaves like that is if we've had a sudden cold snap that borders on a frost.
Then they all have yellow tips and can show strange patterns on their leaves.
Otherwise, it's a sad day.