Black dahlia leaves?

[Blueberry Acres]

Does anyone know why are these new leaves on my dahlia turning black? We have had a lot of Japanese beetles around; do you think the beetles caused this?
(The dahlia variety is Ferncliff Duo, if that helps )

 

[flowerbug]

have you experienced a lot of rain where you are at? to me that looks like damage from waterlogging to me...

 

[Branching Out]

I have grown dalia's for years, however I have never seen that before. Fingers crossed that it resolves itself without taking out the plant.

 

[digitS']

That's me too, @Branching Out .

Much of the West Coast is classified as having a Mediterranean climate with its characteristic low rainfall Summers. At some point as one heads north, that classification plays out to sub-arctic. We don't think of Vancouver in the same way as Anchorage but it's surprising, even to this westerner , how little rain falls through Summer months near the Pacific.

The "limiting factor" in my garden is water. Flood irrigation makes absolutely no sense for this soil. It's all sprinklers and the need to move them. Too much water is almost unknown.

Rambling but what I'm saying is that I have never thought of my dahlias as having too much water in 25+ years of growing them. Glad @flowerbug came up with that idea and hope that it is of help.

Steve

 

[Blueberry Acres]

I am in Rhode Island.
We have had a few heavy rains these last few weeks, it has been raining heavy one day per week and then dry the rest of the week. I water every night, but I water pretty lightly and I have never had any waterlogging problems.
This is the only plant with black leaves like this, the other dahlias only have a slight Japanese beetle damage.

This is my first year growing dahlias. I'm just going to watch the amount of water they are getting and hope for the best.
Thank you all so much for your help, it is really appreciated!

 

[flowerbug]

remove whatever you can just in case it is a fungal disease.

if you have others that are doing ok in that same garden then there could be some other issue just with that one plant. is the soil where they are planted rocky or heavy or does it all drain pretty well? if it is just the one plant you could also do a little digging down to see how the bottom looks.

 

[Blueberry Acres]

remove whatever you can just in case it is a fungal disease.

Ok, I will.

do a little digging down to see how the bottom looks.

Good idea, I will try that. The soil is pretty much the same throughout the garden; a bit rocky but rich and not too alkaline or acidic.
Thanks for your help, @flowerbug!

 

[flowerbug]

Ok, I will.

Good idea, I will try that. The soil is pretty much the same throughout the garden; a bit rocky but rich and not too alkaline or acidic.
Thanks for your help, @flowerbug!

i'll cross my fingers for you and hope that it is nothing more than a transitory blip. good luck!

 

[Blueberry Acres]

Update!

Everything turned out fine with the dahlias; the black went away and they are blooming now!

Thank you everybody for your help!