Uneven Petal Opening - Dahlia?

[GardenGeisha]

Can anyone explain to me why my dahlia bud opened petals only on the top half, toward the outside of the bud?

The bud had been so promising looking... but for some reason its petals only opened on the upper half at the outside. It looks like some of the inner ones are still trying to open, but the outer ones are already getting old and dried up looking.

The bottom ones and inside ones are still tightly in a bud and the bud looks good-- not black or anything.

I have never had this happen with a dahlia before. I've had some that had petals open all the way around only on the outside, but never on just the outer top half.

Anything I might do to further the opening process? Fertilizer? Extra water?

Are they maybe stuck shut for some reason?

 

[digitS']

It may be that the more information & experience we have with any plant, the more we realize that there is more to learn.

I have had dahlia flowers with the same problem as you have described, GardenGeisha. Sometimes, the entire plant struggles to produce a decent bloom. Sometimes, it is only 1 bud.

Why one tuber from a plant will produce blooms that look different than those from a year before, I can hardly fathom, but they do. They are clones but they "evolve." If that is right word. I am inclined to blame some things on mutations. Other problems may be a virus or some micro-organism that has invaded the plant tissue.

It may take a biopsy by a plant pathologist to diagnosis some of these problems. With about 300 dahlias, I've got quite a few things going on out there that I can't account for. Currently, the most serious concerns getting my attention is trying to ward off the annual, late summer, spider mite invasion and providing even watering for the big plants. Both of those seem to be related as the hot, dry summer days have been taxing on the plants and give the mites more of a chance to beat up on them. They like and need moist soil right now.

Sorry that I'm not more help.

Steve

 

[GardenGeisha]

Thanks for the feedback, Steve.

In another group, a Wisconsin dahlia grower responded that she is having the exact same petal phenomenon. She attributes it to the drought.

It is possible my sister did not water the pot heavily enough when I was away on vacation and she babysat the dahlia. I gave her a dinnerplate 'Maniac,' though, and it has perfect blossoms. Maybe only certain types are susceptible to this peculiarity?

 

[GardenGeisha]

I got feedback from the local Dahlia Society here. They claim this was the best year ever here for dahlias, that theirs are wonderful, and that the heat didn't bother them. They do have designated beds and timed drip watering systems for them.

So now I wonder whether the afternoon a few weeks ago when I went to church and came back home an hour later to find this dahlia on its side in the pot (the one with the weird bud that won't bloom right)is what caused the problem. The wind whipped up and knocked it sideways, but I staked it up right away, and it seemed fine-- the foliage didn't die and the buds remained good looking.

But do you suppose that could have somehow cut off the needed xylem and phloem, so to speak, causing the bud not to do right?

My sister just e-mailed that she has purple and white dahlia blossoms from those I gave her. I don't know whether she means two separate dahlias of purple and white or a variegated one. They are in much larger pots than mine.