The photo is not at all clear but that appears to be an insect issue, not a disease. My guess is ninebark aphids (yes, these shrubs have their own species of aphid!).

Heres better new photo…

thank you!

Okay thanks! I’ll try spraying with water first…

I just washed my ninebark 'diabolo' the other day, The aphids were so thick on a few stems, they were stunting the new growth. I went over them again this AM and found a few places that I had missed.

NEVER.. and i mean.. NEV ER ... cut stuff off... and then ask us .. lol ..

i cant think of one thing to do with a shrub.. that would cause you to give it a haircut ... crikey... put down the shears and walk away ...

but.. if you repeatedly have trouble with the same plant .. year after year.. just get rid of that plant... lifes to short ...

when i moved to 5 acres.. and hundreds of shrubs.. i got a little more zen about every plant looking perfect.. and if 5 or 10 f them looked like carp any given year.. so what.. and odds were extremely high.. it wouldnt happen again next year ...

even a damage green leaf can process sunlight into energy ... so why cut off half the plant.. just because of a few spots ... or whatever ...

so say it with me.. ohhhmmmmmm

ken

Ninebarks can be pruned back routinely with no ill effects. It can even be hard pruned down to around 6 inches if desired but that should have been done in very early spring.

I have a few diablos. never noticed an aphid issue.

ken,

I generally agree, but there are times when you have to cut back. Like when moving a gigantic shrub that otherwise couldn't be moved without herculean efforts. Or if you have to paint something stems are growing against.

i do prune them in early spring and remove some of the older canes. Maybe it’s wrong, but once its done flowering around now I always prune off the long flowering branches that sort of run into each other.

Mine has only been in for two years and I've never pruned it but it's nice to know that I can.

I was limited to where I could plant it because of the existing landscaping so I'm sure I'll be cutting it back where it sticks through the stair railing, eventually and probably to have clearance in front for the lawn mower.

If that is a Diablo, it will hugely outgrow that spot. And it won't be happy trying to fit into it.

I think Laceyvail is right…gonna get too big there. If you can’t move it, follow what gardengal has said above regarding hard pruning in early spring.

Do you mean it will hang out over the lawn? I know it's a bit too close to the stairs (3ft.?) but it's over 6 feet away from the house.

And why does everybody call these diablo? Mine is diabolo. :-)

eta:

Here's a little better pic.

"And why does everybody call these diablo? Mine is diabolo. :-)"

And both are considered accepted usages, one as the registered trademark name. The actual cultivar name is 'Monlo'.

The mature size of this selection is 10' by 10', or more. Unless heavily pruned going forward, I'd say there is a serious space issue to be considered in that location.

Okay, I see.

The plant was purchased to replace a purple leaf sand cherry that declined. The customer (dw) wanted something in that same color range and what do I know? So you could call this a 'trial'.

If it doesn't work out, maybe a dwarf version of this one or something else will go in it's place.

Any ideas of what maroon/purple leaf shrub or small tree might work better in that location?

I do have the northern climate and sandy ground on my side as things don't get quite as big, quite as fast as they do further south and east. And she does want it tall enough so she can see it some when she looks out the bay window.

Thanks for the information.

;-)

Just FWIW:

The diabolo turned out to be about what we were looking for. Yes, there will be some pruning necessary, probably starting next year, but that's fine.

After I washed the aphids off a few times, I neglected checking on the plant any further until yesterday, when I checked, they had disappeared altogether. :-)

7-4-23:

Just any update:

The shrub will eventually need some pruning as time goes on.

I guess I'm glad it's too big instead of too small.

DW thinks it's perfect right now, need I say more? ;-)

eta: I just looked and can't see any aphids on this plant at all, this season.

< shrug > .

Looks great! Mine are doing well as well!

Your recent post won't show replies since you linked it to Name that Plant FAQs. I believe it's Physocarpus, Ninebark in that post.

Carol-Thank you i removed the FAQ. p

It still doesn't work and shows no replies. Physocarpus opulifolius (Ninebark): Minnesota Wildflowers

I see everything fine on this thread.

What am I missing??

It is this thread that is the issue: https://www.houzz.com/discussions/6385707/what-am-i-mystery-shrub

I posted to it as well. I can see my comment but apparently no one else can. And yes, it IS a ninebark, Physocarpus.

Weird, I can see my comment but not yours GG....:-?

Thank you all for your expertise! Yes, my question was posted elsewhere but for some reason wouldn't show responses. We did not know that Ninebarks came in a different color!

My MIL lost one and didnt know what it was.

9-11-2023:

Looks like I will be cutting this back some next spring. It actually grows out away from the north side of the house, reaching for sunlight.

;-)

My experience with mine is that they grow much larger than what was initially said. Probably too large for your space now…need more of a dwarf variety that wont block your door. They are a beautiful shrub but they want a lot of room. I’d trim it back now so opens up your entry. Mine dont seem to care when I trim….

Thanks!

I trimmed those back, sticking out into the stairs over a month ago. They're back! ;-)

I thought I'd wait until the leaves are off so I can see what I'm doing.

If nothing else, the Stihl 250 will make short work of it, but I'm thinking of just cutting out some of the larger main shoots at the bottom.

Cutting higher on the branch doesn't seem to slow them down at all.

The neighbor next door has one that must be a dwarf, it's about half the size of mine and older.

It's simply too big a plant for the spot and hacking at it to keep it smaller won't ever look good. Or be effective for long.

Thanks!

There's one down the street that's just as tall as mine but not as wide. It is a Columnar or fastigiate?

Or do they prune it somehow?