here in our MI ... weve had a very hot summer.. with some good drought up until the last few weeks ...

im seeing a lot of leaf damage across ALL PLANTs i see driving around.. and its not really telling me anymore than its september in MI after a bad summer moisture wise ...

soooo.. dont freak out.. and be leery of any treatment this late int eh year.. especially on deciduous plants .. its better to invest in cleaning up all the fallen leaves.. rather than using chemicals on leaves that fall off.. this time of year...

i never grew a single boxwood.. go figure on that.. so im not fluent with box disease ... nor even if your are deciduous or not ...

the fear you are living.. is partially a function of planting a monoculture... if one gets sick.. you have the potential to lose them all .. so... you lived this box dream.. but if ..AND WHEN .. the project goes south.. dont keep replacing them with more box ... forever ... move on to other things ...

with recent transplants.. and drought.. a non fully established plant can show leaf damage late in the summer ... so your watering protocol may have been a bit deficient ... but almost good enough.. if you get my drift ... if this isnt disease.. keep them well watered.. deep into november... and hopefully by next spring.. they should be mostly self sufficient.. unless there is another august drought. ... in if so.. give them a long deep trickle drink in mid august ... and they should be all set ... in drought its all about getting water down into the root zone .. where the plant needs it.. not sprayed on the surface ...

ken

btw..there is a shrub forum ... just fyi

i just happened to look out my window.. and my kwazan cherry tree has lost about a third of its leaves since the storm a few days ago..

just reinforcing my comment its been a rough year ..

ken

'Green Velvet' is moderately susceptible. Not as bad as some varieties but certainly not resistant.

my guess is leaf miners and psyllid infestation..an extension office diagnosed my samples with these diseases..mine looked like yours..

treatable but I removed mine..

Perhaps. But I’m looking at the circular and oval patches, consistent with a fungus, and dry brown dead foliage. I don’t see any miner tunnels.

floral..when I took my samples in a guy tore off a leaf..there was a "bubble" (my term) on the underside..ripped it open and there was a "worm" (my term) in it..I never knew such a thing existed..

now that you mention it I don't recall tunnels on mine..

I received an email from the extension office listing those conditions with treatment recommendations..

Yes, I know what leaf miner damage looks like. Not always tunnels. They leave empty blotches with the top and bottom leaf surfaces intact. But I don’t see anything like that in the photos.

a screenshot..mine looked like this..

I read that blight has black stems..mine were damaged but didn't have blight according to the extension office..