Buddleia leaves being eaten

Zen Dog

Here to pick your brains again! Two of my young buddleia are having their leaves chomped by some seemingly invisible pest. I've scoured the leaves and the only possible culprit I've seen are two really tiny weevils. I'd suspect the dreaded vine weevil but everything I've read says they eat the edges of leaves and these are being eaten from the "middle" first. The flowering doesn't seem to be affected but I'm a bit worried about whatever the culprit is moving into something less robust.  A nearby part of the garden is planted with loads of heucheras which I treat with nematodes in the hope of keeping them healthy and would be more than a little upset if they were destroyed. I have been chemical free for a while now and am learning to deal with some plants being rather scraggy looking, as long as I know they'll recover. I'm hoping your collective brains will solve the mystery!......tried to post photos but failed. Files not large so don't know why. Basically damage starts as small holes in middle of leaf and ends looking like very fine lace. 

Lyn

It’s  probably little caterpillars, but then that’s why you grew the buddleia in the first place. To attracted butterflies.
I don’t think it will hurt it, after it’s flowered you cut it down by half then next Spring, cut right down. You’ll get new growth then if you can stand looking at it chewed for now. 

Zen Dog

Whatever they are they must be tiny because other than the two tiny weevils there's no sign of anything. I certainly don't mind a few caterpillars though I admit I grow for bees more than butterflies. I've sacrificed a few plants to the bugs this year and have been repaid in ladybirds mainly. Very exciting watching the larvae appear. I tend to keep the buddleia quite large as I'm growing 5 as a hedge. The older, much larger ones haven't been affected so far, I suppose the youngsters are juicier! I will cut the two biggest back a bit as you advise as they are monsters this year. Wonderful to see in full flower with all the flying things enjoying them. Thank you for the reply

Lyn

They’re very tough plants, they seem to survive anything,  they’ll grow in nothing, I’ve got them on dry stone walls, no soil hardly.  It will probably flower ok, just have to live with chewed leaves I suppose.