Hydrangea scale - spray with insecticidal soap, but make sure the hydrangea has been well watered first, and don't spray in sunlight.

This Hydrangea scale is a new one to me having seen it come up a few times on here now. Another one now logged in for future!

Must be a lot of it about this year, Fractal - I'm sure the Provado scale treatment would work on it, but Hydrangeas can be a bit funny about insecticides being sprayed on them, what do you think?
Another point to note on this particular form of scale - it can also attack Acer and Prunus.

I'm guessing here but as Provado contains mostly Nicotine or derivatives (Nicotinoids) it should be ok to use. That part I knew.....

....the active ingredient is the Nicotinoid called Imidacloprid. More about it here: http://en.wikipedia.org/wiki/Imidacloprid

Yes, I've read all about imidacloprid, don't fancy using it because its known to upset bee colonies. Re the hydrangea, my RHS book says they are sensitive to pesticides, so they recommend insecticidal soap or malathion, and we all know the last is no longer available.

Hmmm, interesting. The trouble with these little blighters is of course they are wrapped up in waxy material thats difficult to get into with a contact insecticide. You are probably right of course to use insecticidal soap. Maybe a few applications at several times will do it.

Well having looked it up again, the likelihood is the nymphs are already gone from those egg sacs, but they do overwinter on the wood, so probably worth treating anyway.

Thanks I will spray the plant asap