Dean, can you tell me what the name of the plant is, please? I can't quite decide its identity. And, are you talking about the crusty spots on the foliage, or the all over white-ish cast of the leaves? The image isn't very helpful.

We also need to know your general location.

what do you mean .... NEW???? ... if really new.. what does the seller or installer say????

they almost look sun burned.. but what rhiz said ...

any indication of any sucking bugs on the reverse ????

ken

Does that whitish powdery stuff wipe off the leaves fairly easily?
If so it may be Powdery Mildew, a common and fairly easily controlled problem with mnay plants.

http://www.organicgardening.com/learn-and-grow/powdery-mildew

kimmq is kimmsr

They are Acmena Smithii, Im located in Brisbane, Australia. The powder doent wipe off, there are no indication of any bugs on the underside. We have had quite a hot summer and even leading in to Autumn, so if this is what sun burnt plants look like, then there is a very good chance thats what it is.

By 'new' i mean they have only been in for a few months, I put them in at around the middle of spring as seedlings.