Another sickly plant.....

I posted about my sickly Skimmias the other day and now I'm posting about my sickly Camelia - another ericaceous loving plant.
Unlike the skimmias that were potted wrong and in unsuitable soil this Camelia is in a large enough pot, in ericaceous compost and has been fed according to instructions as often as required, I'm pretty sure this can't be Chlorosis.
And yet it still looks like this

Despite obviously ailing from something the Camelia is covered with healthy buds as usual

 

Anyone have any idea of what it suffers from? I'd really love to know.
All I can think of from a little internet searching is that maybe it's getting too much sunlight. I keep it in the polytunnel as it would not survive up here outside and it isn't shaded in any way. I wouldn't have thought that would be an issue but apparantly Camelias do not like early morning sun - who knew!
But would excess sunlight cause this? Could those brown splodges be burns?
I've quickly moved it to a slightly more shaded area of the polytunnel to avoid too much sunlight but  I'm not even sure if this is what ails it. HELP!! I love my Camelia and would hate to lose it cos it produces flowers like this

On a brighter note, guess who managed to get out in the garden today? Go on guess.....
Yup, yup, yup the snow (what there was of it) has gone, the winds have dropped to barely noticeable and this means the temperatures are not quite so cold as they have been.
So myself and Mr TG (rare day off from work, well his usual work anyway) spent the day outside - I was clearing ugly borders ready for moving around of perennials and a serious mulching and Mr TG was rotovating and everything else associated with being stubborn enough (and foolish enough?) to believe he can turn all the land over with just his trusty rototiller.

He's actually done alot more than is shown here but I wasn't nearby to catch a picture of him rotovating (I'll snag him tomorrow though) so a raking picture will have to suffice for now.
He's determined to do this himself (maybe to prove his COPD does not affect him one iota -insert rolling eyes here) and luckily we're not bothered about a perfect field. we just want to get it levelled enough to mow it (it's full of digger tracks and Dane holes and a danger to walk on at the mo).