I think it is more likely that they dried out in summer than blight - but I've had a two week sabbatical so perhaps someone is suggesting blight. Have to say I've never seen on box!

They tend to go brownish as a protection against cold, excessive sunshine or lack of food or lack of water. Grown in pots they use up all the root space and need either repotting or more fertrilizer. Leave them for a month or so and then repot or give a feed. If it is blight they will be thin and brown. If just protection against water loss they will be well filled leaves even if brown.

Thank you both.....that is very reassuring! They are both full of leaves but I suspect may be pot-bound and somewhat neglected re feed etc.There are only a few brittle leaves on them.

Cheers!