On the face of it, it sounds like your spearmint may have succumbed to
drought and has developed mildew (white powdery coating).

Cutting it back will certainly help, but it would be a good idea to soak the
rootball to flesh out the roots. When recovered (I'm sure it will), it
would be a good idea to take cuttings so that you have a vigorous
replacement for next year.

I don't know what the 'insects' are .. could they be young Crab Spiders
(family Thomisidae)? Spiders would certainly not harm your plant, and
should be encouraged. I'll try and find out if there is a specific pest
of the mints. In the meantime, simply rinse them off the plant with water.
I would be very worried about using an insecticide on your 'working' mint;
it's hard to imagine how you could avoid ingesting it.

Spider
Angel Child wrote in message
...
Hello everyone,

Been lurking for a while )

I have a problem and I'm hoping someone on here may be able to help.

Went away for a couple of weeks and on my return found my Spearmint
looking
very sorry for itself. It "was" about 18inches tall, bushy, in a large
pot
and well used. On my return it had lost most of its leaves (all brown and
dropped off) and the ones that were still attached to the plant had a kind
of white blotchiness to them. I decided the best course of action was to
cut it right back to about an inch and whilst doing that discovered lots
of
little bugs. Very weird looking things. At first i thought they were
beige
coloured spiders but looking more closely they resemble tiny crabs! Ive
tried desperately on the net to find a picture of something that looks
like
these things (no luck). Now i really dont know whether to treat it with a
pesticide (taking into account that i use the leaves quite a lot in
cooking)
or whether just to leave it and see what happens.

Anyone know what these bugs are??????

Angel Child