"Moonraker" wrote

Normally I have no problem with leeks, this year is an exception. They have
grown normally, however when I came to use the first, yesterday , on
cutting them there are rust colour thin "trails" along the leeks. These
persist most of the way through them. Any ideas as to what the problem
might be and how I can avoid it in the future please?

I'm afraid to say that sounds like Leek Moth. Did you notice if the leaves
of your leeks looked like they had been at war this year, a bit ragged at
the tips to say the least? You may also notice small net like cocoons on the
leaves.
If it's Leek Moth there is nothing you can do and you will get it every year
from now as it's now got to your area. We have had it for years and find the
plants seem to grow through the infestation, especially if they are planted
a bit later than normal.
I've also had them attack onions at the neck. :-(
--
Regards Bob Hobden
Posting to this Newsgroup from the W. of London UK