I had the same problem and tried everything... Indelible markers, permanent markers, etc. They all faded. I think it's something to do with the UV rays from the sun that causes them to fade.

I now use pencils to write on the labels. It seems to last for years, and the added advantage is that you can rub it out and re-use the plastic sticks. I just rub a damp bit of soil over them, rinse them, and they are as good as new. The only problem with re-using the plastic sticks is that they tend to break up and disintegrate after a few years, probably caused by the same problem... UV light breaking down the plastic.

pencil

Staedtler Lumocolour permanent black, fine point. Lasts better than pencil for me. This question crops up regularly and the replies are always varied, with most favouring pencil. Run a comparison and let us know the results!

Yup pencil!

I don't agree with you Steragram. Just kidding, I read your answer on the other post with the same question, haha.

Horses for courses Myron - I struggle to read the pencil after a year or so. :))

I've found that sticks that have been re-used seem to work better as the surface is rougher. If you rub a bit of damp soil on the sticks and clean them off before writing on them, this roughens them a bit and the pencil lead will be legible for longer. Also, it depends on the hardness of the pencil.

Amazing what we learn through experience isn't it? come to think about it I've found the same thing re dirty labels.