I use a softish pencil! e.g. HB

Plus for your information iuse a piece of steel wool to clean them.

I have never found anything that lasts

Same as Teegee, an ordinary pencil is as good as anything.

I asked the local Council Recycling Team what they used to put the numbers on wheelie bins. They replied they use a 'Sharpie ' pen.
I went to the stationers. They had them. I think thats the right spelling. Just went out in the rain to my car to check, my label box is under a heap of tools - was getting wet, so came back in !

Take a photo of your border and put it in a scrapbook and draw pointers to the plant's, that's what I do, then you have a record of everything:o))

Ladyessex1 what a good idea!! i bought permanent outdoor label markers about a month ago to label all seedlings etc and nearly every label now has nothing on!! so will have to leave everything potted up until i know what they are.

Sharpies don't stay on the labels! All mine have nothing on them either!!

Thats odd. I found the Sharpie Pen on my dashboard !
It has Sharpie Permanent Marker on the side. Where the men have written house numbers on the wheelie bins they are still there months later. Maybe there are several Sharpie products ?

I find everything fades except pencil - and I've tried Sharpies too. I think it may be to do with the sort of surface you write on. I heard that the youngsters who "decorate" road signs with their doodles use Sharpies - and it doesn't seem to fade there.

My Sharpies are all the permanent type - it even came off my wheelie bins - maybe the Scottish rain :))))

Try a Staedler Permanent Lumocolour. Its the best thing I've come across for a long lasting result on plastic, or anything else for that matter. there is one with a fairly fine point.

I bought a box of those on ebay Steragram - and they fade just as fast as the others, I find.

Thank you all for these helpfull answers. I will give them all a try.
Loved the idea of scrapbook, will try this. What a good idea to keep track of where you have put plants as well.

Sorry to hear that Beattie - I wonder if they are exactly the same as mine, which doesn't fade at all.

I wondered if it depends on the plastic you're writing on? I've tried cut up yoghurt pots & marg & ice cream boxes. What do you write on? I've just about given up the labelling fight - even the bought printed labels that come with garden centre plants go brittle and fall to bits after a while.

Plastic normally, including cut up margarine boxes. And when I was a librarian I used that pen for all my book labels simply because they never faded. I wonder if your pen's exactly the same sort as mine - I found they were quite hard to track down. I would tell you everything it says on it but I can't find it today!