Apostrophe Question

One for the pedants out there (you know who you are) because for once I’m just not sure…

In Homebase over the weekend, I ended up looking at seed potato sets. I know, what a classy life. Anyway, reading the back (Hey, I was bored) I saw this…

Apostrophe in the text of the seed potato set

Is this apostrophe errant or not?

I know that an apostrophe is used in the case of compressions (i.e. “there is” becoming “there’s”) but I’m fairly sure it doesn’t apply in the case of an abbreviation.

So to my knowledge this apostrophe is incorrect, but equally I’ve been known to be wrong on these finer points…

So – am I right? Or is this OK?