I have discovered I have four potato plants in my rather small garden
that have grown from potatoes in the compost - we only have two small
beds and put almost a whole dalek full of compost on the two earlier
in the year, clearly some of it wasn't rotted.

I have done nothing with them, but am wondering a) is there any point
in doing anything b) if so, what (I seem to have a vague idea about
shoring them up or something like that!) and c) if I am likely to get
any potatoes from them and if so, how will I know they are ready?

Thanks from a novice gardener with many daft questions

Katie