Gardening_Convert wrote:
I have some 'Rocket' potatoes growing in a large tub. The shoots are
showing over the top of the compost now . When should I earth them up
and by how much should I earth them up ?

I start to earth up when the plant is about 15/20cm (the length of my
thumb to my little finger). Sometimes I put mulch on it, grass
clippings etc. Hope there's room in your tub!