Growing container potatoes

My container potatoes are full with compost and the foliage is about foot high should I wait untill they flower before I harvest them.

 

I would

 

note that not all potatoes flower ... weeks-from-sowing is a good indicator, depending on the type of Potato. Other than that have a "feel" and see how big they are, this is usually easier in a container than in the open ground.

 

What I've done in the past is, as Kristen says, have a 'feel' around and, if there are some which I think are ready for eating, I ease them out, hot foot it into the kitchen with them and leave the rest to grow on.