Are these potatoes?

Yet another daft newbie question from me.

I was wondering if what I'm seeing here actually is potatoes. I planted neat rows, but some of these little plants are growing in between the rows and some are growing in my onion patch (the previous plot owner did grow potatoes in that plot though). Also one's growing in the bottom plot which I didn't think had anything growing in it.

Here's a pic of the one growing mid row (sorry for quality) and one growing on the bottom plot:



Here's the ones growing in the onion plots:



And here's a montage of various pics of what I hope are potatoes, the bottom right one turned out to be another one growing in the onion plot after closer inspection:



If they are potatoes do I start earthing up now or do I wait a bit?

Thanks a lot for any help.

The ones that you didn't plant, (volunteers), really need to come out if you can, as being live plant material, they can harbour blight over winter.

If there's no frost predicted in your area I'd let them grow a bit bigger before earthing up - I'd recommend letting them grow to about about 6 inches tall.

Thanks to everyone for their help here. Got a question about this though:

The ones that you didn't plant, (volunteers), really need to come out if you can, as being live plant material, they can harbour blight over winter.

The ones on the onion plots I don't think I can remove without damaging the onions and the one growing on its own on an empty plot doesn't seem to be doing any harm - can't I just leave it and see what happens?

I would be far more concerned about these volunteers destroying the rotation and harbouring globidera rostochiensis or g called species of PCN than e.g. blight.
We rotate crops to destroy the green bridge between crops. Having weeds (which volunteers are) such as this will increse pest pressure.

I would be far more concerned about these volunteers destroying the rotation and harbouring globidera rostochiensis or g called species of PCN than e.g. blight.
We rotate crops to destroy the green bridge between crops. Having weeds (which volunteers are) such as this will increse pest pressure.

So would you destroy this years onion harvest to do it?

I just hoe the tops off and have never had eel worm  (potato cyst nematodes) as Mark-S seems worried about

DDs mention of blight is a good reminder to destroy these stray potatoes. Equally any that are sprouting from compost or waste heaps, where they were perhaps dumped because they were diseased, should be sought out and destroyed.

Look around your allotment site and try and get everyone to do the same, or quietly do it anyway.

Although blight is blown on the wind there is no point at all in leaving a potential source of infection on your own doorstep.

I have recently purchased one of the new Roundup Gel dispensers. A bit like a deoderent dispenser, one click and more gel is oozed out. Far better than the old brushes and ideal for putting Roundup into tight places. A little expensive at £8 but we will have to wait and see how long it lasts.