Allotments 4 All

there are potatoes coming through from the previous plot holder, probably several years old as the plot has been unused, will they be ok to let grow and eat the pots?

Personally I wouldn't as they will harbour blight...  :-\

I aggree and would keep a very close eye on them any signs then of with their heads and burn the evidence.

phew, thanks for that! They are in an empty bed at the mo' so I'll have a good dig about in it today! :-\

We get blight every year on my site, and I suspect the reason may be old neglected spuds. Get them out and be on the safe side!

It is most unlikely indeed that volunteer potato plants will harbour blight for two reasons.  The first is that a blighted tuber left in the ground from last years crop will, by spring, be too badly rotted to produce viable topgrowth.  The second is that potato blight does not originate in the tuber and work upwards, but in the foliage and stems whence it works downwards.  I invariably get a number of volunteers coming up among my peas and beans (which follow my potatoes) and because trying to dig them out would cause too much damage I always leave them in.  When blight appears they are always the last plants to catch it - presumably because they are isolated solitary specimens surrounded by a different species rather than grouped in a bed with other solanums.

The old potatoes which Robert suspects of perpetuating blight are not the ones growing as volunteers, but the ones which the scruffy gardeners reject and simply throw under the nearest hedge, ready to broadcast the spores freely come the Smith periods

Interesting conflicting opinions! Anyone else?! I went down yesterday and there are potato plants coming up all over the place now! I dug some out and some were growing from very old rotten looking pots and some were growing from the tiniest little potato ever - like the size of a broad bean!

So why do the spuds thrown under the hedges, which are vulnerable to frost in addition to blight, survive and spread it preferentially? I can understand some of them surviving in a situation where a farmer leaves a pile of rejects, with the ones at the bottom protected from frost, but the survivors would effectively be in the same position as a leftover potato coming up on an allotment.

I don't dig them out if it would damage another crop, but I do keep pulling them.

I quite agree that the main reservoirs of blight every year are the piles of rotting spuds simply left out by the commercial growers.  I was merely pointing out why your suspicions that the volunteers are also responsible are groundless.  But there are two reasons why the possibility exists with the ones thrown under the hedge.  Firstly a reasonable hedge in fact provides quite considerable frost protection, particularly if the normal leaf fall is allowed to remain and provide a covering blanket on the ground beneath.  Secondly, until this last winter, the winters for several years have been increasingly mild and insufficiently cold to kill off many fungal and viral diseases in partly protected places.  I`m afraid that I use my very smallest (thumbnail sized) spuds as squirrel amunition in my catapult and I frequently find these sprouting happily in sheltered places the following spring.