[Charles Kirsfelds]

Just started harvesting a few of my charollette potatoes from the allotment.

As the tubers come out of the ground they look absolutely fine with hardly a blemish and with the hopes of a good crop this year.

After leaving them for an hour or two so that the skins can dry out, brown rather irregular streaks, patches and other assorted weird shapes appear. 

The haulms of the plants look healthy with no sign of blight or other infection .

The affected areas range from light brown through to a very dark brown and form a depression on the surface of the potato that looks wet compared to the dried skin.

The blemish is easily scraped off, with so far no ill effect to the flesh of the potato.
 
Have noticed  that some of the earlier potatoes harvested with the darker patches have started to develop some fungus within the affected area. 
 
Luckily at the other end of the long raised bed the kestrel potatoes have not been affected

Some pictures attached.

Any clues as to the problem with the charollette potatoes would be most appreciated.

[Aunt Sally]

Could this be physical damage ?

Some varieties of new potatoes are quite tender when first lifted and must be handled gently until the skins set. 

https://potatoes.ahdb.org.uk/media-gallery/detail/13213/3356

[Gardener and Rabbit]

Hi Charles,
 
There's a useful page on the RHS website here:

https://www.rhs.org.uk/advice/profile?pid=471#section-1

They also mention a couple of other rots: violet root rot, and from your pictures those patches look like they may be violet coloured; also, watery wound rot which is caused by harvesting slightly immature tubers in  hot weather, which may tie in with the rapid development of symptoms after lifting that you describe.

G&R

[Charles Kirsfelds]

Thanks for the suggestions and pointers.

Can rule out physical damage as the  soil we on the allotment is quite light and the potatoes where harvested by hand with no need for a fork.
 
At the moment the nearest match maybe violet rot when you compare the potatoes with other pictures on line - however didn't notice anything on the roots during harvesting.

There are still two short rows of charolletes still to harvest, so when the soil dries up after the downpours we have had over the last few days will check if there are any other signs.

Charles