Kitchen Garden Forum

Quite a few of our potatoes are turning out to have hollow hearts, outwardly unfamaged but a hole in the middle, therefore making them useless for baked potatoes. Varieties include Sarpo Axona, Sarpo Mira, Verity and British Queen. Is this year's weather to blame - a long dry spell followed by heavy rain?
Monika

Monika wrote:Quite a few of our potatoes are turning out to have hollow hearts, outwardly unfamaged but a hole in the middle, therefore making them useless for baked potatoes. Varieties include Sarpo Axona, Sarpo Mira, Verity and British Queen. Is this year's weather to blame - a long dry spell followed by heavy rain?
Monika

Hi Monika,

I have no idea if I am right or not but I have always been led to believe that when a potato hearts, it is down to the watering conditions and a rapid growth spurt, so I would be interested to know also.

I think I read somewhere that the Sarpos,although the plant tops stay healthy and growing if left to long the potatoes can go hollow,I know ours were still flowering when we lifted them 3 weeks ago.I don`t know about other varieties tho`.

I've looked it up inAlan Romans book. I got it too with Sarpo Mira and Sarpo Axona.It's a physiological disorder caused by insufficient calcium and is called Hollow Heart and is more prone in a large potato like the Sarpos.

If the reason is lack of calcium, how do we introduce calcium? We obviously can't use lime on the potatoes (the pH is just right, in any case).

Hello Monika
I had a problem with internal rust on some of my potatoes last year and the cause in my books was given as a lack of calcium. What I did this year was to sprinkle a little lime along the row just before I earthed up and it seems to have done the trick. I thought it might encourage scab but my impression is that it is no worse than I normally get. I think that this lack of calcium business is simply a lack of availability - there is sufficient calcium is present in the soil but the plants are unable to take it up fast enough when they are growing rapidlly.
Another way round the problem might be to use the method that's recommended for dealing with brown pit in apples - use a solution of calcium nitrate as a foliar feed. For apples you need to spray but for potatoes I guess that all you will have to do is water the solution over the leaves - add a bit of wetting agent such as washing-up liquid to the solution so that it just doesn't run off the leaves. Do it at the marbling stage when the tiny tubers are beginning to form. One source of calcium nitrate is Chempak's 'Calcium multi-action' which is widely available. Not sure what strength you might use but I don't suppose its that critical. Do one plant as a test first then the rest a few days later if all is well.

John

Hello John, I'll try that next year!