Potato Rot
Stonefree
Posts: 13
Hi, I've planted two rows of Lady Christl earlies and while most plants are growing well, 6 out of the 24 aren't. I've dug the 6 up today and found that the seed potatoes are rotting. They seemed healthy when they went in, onto well rotted manure in a 6" trench. Last year there were brassicas in this spot, but there might have been potatoes here the previous year, before we took on the plot. The leaves of the affected plants are small and slightly darker green than the healthy ones, but there is no sign of blight. The healthy ones seem completely unaffected, and there is no pattern to the placement of the rotting ones, they aren't adjacent, etc. Any help gratefully received. (In the pic, the light brown mass roughly in the middle is a rotting potato.)
Posts
Today I had to remove another 6 which weren't growing as well as the others, and they were all completely rotten, smelling bad, and with the lower stems rotting to black. A quick google came up with Potato Blackleg/Soft Rot, a bacterial infection which was most likely present on the potatoes when they arrived. Apparently it can over winter but we didn't have potatoes in this spot last year.
So that's half the Lady Christl gone. I'm hoping that the rest will be OK, the difference between the healthy ones and the infected ones is marked. I also have a row of Sarpo Mira in between the two rows of earlies so I'm hoping the infection doesn't spread to them. There is no treatment for the bacteria, apparently.