above ground potatoes?

[svalli]

I have some "feral" potatoes growing in the garden in area were I did not plant anything this year and was growing potatoes year ago. Today I noticed a wilting potato branch sticking out from the garden fence and some purple berries on it. I picked up the branch to take a closer look and those are not berries, they are like small tubers with leaves growing from them. There are some still green potato plants on the other side of the fence, but none of them have these small tubers on branches. Has anyone seen this before? I wonder if these tubers would root, if I planted them. Too bad it is getting cold soon so, I can not experiment with them.

[Tom Wagner]

Every year during the last 6 decades, I have seen this on certain potato varieties. I always thought it was a weakness of sorts within the variety. I will explain the more scientific natures of it later in this message.

I have planted these aerial potato tubers with some success, but it is not something I recommend. It is fun to see the various colored fleshed types expressed in these aerial tubers. Sorry, I have no pictures.



If stolons and underground stems are severely infected, most noticeable are the signs of Rhizoctonia, the flow of starch from the leaves to the developing tubers is interrupted. This results in small, green tubers, called aerial tubers forming on the stem above the soil, or more exact, leaf axils on aerial stems Formation of aerial tubers may indicate that the plant has no tubers of marketable quality below ground.

Factors that could cause this:
·insect and mechanical injury to lower parts of plant stems,
·various pathogens such as Rhizoctonia solani, viruses and chemical injury.

[svalli]

Originally Posted by Tom Wagner

Factors that could cause this:
·insect and mechanical injury to lower parts of plant stems,
·various pathogens such as Rhizoctonia solani, viruses and chemical injury.

This branch was bent and half way broken where it came through the wire fencing, so the tubers must have been caused by the mechanical injury. I should go dig the area to see what kind of tubers I can find under ground.

[FlipTX]

Please post an update when you can! I'm curious to find out if you discovered anything underground.

[svalli]

I dug them up on Tuesday and found few 2" long and a lot of tiny purple potatoes. By the shape I determined that the variety is Peruvian Purple, because they were slimmer than the All Blue, which was the other one of the purples grown on 2006.

One of the stems must have got damaged and that is why it grew the tubers above ground. Other stems, which grew from same location did not have these tiny tubers on them.

I did also find two other spots in the garden, where I did not plant anything and had potatoes growing in middle of weeds. I dug up the soil and found more Peruvian Purple potatoes. Color of these potatoes make them hard to find, so I must have left many of them in ground year ago. For some reason these potatoes looked more even in shape compared to the ones I had year ago. We had more rain this summer and I did not fertilize the area at all. I wish I had planted potatoes this spring, since it seems to have been a good summer for them.