This is how your tattie plants should look, isn't it? And you don't require a degree in horticulture to grow them, do you?
Well, in 2008 our potatoes looked like this!
Weird! The only difference that year was the introduction of some manure from a local farm. I had some hazy recollection of hearing about vegetable growers and allotment holders that had problems with manure in previous years.
I discovered that the manure had probably been contaminated with aminopyralid. This is a herbicide used on grass crops which are then used as a feed particularly for horses. It seems to go through them and the manure is infected. Nobody knows how long it stays active for but I was given varying time scales from a few months to several years by different experts.
What could we do about the problem?
We considered taking out the contaminated soil and replacing it. But that would be expensive and the old soil would have to go somewhere. We could add charcoal which is said to help break the herbicide down.
We decided to carry on the 4 year crop rotation and leapfrog that area when we got to it. It had also been suggested by the experts at the Botanic Gardens in Edinburgh that we try planting one or two potatoes in the infected area to see if they showed signs of stunted growth.
Most importantly we have learned to ask were our manure comes from(it's a third degree for these poor people with horses) and what herbicides are used by the farmers. I tend to only use
our own home-made compost and green manure crops and avoid untraceable manures.
So far we haven't had any further problems.
This year for the record, we planted Rocket. Kestrel. Desiree and Pink Fir Apple.