Sickly Potato Plants Emerging

Question

My potato plants took a long time to emerge and what has come up is stunted, gnarly with very few small deformed leaves. I do have a few potatoes planted in a different location and they are normal. The garden area of concern had potatoes planted there the past few years (I did not rotate). The area is below one of my horse pens and has had drainage of manure. This year we added manure from my manure pile. Some of that manure may have been collected from horses grazing on pasture that had been sprayed with grazon (weed control) but had composted for 4 or more years. I am also having my young tomato plants wilting and dying. They were not in the garden they were in my greenhouse. I repurchased plants and several new plants are showing sign of wilt, particularly one cherry tomato planed into potting foil and away from the other tomatoes I am very concerned but don’t know where to turn for possible answers

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Answer 1

Your soil may be toxic. Were the greenhouse vegetables also fertilized with the composted horse manure? The area with horse manure drainage may be suffering from fresh manure issues.

https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/using-fresh-manure-in-gardens.htm

Here's an article that I hope will help. In the meantime, I would suggest you not use that soil for anything for a couple seasons. I'd also contact your local university extension agency for advice on how/whether to use this soil for edibles, and when.
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/contaminated-soil-treatment.htm