Q.What is the best solution to herbicide pollution in raised bed soil? The source of the contamination was either the potting soil
or the peat pots used for seedlings. The pollutant is probably an aminopyralid herbicide applied to hay that somehow was incorporated into the manure or other organic material used in the potting soil or the the formulation of the peat pots. Plants affected include tomatoes, sunflowers, and zinnias. The damage has been devastating.
Certified GKH Gardening Expert
Here are some tips for improving soil after contamination. If it's not cost prohibitive, I think I would replace the soil in the raised bed and start over with the plants.