repairing herbicide use in garden

Asked May 25, 2014, 11:57 PM EDT

hi, having used some round up over the years (last fall to kill grass at edges and paths! in my vegie garden...)...and bought in leaves from city gardens to my garden,,,how do i repair that damage/toxic load when i did not make such smart choices...does roundup carry over in t the soil?...hearing much lately, i am not going to use again....will plants that volunteered in some paths be edible do i repair/heal the soil so it is good for me and plants, etc. to an organic garden. thank you. sylvia

Stevens County Washington

1 Response

Hi Sylvia-

The research has shown that the active ingredient in RoundUp (glyphosate) can remain in the soil for as many as 130 days after application, though averaging between 40 and 60 days depending on soil type , application amount, etc. However, glyphosate is tightly bound to the soil and would likely not affect your plants, even if it was physically present in your soil. There are no studies showing human toxicity from glyphosate at label recommended concentrations. And, given that glyphosate is not known to build up in the soil for more than 40-60 days, on average, I suggest that your volunteers are safe to eat (speaking strictly in regards to RoundUp sprayed last fall). If your concern is only RoundUp, I do not think there is reason to worry about your soil.

Organic production is another story. You can use organic practices, but in the current system "organic" production is subject to annual certification and is not practical for the home gardener. That certification is regulated by the USDA's National Organic Program, and requires that no prohibited substances be applied to the soil for 3 years prior to certification. There are chemicals that remain in the soil that long, and longer; however, glyphosate is not one of them.