Raised bed site

Asked May 10, 2017, 7:02 AM EDT

I would like to put a raised bed on a spot that was treated with ortho Groundclear a year ago. I would like to avoid the time and expense of a soil test if it is safe. Could you please advise. Thank you

Chester County Pennsylvania master gardener program raised bed gardening horticulture

1 Response

Here is a link to the product information on Ortho Groundclear published by the US EPA. The major active ingredient is glyphosate which is the same active ingredient in Roundup. It also has a chemical that suppresses weeds for a year in normal conditions. That means it persists in the soil, but is eventually broken down.
I would raise the bed a foot and line the bottom with some wet cardboard before adding the new soil. Cornell University suggests 60% topsoil, 30% compost, 10% perlite. That mix can vary with the clay content of your topsoil. After you plant the bed with young seedlings and if you will see signs that the seedlings are not growing properly, I would have the soil tested. I had an experience where some kind of residual herbicide came in with some compost I bought from a landscape supplier. The seedlings I transplanted soon had white areas and dead areas on the leaves and were stunted. They are still alive, but have never grown.