Safe to plant after pesticide application
I want to plant a small garden in my Mother's yard this Spring. She had a lawn company spray pesticides last year. Is it now safe to plant a garden? I do not know what type of pesticide, herbicide they sprayed, but I believe they are regulated. Sincerely, Cheryl K.
Timing will depend on what you want to plant, but probably not for reasons of residual pesticides given how long ago they were used. The lawn company should have provided information on what was being sprayed, and for what purpose. Knowing this would help determine when (or if) such problems can be expected to re-appear. Herbicides may impact new plantings if used recently enough; this also depends greatly on what ingredients were used and for which weeds. Pre-emergent herbicides are used to prevent seed germination on the soil surface; post-emergent herbicides are meant to either kill all existing top growth or be absorbed to kill the roots. Many break down when in contact with soil for a length of time.
Since it's likely they were used no later than autumn of last year, we suspect there will be no issues with planting this spring. Are you planting edible plants or ornemantals (decorative flowers or evergreens)?