Does the weed killer I’ve sprayed on my weeds just kill the weeds or is the soil I’ve just sprayed it on now contaminated?
The cosmetic use of pesticides has been banned in Ontario since 2009 although products based on non-synthetic chemicals and considered lower-risk are available. Products for killing weeds fall into two general categories: selective and non-selective products. Non-selective products will kill everything so are generally used to kill weeds and grass on patios and driveways. A selective product will kill only the intended target. For example, products are available to spray on lawns to kill dandelion and other broad-leaved weeds and will not affect the grass itself. As to whether these products contaminate the soil, they will remain active in the soil for a period of time. They will be ingested by soil organisms such as earthworms and may also move through surface runoff to other parts of your garden. Be sure to read carefully the instructions that come with these products for usage and for disposal of containers.