non-toxic weed killer
My lawn is full of weeds and is close to the Severn river. How can I kill the weeds in a non-toxic way?
Anne Arundel County Maryland
The first step would be to identify the weeds you have -- annuals or perennials, grassy or broadleaf? There are photos of the most common lawn weeds on our website (https://extension.umd.edu/hgic/topics/lawn-weed-id-and-management) or you can send us photos so we can identify what you have. Different weeds require different management strategies.
There are some types of organic/biorational herbicides labeled for lawn weeds with active ingredients like botanical oils, soaps, iron HEDTA (a selective herbicide but can temporarily darken grass blades), or acetic acid. They are non-selective (meaning they will also kill the grass) and are used to spot-treat problem plants. Research has shown these products are less effective than chemical herbicides and typically need to be applied more frequently. Organic products kill or weaken the green part of the plant, but perennial weeds with taproots, rhizomes, tubers, or bulbs such as creeping Charlie, bermudagrass, and nutsedge will keep returning. If you try any of these products, you will have to read the product label to determine restrictions on use near water.
Refer to our website for information on organic lawn care and tips for weed prevention.