How do I kill weeds without harming grass?
Written by
Nguyen Minh
Reviewed by
Prof. Martin Thorne, Ph.D.To kill weeds and not grass, you need precision with your chosen method. A general application might harm your lawn, but a targeted treatment won't affect the desirable turf. A good way to kill dandelions without harming my blue grass is to make 2 or 3 passes with a vinegar brush. You keep your lawn green by isolating weeds in areas surrounded by grass.
Liquid Solutions
- Use foam brushes for vinegar application directly on weed leaves
- Employ shield tools when spraying near grass borders
- Spot-treat at dawn when dew protects grass blades
Physical Barriers
- Install cardboard collars around weeds before salt treatment
- Create soil berms to contain boiling water in pavement cracks
- Use cookie cutters as metal guides for precise pouring
Keep a buffer zone of 8 to12 inches around the edge of your lawn whenever you do these treatments. Use garden flags to mark the areas beforehand. I use bamboo stakes to mark the 'safe zones' nearer my fescue lawn. You prevent any potential drift from landing on the grass by having some sweet boundaries to comply with. Replant any bare patches with grass seed after you are done.
Choose corn gluten meal for whole-lawn protection, eliminating the need for spot treatments. Apply 5 kg per 100 sq ft in early spring to avoid weed germination. This organic pre-emergent fertilizes your grass while stopping invaders, and I add it to my overseeding mix for thicker turf. You stop weeds while nourishing your lawn.
Manual, or as one friend calls it, "traditional", removal is most effective on weeds near the grass crowns. Dig them out with Ice-pick-seizing trowels when the soil has softened after rain. Sever the tap root a couple of inches below the surface to discourage re-growth. I used to keep a weed-killing knife in my apron pocket. You dispose of weeds in a chemical-free way when doing so in easily injured areas.
Raise mowing height to 3-4 inches (7.6-10.2 cm) to shade out weed seedlings. Taller grass keeps sunlight away from weeds trying to germinate. I mow weekly at the height of the season with brush-cutting mower blades, and you create a natural suppression with proper lawn care. Also, try deep but infrequent watering to strengthen the grass roots.
Read the full article: 10 Natural Weed Killers That Work
