Most people work hard at growing lawns, taking good care of them, and keeping them green but occasionally you may want to kill grass permanently. For instance: when planning a deck or patio, cleaning cracks in concrete, along the edges of sidewalks and pathways, around fence posts, etc.
As gardeners try to eliminate or reduce their use of chemical herbicides, they have tried all types of solutions. One option is spraying grass with vinegar. But does household vinegar really work? Here is what you need to know.
Does Vinegar Kill Grass?
Applying 5% vinegar to established grass usually kills the blades. It is especially effective on broad-leafed types of grass and plants. One application of vinegar does not kill grass roots. The plant just grows new grass blades. Vinegar does kill new seeds that are less than two weeks old but it does not kill seeds that have not sprouted.
How Vinegar Works On Grass
Vinegar applied to grass blades ruptures the cell membranes allowing fluid to escape. The fluid evaporates–dehydrating the grass stems. The grass blades die without fluid and moisture.
Vinegar is not drawn into the plant through the leaves–leaving roots untouched and alive. Vinegar running down the grass blades becomes inert when it touches the soil. It makes no impact on the root structure. New grass starts growing immediately after the vinegar is applied.
Grass prefers soil pH from 6.0 – 7.0. Slightly acidic to neutral. Repeated use of vinegar makes soil more acidic which weakens grass roots. They become more susceptible to diseases, stress, and pests–all of which can kill the plant.
Repeated applications of vinegar to kill grass is a long process and may not be effective on healthy well-established plants. You also run the risk of splashing vinegar on other plants and killing them–especially broad-leafed or flowering species.
Things To Know If You Use Vinegar To Kill Grass
Vinegar may kill grass over time–with regular applications. It usually does not kill grass permanently. Keep these things in mind if you decide to use vinegar to kill grass or weeds.
- Concentration – Applying higher concentrations of acetic acid (vinegar) increases the success rate. It also can do more harm to the soil and surrounding plants. Many vinegar-based herbicides are registered with the EPA. They contain 20% – 30% horticultural vinegar by volume and are very effective at killing grass and weeds.
- Application – Spraying vinegar directly onto the grass blades is more effective than pouring it on the ground.
- Timing – Spray during vigorous growing seasons–not when the grass is dormant.
- Grass Type – Vinegar works best on broad-bladed varieties of grass.
Soil Type. Vinegar is more effective on acidic soils. Using too much vinegar for too long can make soil too acidic for some plants.
Household vinegar containing 5% acetic acid is not powerful enough to kill grass. It is not registered as a herbicide with the EPA and is therefore illegal to use as a herbicide. Stronger vinegar-based herbicides often require professional application.
