Days of Waiting… Then Regrowth
Vinegar works fast – you’ll see wilting within 24 hours. But here’s what nobody mentions: a few weeks later, those same weeds are back. If you want results that actually last, there’s a smarter approach.
How Long Does Vinegar Take to Kill Weeds?
Vinegar works quickly – you’ll typically see visible damage within 24 hours. The acetic acid burns plant tissue on contact, causing leaves to wilt, turn yellow, and shrivel. In ideal conditions (warm, sunny weather), you might even notice effects within a few hours.
This speed is one of the main reasons vinegar has become such a popular homemade weed killer. Compared to systemic weed killers that can take 2-3 weeks to show full results, the instant gratification of vinegar is appealing.
However, there’s an important distinction between “damage” and “kill.” While vinegar damages weeds fast, it rarely kills them permanently. Understanding this timeline – and what happens after – will help you decide if vinegar is worth trying.
The Vinegar Timeline
0-6 hours: On a warm, sunny day, you may notice the first signs of wilting as the acetic acid begins to dehydrate plant cells. The weeds start to look slightly droopy.
24-48 hours: This is when the visible damage becomes obvious. Leaves turn yellow or brown, edges curl inward, and the plant looks thoroughly scorched. At this point, many gardeners assume success and move on.
3-7 days: The visible parts of the weed appear completely dead. Brown, crispy foliage that looks like the job is done.
2-4 weeks: Here’s where the disappointment sets in. Fresh green shoots begin emerging from the base of the “dead” weeds. The roots survived, and the plant is regenerating.
This regrowth cycle is why vinegar isn’t truly effective as a long-term weed killer. You’re essentially trimming weeds with acid rather than eliminating them.
Factors That Affect Speed
Several factors influence how quickly vinegar damages weeds:
Weather conditions: Warm, sunny days produce faster results. The heat accelerates dehydration, and sunlight intensifies the burning effect. Apply on a dry day with no rain forecast for at least 24 hours – rain will dilute and wash away the vinegar before it can work.
Vinegar concentration: Standard household vinegar contains about 5% acetic acid. Horticultural vinegar with 20%+ concentration works faster but is also more hazardous to handle and no more likely to kill roots.
Weed type and size: Small, young weeds with minimal root systems show damage fastest – and are the only ones likely to actually die. Established perennials with deep roots will show surface damage just as quickly, but will always regrow.
Application method: Thorough coverage matters. The vinegar needs to contact all the foliage to cause maximum damage. Use a spray bottle to coat leaves completely, or pour directly into paving cracks for concentrated application.
Why Speed Doesn’t Equal Effectiveness
Here’s the crucial point many vinegar advocates miss: fast visible results don’t mean the weed is actually dead. Vinegar is a contact herbicide – it only damages what it directly touches. The root system, safely underground, remains completely unaffected.
Compare this to a strong systemic weed killer. Yes, it takes 2-3 weeks to show full results. But during that time, the active ingredient is being absorbed and transported throughout the entire plant – leaves, stems, and crucially, roots. When it finally works, the weed dies completely with no chance of regrowth.
With vinegar, you get fast cosmetic results followed by regrowth and repeat treatments. With a proper weed killer, you get slower initial results followed by permanent elimination. For tough weeds like brambles, ivy, or nettles, there’s really no comparison.
When Vinegar’s Speed Is Useful
Vinegar’s quick action does have some legitimate uses. If you need weeds to look dead quickly – perhaps before a garden party or house viewing – vinegar will deliver that cosmetic result within a day. Just understand that it’s temporary.
For very young seedlings that have just germinated in patio cracks or block paving, vinegar may actually kill them outright if you catch them before they develop substantial roots. Combined with regular maintenance, this can help keep hard surfaces relatively weed-free.
But for established weeds, or anywhere you want long-term results, speed of initial damage is the wrong metric to optimise for. What matters is whether the weed stays dead – and on that measure, vinegar consistently fails.
Alternatives Worth Considering
Other DIY methods like salt, bleach, and boiling water share the same limitation – they’re all contact killers that leave roots intact. If you want something that actually works long-term, a long-lasting weed killer containing glyphosate is your best option for driveways, paths, and gravel areas.
For more on vinegar’s limitations and how it compares to other methods, see our complete guide: Does Vinegar Kill Weeds?
Stop Watching and Waiting
One application that kills roots completely. No regrowth, no repeat treatments, no disappointment two weeks later.
