WD-40 is not a good choice for killing horsetail weeds. WD-40 is a petroleum-based product that may damage above-ground horsetail growth, but it will not infiltrate the plant’s system and kill the massive horsetail root network. Spraying horsetail plants with WD-40 may poison small areas of the ground, preventing future plant growth for a very long time. It’s best to use a systemic weed killer that destroys the entire horsetail root network and does not poison the soil long-term.
Why You Should Never Use WD-40 to Kill Horsetail Weed
WD-40 is a bad choice as a horsetail weed killer. Unlike systemic herbicides, WD-40 will not be absorbed into horsetail weed and kill it down to the root. Each horsetail plant can create a root network 20 feet (6 meters) in diameter. Using WD-40 to damage the aboveground portion of the plant only offers a short-term fix. The horsetail will soon sprout in a different area.
- WD-40 will not kill horsetail down to the root, unlike specially designed herbicides.
- A horsetail plant sprayed with WD-40 may die back but its large root network will send up new sprouts.
- If you saturate the soil with WD-40 it may prevent any plant from growing there.
- True weed killers will eliminate horsetail down to the root but won’t poison the soil.
Another drawback of WD-40 is that if it is sprayed heavily on the soil, it can poison the ground. The petroleum products in WD-40 can linger and prevent grass and plant growth in that area for years. In contrast, specialized weed killers are designed to kill weeds to the root quickly and then break down to allow desirable plants to grow there.
What Weed Killer Kills Horsetail Permanently?
Crossbow is one of the best horsetail weed killers available. If you’re wondering if Crossbow kills horsetail, the answer is a resounding yes. Crossbow is formulated with 2 systemic herbicides that infiltrate horsetail through the leaves and destroy its entire root system.
- Crossbow is the best weed killer for eliminating horsetail weeds.
- Unlike WD-40, Crossbow kills horsetail to the root.
- Crossbow can be sprayed directly onto healthy horsetail to kill it. Using WD-40 requires crushing horsetail leaves by hand before spraying.
- Crossbow won’t harm grass and won’t poison topsoil, unlike WD-40.
Unlike guides that suggest you have to crush horsetail leaves before spraying them with WD-40 in order to kill the plant, you can simply spray Crossbow onto horsetail. The pesky weeds will be killed in 7–14 days. Plus, Crossbow won’t harm grass.
Can WD-40 Kill Plants?
WD-40 is not a good weed killer because it was not designed to kill weeds. WD-40 can harm the aboveground portion of plants but does not enter the plant’s system and kill the roots. So, unwanted weeds sprayed with WD-40 may appear to shrivel and die, but they will often grow back.
- WD-40 sprayed on a plant will not kill it down to the roots.
- Weeds sprayed with WD-40 typically grow back within weeks or months.
- If you soak the soil with WD-40 to kill a plant’s roots, the soil will be poisoned for years.
- Use a herbicide that kills plants to the roots but does not poison the soil.
If you use a large enough quantity of WD-40 to soak the soil and kill plants to the root, you will poison the soil for years to come. Soil soaked with WD-40 won’t support plant or grass growth. So, WD-40 either won’t kill weeds permanently or it will destroy your soil. It should never be used as a weed killer.
How Do You Get Rid of Horsetails Naturally?
If you want to get rid of horsetail the natural way, your best bet is to pull it up wherever it sprouts. For best results, dig down and remove as many of the roots as possible. Because horsetail develops massive, tangled root systems, this can be a big job. If you continue to hand-pull horsetail the plant will eventually exhaust itself and die.
- Hand-pulling horsetails, including as much of the root as possible, is the best way to kill it naturally.
- Homemade weed killers are ineffective against horsetail.
- A commercial brush-killing herbicide is the best way to kill horsetail quickly.
Horsetail is a particularly nasty weed. It resists most weed killers except for tough brush killers like Crossbow. Homemade weed killers don’t do much good. There are no shortcuts when it comes to tackling horsetail through natural methods.
Can You Kill Horsetail Weeds with WD-40?
WD-40 is a very poor choice as a horsetail weed killer. The reasons for this are:
- WD-40 sprayed on horsetail leaves will kill leafy growth but won’t stop the plant from growing back from the roots.
- Soil doused with WD-40 will be poisoned for a long time, preventing any plant growth.
- Systemic herbicides, such as Crossbow, kill horsetail growth and roots but won’t harm your soil long-term.
WD-40 is an excellent lubricant and has dozens of uses. However, killing weeds isn’t one of them. Use weed killers to kill horsetail. It’s one of the toughest weeds around and needs to be treated with a powerful brush killer to wipe it out permanently.