:strip_icc()/101022095_preview-d2524c7aee4b4c7a9027522e7c27a2c4.jpg?w=1920&resize=1920,1056&ssl=1 "Should You Use Boiling Water to Kill Weeds? Here’s What an Expert Recommends")
Heat is a known way to kill weeds. You can buy flame weeders that emit a stream of propane-powered fire or steam weeders that blast out super-heated steam to destroy weeds. Both are suitable methods for killing weeds without using herbicides or chemicals. However, you don’t have to buy one of these tools to use heat as a weed killer in your garden.
Boil a kettle of water and pour it on the weeds you want dead. Boiling water works on contact, killing the part of the plant it touches. Here’s what you need to know about using this organic weed-killing method safely and effectively.
Chelsea McKinley is a plant health care specialist at the United States Botanic Garden in Washington, D.C. She holds a B.S. in Environmental Horticulture Science.
Weeds That Boiling Water Kills
“Boiling water works best on smaller plants, seedlings, and immature plants,” says Chelsea McKinley, plant health care specialist at the U.S. Botanic Garden in Washington, D.C. “Anything with a deep tap root or an extensive root system is going to be difficult to control with heat.”
In other words, you would have to dump a lot of tea kettles of boiling water on a big, well-rooted dandelion or poison ivy grown into a six-foot woody vine to kill them. “It won’t work well on woody weeds,” McKinley says.
How to Apply Boiling Water to Weeds
McKinley recommends boiling water in a tea kettle so you can pour the water precisely on the weed you want to kill. Boiling water kills or severely damages any plant it touches, so you don’t want to miss with your pour and hit plants you want to keep. Using a tea kettle also reduces the risk of spilling or splashing boiling water on yourself.
Pour enough water on the plant to saturate the leaves, stems, and roots. Plan on re-treating a week to 10 days later. A single application of boiling water might not kill the entire weed, especially if it has deep roots.
Use a potholder when handling the tea kettle of boiling water and beware of splashes and spills to protect yourself from severe burns.
Where to Use Boiling Water as a Weed Killer
Boiling water is tricky to direct onto very specific targets. For this reason, McKinley recommends using it to kill weeds in cracks in driveways, pavement, and patios. “I wouldn’t use boiling water in a big bed of plants,” she says, but you could use boiling water to eliminate weeds between the rows of a vegetable garden.
Safer Ways to Kill Weeds
If organic control is your goal, there are safer and easier ways to kill weeds than dumping boiling water on them. McKinley recommends weed-killing sprays made from citrus oil extracts. Weed killers made with a compound called d-Limonene kill a wide range of weeds on contact. “It’s safer than handling a pot of boiling water,” McKinley says.