Botanical Gardens Director Jeff Gillman interviewed by Country Living
Jeff Gillman, Ph.D., director of UNC Charlotte’s Botanical Gardens, was interviewed by Country Living for “Does Boiling Water Really Kill Weeds? Experts Say Not Quite.”
Boiling water may make weeds wilt on contact, but horticultural experts say it’s neither effective nor safe as a long‑term weed control method. Water hot enough to scorch plant tissue can cause severe burns, and it cools rapidly once it hits soil, reducing its impact. While it may temporarily knock back small weeds, many will regrow within days.
“Hot water kills the top of the plant quickly, so it appears to be very effective, and we think of it as safe,” said Gillman. “Unless you have a cauldron, you are probably not going to be able to apply enough hot water to the ground to increase temperatures enough to kill roots under the surface of the soil.”
Gardeners seeking non‑chemical solutions have more reliable options, and digging weeds out by the roots remains the most effective method. In addition, organic mulch suppresses weed growth, moderates soil temperature and makes any new weeds easier to pull. Then regular hand‑weeding can help prevent seedlings from spreading, while planting garden beds densely reduces open space where weeds can take hold.