Baking soda, a common kitchen cupboard staple, offers a cheap and natural solution to banish weeds growing between block paving on driveways. The ingredient dehydrates plant tissues, causing weeds to shrivel and vanish.
Why weeds thrive in block paving
Block paving is a durable and attractive choice for driveways, but the spaces between blocks collect debris and trap moisture, creating an ideal environment for weeds to thrive. Sweeping and cleaning can help remove debris and seeds, but weeds easily take root, especially during summer when warmer weather promotes growth.
How baking soda works
Baking soda, also known as bicarbonate of soda, is a type of salt. It draws out moisture from weeds, dehydrating them and destroying plant cells. According to gardening website The Spruce, “The reason baking soda is effective in killing weeds is that one of its major ingredients is salt. In sufficient quantities, salt's effect on plants is to dehydrate them. If you want to kill a weed permanently, this is one way to do it: dry it out so much that it can't take up water anymore, and the weed will die for good.”
As a natural product, baking soda avoids the risks of harsh chemicals causing soil contamination or damaging nearby plants.
Application tips
Paving experts suggest first wetting the weeds with water before sprinkling baking soda on top, as this helps it stick to the plant. It is best applied after heavy rain. The method should be repeated every four to six weeks to prevent weeds from returning, especially for well-established weeds.
Leading cleaning product supplier Jenny Chem advised: “Expect to see visible effects from using baking soda for weeds within 24-48 hours - leaf browning and wilting. The actual death of weeds can take several days to a few weeks. Direct application of pure baking soda for weeds works best for small patches or weeds growing between cracks in driveways and patios. Start by dampening the weed so the baking soda can stick to it. Sprinkle a generous amount of dry baking soda directly onto the leaves and the base of the plant. Leave it undisturbed for 24 hours so it can work its magic.”
For tougher weeds
For more stubborn weeds, baking soda can be combined with vinegar. The acetic acid in vinegar helps break down plant cells and strip moisture, enhancing the desiccating effect. Jenny Chem added: “Remember, many weeds are going to be impervious to baking soda alone. You can combine it with vinegar for those tougher weeds to enhance its desiccating effect. Vinegar is highly concentrated in acetic acid, a powerful natural herbicide that breaks down plant cell wells. This dynamic duo really sucks the life out of the weed and gives you a better chance of successful eradication.”
