Best way to kill ‘persistent’ patio weeds – and it’s not salt
“Do not use salt to kill weeds as this can damage paving,” Cass Heaphy, the Digital Director at Paving Direct, told Express.co.uk.
Not only can salt ruin costly paving slabs, salt is detrimental to the soil underneath, which could impact other plants elsewhere in the garden.
Instead of treating weeds that grow between paving slabs with salt, Heaphy recommended the best procedure for getting rid of the unwanted plants.
Heaphy said: “To remove weeds from driveway block paving, start by pulling anything that will come up by hand. For those weeds that cannot be easily pulled up, a weeding tool or scraper is recommended.”
The paving expert continued to reveal the best gardening tips to remove weeds from patio slabs without causing undue damage.
Heaphy said a weeding tool is great for dislodging the weeds from in between paving slabs.
“If the weeds are really persistent, then an organic herbicide is recommended,” Heaphy added.
When an organic herbicide has been applied and worked its magic, “kiln-dried sand” is recommended to fill in between the paving slabs to “help prevent regrowth”.
This is also true of patios but, instead of kiln-dried sand, alternatives include “an epoxy-based jointing compound such as Pointfix for concrete and stone patios”.
For porcelain patios, Heaphy suggested using an “exterior tile grout” to prevent the regrowth of weeds.
The Royal Horticultural Society (RHS) recommended the “application of hot water” to kill weeds.
However, deep-rooted weeds, such as dandelion, “require the removal of their tap root”.
The RHS said: “This can be tricky in crevices or cracks. Specially designed narrow-bladed weeding tools – sometimes called ‘dandelion weeders’ – for tackling such weeds are the most effective.”
Alternative weed removal tools include a block paving knife and a wire-bristled block paving brush.
“Flame guns or flame weeders can work on hard surfaces, especially in warm dry weather,” the RHS added.
“The localised heat ruptures the plant cells, causing it to die back… persistent perennial weeds may regenerate, but should succumb to repeated treatments.”
The RHS echoed Heaphy’s sentiment: “The use of salt to kill weeds on paths and drives is strongly discouraged, as this can cause damage [to other] plants.”