Natural Cleaning Method for Patio Stains
Patio stains can vanish in just five hours using a simple, natural household item that many people already have in their kitchen. Natural cleaning influencer Nancy Birtwhistle has shared her preferred method for cleaning patios without harsh chemicals, and garden experts agree with her approach.
Algae, moss, black spots, and general grime can accumulate on patio slabs over time, making them slippery and giving gardens a neglected appearance. While pressure washers can remove grime quickly, they can also damage paving if used incorrectly.
Soda Crystals and Eco-Friendly Washing Up Liquid
Instead of specialist patio cleaners, Birtwhistle recommends using soda crystals—also known as washing soda—combined with a small amount of eco-friendly washing up liquid. Soda crystals dissolve greasy marks and break down the organic film from algae and grime that clings to outdoor stone. The washing up liquid adds gentle surfactants that lift oily residues and help the solution spread evenly.
In an Instagram video posted to her account @nancy.birtwhistle, she demonstrated the process on her natural stone patio, which she noted cannot be treated with acidic or harsh products. Her patio was heavily stained with green algae and dirt.
Step-by-Step Cleaning Process
First, Birtwhistle wet the patio using a watering can filled with rainwater. She then sprinkled several tablespoons of soda crystals over the entire surface. Next, she added a small drizzle of eco-friendly washing up liquid. Using a stiff brush, she scrubbed the patio thoroughly, working the solution into the stone. She warned that power washing is not ideal for natural stone because it can make it more porous.
After scrubbing, she did not rinse the solution but left it to sit on the stone. Since rain was forecast for the evening, she did not need to rinse; however, in dry weather, the solution should be rinsed away after several hours. Checking the next morning, she found the patio had transformed, looking “absolutely gorgeous” and almost brand new.
Expert Endorsement
Gardening experts at STIHL also recommend soda crystals for cleaning patios. They stated: “A mixture of soda crystals and water is an effective but strongly alkaline cleaning agent. It can be used for particularly dirty patios.” They advise using 10g of soda crystals per 1L of water, spreading the mixture with a broom, leaving it for five to six hours, then rinsing with clear water from a garden hose.
