5 Surprising Ways Baking Soda Can Help Your Garden Thrive This Summer

Eliminate Pests

According to Andrew Levi, CEO and founder of PlantTAGG, baking soda is excellent for getting rid of pesky bugs like slugs and ants because it creates an inhospitable environment for them when sprinkled. Baking soda is a desiccant, which dries out soft-bodied insects like slugs and interferes with the digestive systems of ants. “Ants, in particular, avoid baking soda as it disrupts their ability to maintain scent trails,” he adds.

Levi recommends sprinkling a thin layer of soda around the base of plants or affected areas. Alternatively, mix it with sugar (equal parts) to attract ants, which ingest the mixture and die.

Baking soda can alter soil pH and harm beneficial insects. Additionally, using it on plants with a high salt sensitivity, such as ferns or certain flowering plants, can lead to damage. Levi cautions against using it liberally throughout your garden—but try to limit it to just the affected areas.

Control Weeds

If you’ve got a few weeds throughout your lawn or garden, baking soda may help eliminate them because its high salt content draws moisture, dehydrating and killing the weeds. “You can apply baking soda directly from the container,” says Ryan Walts, training manager at Lawn Squad. “This method can be made more effective by wetting the weed(s) down first to ensure good contact with the baking soda when it is applied.”

You can also mix baking soda and water in a spray bottle (about 1 cup per gallon of water). Walts says this method helps the baking soda stick to the leaves of the target plant, and adding other ingredients like dish soap and vinegar may boost the efficacy. “Regardless of the application method, it is best to apply baking soda when weather conditions are dry with minimal wind,” Walts advises. 

As mentioned earlier, baking soda can be harmful to other plants because it’s technically a non-selective herbicide. “Plus, the build-up in the soil makes it less fertile,” Levi warns. So definitely use it with caution! Also note that more aggressive, invasive weeds will likely be unaffected by baking soda—you may need a more potent herbicide for a permanent fix.

Prevent Plant Diseases

Are your plants prone to diseases like powdery mildew or black spot? It turns out that baking soda can be used as a fungicide to treat those fungal conditions. “Sodium bicarbonate raises the pH level on leaf surfaces, making it more difficult for fungi to thrive,” Levi says. “However, this method is most effective as a preventative measure rather than a cure.”

Levi recommends mixing 1 tablespoon of baking soda with 1 gallon of water, a drop of dish soap, and optionally a tablespoon of vegetable oil. “Spray this solution on affected plants early in the day to allow for drying,” he adds. “It’s important to reapply after rain, but avoid heavy accumulation of sodium in the soil.” Frequent use can cause the plant to absorb too much sodium, which may stunt growth or harm foliage.

Increase Blooms

While many plants (like azaleas and rhododendrons) prefer slightly acidic soil, a few plants (like clematis and forsythia) do well in slightly alkaline soil, and that’s where baking soda comes in. According to Levi, you can use it to adjust your soil’s pH, which helps alkaline-loving plants absorb nutrients more effectively, leading to more vibrant blooms.

Just dissolve 1 tablespoon of baking soda in 2 quarts of water and water your alkaline-loving flowering plants monthly.

Clean Gardening Tools

We’d be remiss not to include how you can use baking soda to clean your dirty gardening tools. Simply make a paste of baking soda and water, then use the mixture to scrub rust or dirt off pruning shears, trowels, and other tools. Keep in mind this won’t disinfect them, which is important if you want to prevent the spread of diseases between your plants, so you’ll need to follow up with your preferred disinfectant.