How To Clean Wood Planters Without Damaging Them

Wood planters aren't exactly high maintenance — but neglect them for long enough, and you'll find yourself with a yard full of rotting planter boxes instead. Along with protecting the wood from moisture, regular cleaning is an essential part of keeping your wooden planters in good condition. It's a simple process: all you need is soap, water, and a soft brush or cloth.

Ideally, your wood planters should get a good cleaning with soap at least once a year. Realistically, you can take the opportunity to clean the inside of a planter whenever it's in between uses — when you prep last year's planters for a new season of gardening, for example, or when you're potting up a plant. That's the most vital time to clean anyway since fungi and insects can remain on the planter, increasing the likelihood that diseases are transferred from one plant to another. You can also clean the outside of the planters regularly to maintain their durability and aesthetic appeal.

With other types of planters (like plastic or clay), disinfecting may also be part of the process. But the most popular types of wood for planters are naturally resistant to fungi and bacteria, and harsh chemicals like bleach can weaken wood, so they're best used sparingly if at all. Instead, stick to milder soaps.

Dilute a mild soap, such as dish soap, in water, and use the solution to scrub your wood planter with a soft brush or cloth. In addition to scrubbing away the leftover dirt, make sure to remove any algae, moss, or mineral deposits that you see on the wood. Then rinse the planter dry; try not to fully soak the wood to prevent later moisture issues. Allow it to fully dry before you add soil and plants back in.

Not only should you avoid harsh chemicals, but you also shouldn't use a pressure washer to clean raised garden beds or wood planters without special precautions. You may create splinters, dents, or an uneven surface if the pressure is too high, too close to the surface, or in the opposite direction of the wood grain. For more delicate types of wood, such as planters designed for indoors, even a regular garden hose may cause damage; use a dry or damp cloth to wipe them clean instead.

Post-cleaning is a great time to lightly sand the wood and reapply any treatments, oils, finishes, or stains. You can also check for other issues and treat them as needed. For example, you can apply a fungicide to treat fungal infections. If the planter is too large for it to be practical to remove the soil, and you need to disinfect it, consider using soil solarization to keep away pests. Cover the soil with clear plastic and leave it in the sun for four to six weeks.