Garden tip: Should you put banana peels in your soil?

Recently, I’ve been seeing advice on Facebook about adding banana peels to your soil for potassium. Bananas and their peels do indeed contain potassium, which is a major nutrient for plants. The other major nutrients are nitrogen and phosphorous.

Unfortunately, nitrogen is needed to break down the peel, making the nitrogen unavailable to the plant.

Another disadvantage: Adding banana peels directly to the soil may attract unwelcome varmints. It’s OK to add banana peels to your compost bin.

Two other myths that master gardeners have debunked are that adding coffee grounds will help acidify the soil and that eggshells are good for the compost pile. The truth is that fresh coffee grounds are acidic, but used grounds are not. And you would need a huge amount of eggshells to make any changes to the soil.

— Katie Martin, UC Marin Master Gardeners