It’s time to think of backyard barbeques and entertaining. If your patio umbrella is dirty and dingy you can spruce it up by mixing 1 gallon of water with 1 cup of white vinegar and 20 drops of tea tree oil. Spritz this onto the umbrella with the spray attachment on your hose. The mold and mildew will be attacked by the vinegar and tea tree oil, even those that formed in the folds of the umbrella. After several minutes, rinse off with the hose using plain water. Open the umbrella and let air dry.