Plant rust is a common fungus that plagues home gardens and major crops around the world. While there are a number of chemical solutions available to treat plant rust, many gardeners prefer instead to use a more natural approach with the household items they are likely to have at hand.
Before getting started, combine the following ingredients into a 1/2-gallon container (double the recipe for a 1-gallon solution) and fill a spray bottle to begin your rust elimination or prevention process.
2 tbsp. canola oil 3/4 tsp. baking soda 1/4 cup white vinegar 1/4 tsp. Murphy's Oil Soap 1/2 gallon tap water
One of the few upsides to having a plant that is infected with rust is that each type of rust fungus is so plant-specific that it probably can't infect plants of another species around it. Like many other fungi, rust is spread through spores that travel through the air, which is why it can appear, quite literally, out of the blue. If you do have a rust infection in the midst of a group of similar plants, however, you must get the infection under control before it can ruin the entire group. When multiple plants are infected, treatment can be difficult and typically requires frequent monitoring to fight its spread.
Like many maladies in the plant world, an ounce of prevention is far more effective than trying to cure the rust after the fact. Rust prevention is a simple process that needs to be repeated about once weekly. Simply spray your solution onto the stem areas and the underside of your plant's leaves--which is where the rust typically begins--until every surface is thoroughly coated. Continue treatment regularly to ensure the continued safety of your valuable plants.
If your plants have already begun to show signs of rust, or even if the fungus is already strangling them, it might not be too late. Begin by removing and discarding every leaf on the plant that shows signs of rust infection. Do not compost these infected leaves when you discard them. By planting infected leaves in the ground, the fungus can still reinfect the plant over time. Finding the leaves to discard is usually simple because of the odd coloring of the rust or the visibly dying leaves that may turn black and become shriveled or curled, making them easy to spot. After you remove the leaves, the plant will be able to use its resources to revitalize the uninfected areas, rather than wasting them on leaves that are already dead or hopelessly dying. When the infected areas have been removed, use your solution to keep the fungus from reattaching itself to your plants.