Rose rust disease is caused by the phragmidium fungus. It is usually first noticed as rust-coloured spots or orange dust on the underside of the leaves of the rose bush. In severe cases, it spreads over the plant, except for the rose petals and roots and can be seen in the soil around the rose bush. It is a serious rose disease and has the potential to kill plants. The best way to avoid rose rust disease is to plant roses where they get plenty of air circulation and sunshine. Also, avoid overhead watering or splashing water on the leaves.
Pour the vegetable oil, liquid soap, Listerine and baking soda into the tank of a 1 gallon garden sprayer.
Add 1 gallon of unchlorinated water to the garden sprayer tank. If unchlorinated water is unavailable, pour 1 gallon of chlorinated water in an open container and allow it to sit for 24 hours. This allows the chlorine in the water to dissipate into the atmosphere.
Pour the apple cider vinegar into the tank. The apple cider vinegar is poured in last so it does not interact with the baking soda and begin to foam or effervesce. Gently shake the garden sprayer to mix the ingredients.
Spray the homemade treatment over the entire rose bush. Concentrate on the underside of the leaves where rose rust disease is usually found.
Prune off any infected leaves before treatment to help control rust disease. Handle infected plant parts very carefully so the rust spores do not become airborne and infect other plants or vegetation. Do not handle uninfected parts of the plants after touching parts of the plant with rose rust disease.