Copper penetrates the leaf surface and prevents germination of spores so the fungus cannot spread. Reapply as directed on the product label. Spray a copper-based fungicidal soap on the leaves, coating the top and bottom leaf surfaces. Repeat every two weeks until existing spots stop enlarging and new spots no longer appear. Using a spray bottle, spray on tops and bottoms of leaves until the mixture drips off. Dissolve ½ teaspoon of baking soda and one teaspoon of liquid soap in a gallon of water. Organic options won’t kill the fungus, but will prevent it from spreading. It is recommended to start by applying organic treatment options, working up to the more potent synthetic, chemical fungicides if necessary. However, if much of the foliage is affected and defoliation occurs, the plant will benefit from getting rid of the infection. Solutions: In minor cases of brown spot, there isn’t any need to treat the disease. Even if the number of leaves with infections is relatively large, you should not prune more than 30% of the total number of leaves to avoid affecting the growth of Spanish broom. Pruning can effectively reduce the infection of disease. When Spanish broom grows, if there is aging yellowing leaves and diseased leaves, you need to prune the bottom of the yellowing aging leaves and leaves with spots caused by the infection of disease. Please make sure that the cuts are clean and tidy. Over pruning will hinder the normal and healthy growth of this plant. You can also prune it into a shape you like, but don't prune over 1/4 of the healthy branches and leaves of the Spanish broom. Pruning at the beginning of the growing season allows the plant to have the whole summer to devote to putting new growth into the remaining branches, flowers, and leaves. This timing makes it easy for you to find which branches are not productive and should be removed, since those branches won’t have any buds. The ideal timing is when the Spanish broom has developed buds but the buds have not opened yet. Removing large branches (structural pruning) from your Spanish broom is best done during the dormant period in the winter, while late winter or early spring is the best time for minor maintenance pruning. Also be sure to wear protective gear to avoid injuring yourself during this process. Your cutting implement should be sterilized with disinfectant or a diluted bleach solution before use and between cuts to avoid introducing pathogens to the wound when pruning. A pole saw may be necessary if the branches are higher up. If there are larger branches, you should use loppers or a pruning saw. Many Spanish broom branches are thin and delicate, so you may be able to use regular pruning shears. After you have decided where to cut, prepare the tools. You may want to mark branches with string or tape so you don’t forget where you had planned to prune each branch. It is a good idea to identify which branches you want to prune before taking other steps so you know which tools you need and have a plan from the beginning. Pruning at the beginning of the growing season allows the Spanish broom to have the whole summer to devote to putting new growth into the remaining branches, flowers, and leaves. Removing large branches (structural pruning) from the Spanish broom is best done during the dormant period in the winter, while late winter or early spring is the best time for minor maintenance pruning.

Spanish broom spartium junceum