Homemade Remedies to Control Insects and Diseases of Roses

Are there any good homemade remedies for controlling bugs and diseases on roses?

Homemade remedies make me nervous.  Many of the products used are not developed for or tested on plants and may cause damage.  Plus the product formulation may change and the once safe household product now damages plants.  I stick with University tested materials and recommendations.  Many Universities and chemical companies are researching and testing more eco-friendly products so the future is looking good for those of us trying to garden and be kind to the environment.  

One "homemade solution" that comes to mind is baking soda.  Cornell University found that baking soda was effective at controlling powdery mildew.  Mix one tablespoon of baking soda and one teaspoon of horticulture oil (formulation labeled for use on actively growing plants) or insecticidal soap (these help the spray stick to the leaves) in one gallon of water.  Weekly applications will keep mildew under control.  I have had reports of this mix suppressing black spot as well.  The oil and insecticidal soap also help control many of the insects that feed on roses.  

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