Homeowners and gardeners alike plant roses to create a yard or garden awash with color and fragrance. Growing roses is definitely a job for a new gardener or a master gardener. Unfortunately their are a few diseases new and some seasoned gardeners need to defend their roses against -- powdery mildew.
Unless you have purchased a disease resistant variety of roses, roses are susceptible to diseases such as powdery mildew. Even if you did buy disease resistant roses, your rose-bushes can still end up with this fungi. Disease resistant means they will resist disease better than other varieties, it does not make your rose-bushes immune to it. Powdery mildew looks like a gray or white dust on leaves and canes. It usually starts out looking like spots on the leaves. Powdery mildew will affect the growth of your roses, the flower buds and will stop new shoots. Powdery mildew usually develops because of highly humid weather conditions, the rose-bush is planted in the shade, the roses are planted too close together and your rose-bushes have become too dense. Powdery mildew will kill infected leaves and canes and even your entire rose-bush. Of course the best method to control powdery mildew is to prevent it by pruning and thinning out roses, properly spacing your rose garden and planting roses in an area that gets the correct amount of sun for the variety.
You can make your own spray to rid rose-bushes of this damaging fungi. These natural alternatives are far less expensive than store bought anti-fungal sprays and are oftentimes just as effective. It is also natural, no harmful chemicals which alone makes making your own spray worthwhile.
Treating Powdery Mildew
Remove badly damaged leaves and canes. Throw them in the garbage or burn them. Do not add diseased leaves and canes to your compost pile because you will spread the spores and infect other plants.
Making Your Own Spray
Fill a large spray bottle with very hot water and add approximately 1/2 of a teaspoon of ground cinnamon.
Allow the cinnamon to steep overnight.
Before using the spray on the entire rose-bush, spot check to make sure the cinnamon won't burn your rose-bush. Be sure to spray both sides of the leaves.Spray one leaf with the mixture and wait 24 hours. If the leaf looks ok after 24 hours, proceed with spraying. If the leaf looks burnt, try the next method.
Generously spray the entire rose-bush and surrounding rose-bushes.
Reapply the mixture after a rainfall.
A Second Spray Recipe
Fill a large spray bottle with very hot water and add approximately 1/4 of a cup of powdered garlic. Do NOT use garlic salt.
Allow the mixture to steep for an hour or two.
Generously spray the entire roses bush.
This is best done early in the morning.
Repeat after a rainfall.
Many times natural sprays are highly effective, but sometimes a fungal infection on the rose-bushes needs a stronger remedy than what your kitchen can offer.
Choose a ready to use spray or one that requires dilution and spray the rose-bushes thoroughly according to teh fungicide manufacturer's directions.