Pollinator Safe Plant Disease Management
Powdery mildew, rust and leaf spot can annoy the gardener, but spraying with fungicides can contribute to native and honeybee decline.
Bees depend on native yeast to ferment nectar they combine with pollen to create bee bread. Bees depend on bee bread for survival. So, when we spray our plants with fungicides we can kill the natural yeast, preventing bees from making bee bread, causing them to starve.
Always think before you spray. Prevent problems by growing disease resistant varieties. Tolerate damage that is strictly cosmetic.
If you decide to spray, do so before or after plants flower. Don’t apply systemic fungicides prior to flowering. These materials are absorbed into the plant and transported to the flowers where they can harm the bees. And never spray on windy days when pesticides can drift onto nearby plants.
A bit more information: When weighing the need to treat plants for disease or insect problems we should all consider these words from Albert Einstein. “If bees disappear from the face of the earth, mankind would only have four years to live.”