July 2021 – Sometimes the Best Medicine is No Medicine at All

Pill IconAt this time of the year, plant diseases are in full swing.  When you see diseases in your garden, a natural tendency is to want to do something to make things better.  In some instances however, ignoring the problem and doing nothing can be your best course of action.  Here are my picks for plant diseases where turning a blind eye (at least right now) will not significantly harm your plants and will make your life easier and less stressful.

Powdery mildews

On most plants, powdery mildews don’t do much damage.  Ignore them now and concentrate on good fall clean up to reduce problems with these diseases next year.  For plants such as phlox, bee balms, cucumbers and pumpkins, powdery mildews can be more problematic.  You may want to consider growing powdery mildew-resistant varieties of these plants in the future.

Tar spot

This disease of maples can be visually alarming but is another disease that typically has little impact on overall plant health.  Just be sure to collect infected leaves in the fall and burn (where allowed), bury or hot compost them to help reduce problems with the disease next year.

Cedar-apple rust

Seeing bright yellow or orange spots on your crabapple leaves?  If so, you’re likely seeing this disease.  Spraying fungicides to control cedar-apple is a total waste.  Save your time, money and energy and prune out the galls on junipers caused by the disease (and the source of the spores that infect your crabapples) or alternatively, just remove nearby junipers

Remember. . . Before choosing a control strategy, know thy plant disease.

Need more information?

For more information on plant diseases and their management, check out the UW Plant Disease Facts, available at https://pddc.wisc.edu/search-fact-sheets/ or contact the PDDC at pddc@wisc.edu or (608) 262-2863.