Question
We recently planted a black chokeberry bush in our backyard.  We live in Northern New Jersey where the weather has been hot and humid over the last several weeks.  The plant was doing great until last week when I noticed white powdery substance on the leaves which I thought to be mildew.  I purchased an organic product online.  However, the plant seemed to be getting worse so after looking at some websites I mixed together hydrogen peroxide/baking soda and water 2 tbl of 3%/2 tbl of soda and 4 to 6 cups of water and sprayed the plant.  The mildew is gone but now many of the leaves are turning black and appear to be dying.  What should I do to save the rest of it and should I apply the product that I purchased for the mildew when it arrives.
thanks


Answer
Hello Liz

This definitely sounds like powdery mildew and the weather conditions you describe - hot and humid - are perfect for this condition.  

Chokeberry (Aronia) likes a moist, well drained soil and with the weather being hot, it may have dried out, which will be putting the plant under more stress.

Things to do now - pick off as many of the affected leaves as you can - bag and bin them.  Give the plant a really good watering around the roots - onto the ground, not overhead.  Then spray with a fungicide formulated to combat this condition.  If the organic product you have purchased online doesn't work, you may have to consider using a chemical based product.

Hopefully your Chokeberry will come through this.

Gill