Q: My inpatients on the north side of the house were beautiful and almost overnight they became leafless stalks. I've seen this before but not till later in October. Is there something wrong or has the plant just finished for the season. All the others are still full and blooming, only the one section is bad.
You may have impatiens downy mildew. Remove the plants roots and all and seal in a plastic bag and put them in the trash. If the spores were deposited in the soil you will not be able to replant for 5 to 6 years. Best Nancy