I have a Culligan water softener system. Once every seven days it purges potassium with water into my flower bed. All my roses have died and nothing I have planted there will grow. I chose potassium over salt because the salt will kill the lawn. What can I plant there that will survive? The area gets morning/early afternoon sun.
The soils are likely overloaded with potassium. Just like other nutrients, the right amount is a very good thing, too much and some unwanted things happen. Too much potassium inhibits the plants ability to take up other nutrients thus they get weak and succomb to disease or just do not get enough other nutrients to survive. I would have your soils tested to see where the levels are at. Then follow the advise of the testing lab on how to balance out your soils again. Potatoes and cabbage are potassium loving plants but also need to be able to take up other nutrients. So it is best to do what is needed to bring balance to your soils makeup.