I maintain a professional technology park and am responsible for total grounds maintenance. The one area I'm having trouble with is the annual color beds (which is NOT the problem to have, everyone notices flowers!) Heres the situation: There are (9) full sun, poor soil, overhead irrigated, median plantbeds. The irrigation covers both junipers and any flowers. The owners have insisted on the exact same annuals each season (7years total). 1. Pacifica Red and White Vinca each summer. 2. Majestic Purple and Yellow Pansys each winter. Heres the problem: The Vinca crops have been in decline for several seasons. They tend to yellow, often the stems turn black and have low numbers of blooms. I have observed many brown/yellow vinca with tiny new green leaves trying to grow. These problems vary from bed to bed, some beds thrive at one end and are dead at the other. Snapshot herbicide was used as a pre emergant for a couple of seasons (have since heard that was a big no no). My Questions: 1. Could the irrigation be the cause of all of this? 2. Could soil variations be the source of inconsistency? 3. I've heard you can't plant Vinca every year do to a "Vinca root fungus"? 4. Is Snapshot responsible for the declined health? 5. What is the best resource on the net for these problems? Ironically the Pansys do just fine. I have suggested that all these factors are possibly responsible and we should experiment with other flowers. In short: How do I fix this problem and exceed this customers expectations?