I live in the low desert of AZ. I have a flower bed running the length of the front of my home. The landscapers laid down rock mulch. I have vincas planted in it. Overall, they do well, but about once a week one will suddenly shrivel up and die. I water from the bottom every day. The deaths seem to run down the line, one next to each other. We plant vincas year after year. |
Vinca can usually take the heat, but they are annuals and they do die out when their lifecycle is finished. This can vary by as much as 3-4 weeks between plants, but eventually they will all die out. What might be hurrying them along is the reflected heat from the rock mulch. It absorbs and reflects the heat and in the last few weeks things have been pretty hot in Casa Grand. Add the wind and the rain and it may be too much for your vincas. You might try growing portulaca in the bed to see if it does any better. It seems to thrive in the desert heat. Best wishes with your garden bed. |