Esperanza plants are dying
I have four Esperanza plants along my back fence. Recently, the one on the far left started wilting and then turning brown and dying. I went out and trimmed all the dead stuff out, it has left me with three shoots. Now the esperanza next to it is starting to wilt. We water once to twice a week. The plants are located in a flower bed raised up about a 1 1/2 feet for additional soil, and covered with bark. The soil we used in the beds was just plain sandy loam that we picked up at lowes. These plants have been at this location for about 10 years, but we placed the beds around them only 3 years ago. Every year I add some bark, just enough to cover the old. I would like to save these plants because they are so beautiful.
I would suspect that a fungus is attacking the roots or leaves of the plants. Treat the leaves with a fungicide and mix some of the fungicide into water and water the plants with it. I will say that if it is a fungus on the roots, they tend to be more resistant to fungicides and may not fix the issue. In which case, it may be best to remove the affected plants before the fungus spreads anymore.
Does the site receive a lot of water or stay somewhat moist? The location may have been a little too wet, which could spawn fungal issues. I would recommend either that you mound up the soil in that location some so that the plants will be sitting in drier soil, should drainage be an issue.