Salvia Leucantha & Nandina Domestica Dying
First let me start off by saying I am not much of a gardener... I currently have a few plants that are not looking so great, and I'm not sure what went wrong, or if there's anything I can do. I am located in Tucson.
Everything is on a drip system. It waters on odd numbered days for 2.5 hours. Everything was lightly pruned 2/2009. I lightly fertilized with "arizonas best" in 7/2009.
I have 4 salvia leucantha (mexican bush sage) in a corner that get full sunlight. They looked great when they were planted a year ago, but this year 1-2 started looking dry/dead'ish, and then finally 1 completely died. The second looks bad, and the other 2 are alive and blooming, but much smaller than they used to be. Not sure if its over/under watering, bugs, disease, etc. The first one to die is lighted at night via a low voltage light - not sure if that attracted bugs or not. There are two drip lines running to each salvia. Not sure if they are 1GPH each or more. Links to pictures below:
Salvia when first planted: http://i232.photobucket.com/albums/ee189/bugman74/CIMG2254.jpg
Salvia prior to pruning (only removed long stalks): http://i232.photobucket.com/albums/ee189/bugman74/CIMG2962.jpg
Salvia last month: http://i232.photobucket.com/albums/ee189/bugman74/CIMG3330.jpg
One dead (dug it up today): http://i232.photobucket.com/albums/ee189/bugman74/CIMG3426.jpg
Others blooming, but dont look as big and happy: http://i232.photobucket.com/albums/ee189/bugman74/CIMG3425.jpg
Any thoughts? It doesnt look like bugs. Did I over-water? Did I stress them out with the fertilizer?
I think I'm going to re-plant. Should I do it now, or is there a better time?