We have had two very healthy Portugese Laurel trees growing in our garden, that were here when we moved in 10 years ago (so I don't know how old they were). Last summer, they showed signs of a problem - the leaves started to whither and this spring did not produce any new buds. Before I plant anything else in the bed to replace them, is there some soil testing or something else I should do to determine what killed them? Do such plants have a natural life expectancy and they just died of "old age"? It's odd that they would both die at the same time. Any advice would be helpful.
Prunus lusitanica is relatively long-lived in its native environment, eventually forming picturesque, oak-like trees. In the Vancouver area, there are few reported problems with Portugese laurel (other than overly vigorous growth). If the plants are failing to set buds, this suggests a serious problem, either at the roots or around entire stems (e.g., girdling). Without obvious evidence above ground, chances are the problem is water-related. Has the soil water situation changed drastically in the past few years? Drain tiles installed? New garden bed? New turf? Construction nearby?
Thanks, Douglas for the quick response, and you may have hit on the cause of my problem! Last spring, I extended some drain tiles in an area about 6 - 10 feet from the trees in question. I hadn't expected that it would have such an effect on the water flows in the garden. Theer are other bushes in the same bed, like rhodos and Lily of the Valley bushes, but they have shallower root systems, I suspect.
as a general rule prunus lusitanica needs little or no water once it is established. lightly prune back now to see if you can encourage new growth. i would give it one more light feeding before fall sets in
Unhappy Laurels Cutting through or burying the roots would probably be the problem, unless the area is now soggy from the pipes emptying into it. Fertilizing is appropriate when there is a nutrient deficiency, unlikely to be the case here. Also, fall is the best time to fertilize hardy stock, so I certainly wouldn't taper off fertilizing of plants as fall approaches.
