We have two very large, spreading, tall 50-year plus yews at the corner of...
We have two very large, spreading, tall 50-year plus yews at the corner of our property which have turned quite bronze on top, less so on the sides, and remain green on the lower, more shaded areas facing our house. The foliage seems healthy except for the color. The street sides of the yews face east/south. Near neighbors have large yews hedges, with the same exposure, but they are fully green with no bronze. My question: Are they dying of old age, or is the bronze caused by extreme weather changes, or is something wrong with the soil? We did have a lot of debris (ivy & leaves) cleared out from under the yews a year ago and added holly tone and mulch. Thank you for taking this query. A.K.
If the browning occurred over this winter, it may be a result of the severe weather. We are seeing and getting reports of a lot of winter burn on evergreens. If the shrubs didn't have plenty of moisture around its roots when the soil froze this winter, lack of moisture could have contributed to the problem. (We did have a very droughty early fall last year.) Wait until spring. It might green up fine. Do not prune off any brown material unless you are certain that portion is dead. This year, you may want to water during extended drought. Yews do not like their roots to sit in water (constantly sodden soil), but water is also the most critical factor in all plant health. Do not add more fertilizer.
Also yews do not like acidic conditions and should not be fertilized with an acidic fertilizer like hollytone. Yews like a more neutral pH. The ideal pH for them is about 6.5.
Clearing around the base of the yews should not have harmed them; it should have benefited them. However, mulch should never be piled on the bark at the base of shrub or tree trunks and it should not be more than 1-2" deep. Be sure the mulch is not contributing to the yew's stress.
Yews can live for a hundred years, however that is under optimal conditions.