I have 5 year old bearberry that is suddenly turning black. Our last summer was the hottest, driest in history if that's relevant. Do I have a problem?
First (before I forget) zone refers to your USDA plant hardiness zone, which according to the information is 9a. https://www.gardeningknowhow.com/planting-zones/usda-planting-zone-map.htm
On the subject of bearberry, climate extremes could definitely cause such symptoms as blackening of the leaves. The heat and dryness could easily have stressed the roots, then the shorter days and cooler temps of winter might have allowed a fungus to start. You might start some cuttings in pots, to use as replacement plants in the spring. Otherwise, basically hang in till the days grow longer, cut out the blackened parts, and you should see regrowth. This article has some tips on bearberry: https://www.gardeningknowhow.com/ornamental/groundcover/bearberry/growing-bearberry-plants.htm
I will be planting a hanging basket (trough) outdoors using a coco basket liner. I'm planting bearberry, which doesn't like transplanting, so I need to know how long the coco liner will last, or should I use something else? This plant likes dry conditions.
Coconut coir liners are considered to be incredibly durable and can be reused for many years if carefully handled. And since your plant favors dry conditions, then you have the extra assurance of your coco liner's longevity.
For more information about coco liners, please visit the following link:
https://www.gardeningknowhow.com/special/containers/coconut-planter-liners.htm
Would bearberry be an appropriate choice for the area between curbing and sidewalk on an arterial roadway? I was thinking it would be a better choice than the grass that is there now, as it is an evergreen, seems to be hardy, and will propagate if need be to fill in areas. We have approximately 18-24" wide strips and the thought was that we could create a consistent viewscape along the length of the town corridor.
Bearberry ground cover is an excellent choice for your growing zone and location.
Bearberry is tolerant of salt, so a location near a road or sidewalk is suitable.
Here is a link with more information.
https://www.gardeningknowhow.com/ornamental/groundcover/bearberry/growing-bearberry-plants.htm
I live in Richmond, Virginia and am having bearberry installed in my front yard. I know wildlife love the berries, but do deer eat the foliage? If so, what can I do to discourage it?
Bearberry foliage is considered deer-resistant, so it shouldn't be much of a problem. If the deer do end up being a problem, here are some ideas on repelling them:
https://www.gardeningknowhow.com/plant-problems/pests/deer/deer-repellents.htm
I have bearberry on the hill on my property, it's in sandy soil and I haven't done much with it over the years (it's about 1o years old now) has spread beautifully but I've noticed in the past two years a lot of dead spots. What do I do about this, clip it back, or what?
You can clip it back with no problem. I would also add wettable sulfur into the soil around it. This sounds like it may be coming down with an infection. Wettable sulfur will help treat this.