I have at least 20 hollies around my home in flower beds. Over half of them are dying. What can I do? They were beautiful. Now they are all dying!
Holly can suffer from environmental issues and they are susceptible to some insects, bacterial or fungus diseases.
Inspect the plants more closely to help diagnose the issue.
Are there insects or leaf spots?
Is their yellowing of leaves or dry browning area of the shrubs?
Here are some articles that will help you.
https://www.gardeningknowhow.com/ornamental/shrubs/holly/diseases-of-holly-bushes-pests-and-diseases-damaging-holly-bushes.htm
https://www.gardeningknowhow.com/ornamental/shrubs/holly/holly-problems-holly-leaf-spot-or-holly-tar-spot.htm
https://www.gardeningknowhow.com/ornamental/shrubs/holly/holly-yellow-leaves.htm
https://www.gardeningknowhow.com/ornamental/shrubs/holly/leaf-scorching-in-holly.htm
These hollies have shiny, elongated, dark green, smooth edged leaves with white flowers and no berries.
My holly bush has holes bored into the thick, main trunks close to the ground. Although it continues to have new growth, the bush has been declining in health over the past few years, despite my pruning and removal of dead leaves and branches. There are no visible signs of bugs or webs. The one next to it looks healthy and green (same soil, sun, water, etc). I am not sure what is causing the holes, nor if there is some way to help the plant other than cutting it back to the base.
Holes in the trunk or branches generally indicate a borer insect.
Here are some links with more information.
https://www.gardeningknowhow.com/ornamental/shrubs/holly/diseases-of-holly-bushes-pests-and-diseases-damaging-holly-bushes.htm
https://www.gardeningknowhow.com/ornamental/trees/tgen/tree-borer-insects.htm
https://entomology.ca.uky.edu/ent43
Holly leaf scorch or winter leaf burn: Should leaves be removed?
Yes, you can prune any dead or diseased branches and leaves right away.
Do this when the plants are dry and during dry days.
https://www.gardeningknowhow.com/ornamental/shrubs/holly/leaf-scorching-in-holly.htm
Will a Holly bush survive in Revelstoke, B.C.? I'm unable to find any information on the regions of survival for Holly bushes.
Your growing zone is 6a.
There are some varieties that will work in your zone.
American Hollies:
Dan Fenton, Hedge Holly/Ilex Opara, Morgan gold, Old Heavyberry.
Japanese Holly: Beehive
China and Blue Holly: China Girl/China Boy, Blue Prince/Blue Princess, Blue Wave, Gypsy Holly, Stormy, Wave Crester and White Cap.
What is causing the leaves on my holly bush to dry up and turn gray? Multiple branches have dead leaves. The bush is over 15 ft tall, had lots of berries in the winter, but now looks as if it's dying.
It sounds like your plant has powdery mildew. This article will help:
https://www.gardeningknowhow.com/plant-problems/disease/powdery-mildew-homemade-and-organic-remedies.htm
In the case of shrubs, it would also be a good idea to do some pruning to allow the interior of the plant to be more open so that the air circulates better. Better air circulation will help with keeping the fungus away. Here is an article on how to do that:
https://www.gardeningknowhow.com/ornamental/shrubs/shgen/thinning-cuts-in-pruning.htm
What pest is on my holly bushes? They are white and the size of a piece of rice. There are thousands of these white 'things' on the holly bush leaves in flat layers, as many as 20 on one leaf. Nothing else in the garden seems to be infected with these nasty things. What are they and what can I do to eliminate them?
I've culled a few different possibilities for you.
The eggs of white flies:
Photo: http://greenscenelandscape.com/images/whiteflyeggs2.jpg
More info & treatment: https://www.gardeningknowhow.com/plant-problems/pests/insects/whitefly-control.htm
Cottony camellia scale:
Photo: http://www.gardenatoz.com/media/51523/IlexScale5808s_500x333.jpg
More info & treatment: https://www.gardeningknowhow.com/plant-problems/pests/insects/control-plant-scale.htm