Can you tell me why my 20 ft holly tree has flowers but no berries, please?
Do you have both male and female plants? If not, this could be your problem. Poor pollination may be to blame as well. This article should also help: https://www.gardeningknowhow.com/ornamental/shrubs/holly/holly-bush-no-berries.htm
I live in northwest Florida. My Holly bushes are growing up and outward, causing an overhang of the lawn. Besides looking extremely top-heavy, they are thin at the bottom and reaching up to 7 ft tall. How far can I cut them back with the bottom parts being so thinned out?
While most pruning is done in December, you can still prune now but it may affect the number of berries produced this year. Hollies, as with most shrubs, can be pruned back by a third of their growth. Any more than that will likely harm the plants. This article should help: https://www.gardeningknowhow.com/ornamental/shrubs/holly/trimming-holly-bushes-how-to-prune-holly-bushes.htm
I have a holly tree (JC Van Tol) with good berries, but over the last few weeks many of the leaves have started to curl from the tip ends. Some are now fully curled up. What has caused this and what do I do about it?
This is likely due to black spot fungus, which can affect many types of plants. Neem oil is an effective treatment for this fungus,as well as other types, and will help with pest too. Here is more information: https://www.gardeningknowhow.com/plant-problems/disease/black-spot-fungus.htm
https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm
Recently moved into home that has a massively overgrown Holly shrub, stands about 12 ft high and has 3-6"+ branches that "W" out from ground level. The leaves/berries are producing and the ends of the branches that are still living. Would like to prune dramatically can you advise on possible techniques so not to lose the entire shrub/tree?
While most pruning is done in December, you can still prune now but it may affect the number of berries produced later this year. Hollies, as with most shrubs, can be pruned back by a third of their growth. Any more than that will likely harm the plants. This article should help: https://www.gardeningknowhow.com/ornamental/shrubs/holly/trimming-holly-bushes-how-to-prune-holly-bushes.htm
Will the roots start to crack concrete if planted close to a porch?
Most types of holly shrubs have shallow root systems and should not cause any issues.
I have a holly tree that has not grown any foliage for a while now (two years). Is it worth trying to salvage the tree or should I just presume it has died?
As long as there is still green in the branches, it's still alive. This article may also help: https://www.gardeningknowhow.com/plant-problems/environmental/how-to-tell-if-a-plant-is-dead-and-how-to-recover-an-almost-dead-plant.htm
I have a female bush that gets berries but the male bush does not.
Only the females produce berries.
Well, it's kinda like men not having babies. This article is helpful: https://www.gardeningknowhow.com/ornamental/shrubs/holly/holly-bush-no-berries.htm