My 5 year old holly trees are full of green berries. Is there some fertilizer or something that will help these turn red by Christmas? This is the very first time they have had so many berries.
Certified GKH Gardening Expert
They will turn red on their own and there is nothing you can do to speed up the process. If you find that they do not turn red at all, you may have holly berry midge, which burrows into the berries and prevents them from turning red. Here is more info: https://www.gardeningknowhow.com/ornamental/shrubs/holly/holly-berry-midge-pests.htm