We have not heard about any widespread issues with holly berry production this year, though insect-pollinated plants can vary in their berry production greatly based on weather. Cooler and wet conditions can keep bees, flies, moths, and many other pollinators grounded, and since flowers have a finite lifespan once opened before they become infertile and fade, a missed pollination window some years can result in poor berry set.

If a plant was too stressed the prior year, such as by drought, flower buds may fail to form or may form but then abort (die, dry up, and fall off) anytime before when they would open the following spring. American Holly blooms on "old wood," which means the stems that grew as new growth this year will be producing flower buds next year (or later). Pruning can also interrupt blooming on species that flower on old wood, since trimming removes some of that flower-age growth.

Another condition that affects how many berries ripen is anything that stresses the plant between pollination and fruit ripening, which often revolves around drought or under-watering. One of our native holly species, Winterberry Holly for example, is known for dropping unripe berries during summer if the plants become too dry. American Holly is more tolerant of drought, though still prefers to stay more evenly moist in the root zone. All you can do for now is to just keep monitoring the plant for watering needs to reduce any drought stress as our ongoing deficit of rainfall continues.

Miri

Thank you very much for your helpful comments Miri. It certainly has been very hot and dry in my area, so drought may be the culprit.

You're welcome.