ANSWER: It can be confusing sometimes. A deciduous plant (tree or shrub) will go dormant (its rest period) beginning when either the weather starts becoming colder (40's to 50's) or when an area experiences a hard frost (temperatures dropping below 32 degrees, usually overnight). It will begin to lose its leaves at this time. Blooming plants have specific periods when they bloom. They aren't always in bloom. Many will bloom either in spring or summer.
"Evergreen" is used to describe plants (trees/shrubs) that do not go dormant and retain their leaves or needles. This generally refers to pines, spruces, boxwoods, junipers, yews and holly. Broadleaf evergreens are plants that retain leaves (very thick leaves) year round. But, they do shed the leaves periodically. This will apply to plants such as azaleas, rhododendrons and photinia.
Perennials are (usually) smaller plants which die completely back to the ground after cool weather or frost sets in, then return the following season. Annuals are plants that you have to set out every year as they will die completely. These include marigolds, pansies, geraniums, and other decorative often flowering plants.
QUESTION: "I have three holly bushes in shade (at least one female and at least one male, though I do not remember whether we have two males or two females), and they have had no berries for the last several years. What can I do to fix this problem?" - Janet Furey
ANSWER: Actually, this is one of the most frequent questions that I receive. I am so used to answering it that I guess I just didn't think about including it in the column or newsletter. Thanks' for the idea. But, so as not keep you in suspense, I'll share it with you now.
Not all hollies enjoy shade. If your varieties prefer sun, the shade can limit any blooming. You would have to move the plants.
One male plant can pollinate 4-6 female plants. But, both sexes must be in bloom at the same time and planted within 100 feet of each other. If several did produce berries at one time, the one holly bush that didn't have berries that year will be the male (male hollies don't produce berries).
Hollies don't usually begin flowering until after the 4th year. If your plants are younger, that might be the reason for no berries.
Hard frosts during their blooming period can cause the blooms to fall off before pollination. Cool and rainy spring weather will limit insects from pollinating effectively. Plants can be covered during blooming if cold weather is anticipated.
Recently I read that too much nitrogen in the soil can cause the blooms to fall off before pollination takes place. This can be caused not only from direct application of fertilizer to the plants, but run off from lawn and surrounding bed applications as well. Test your soil.
These are the most common reasons that holly shrubs will not produce fruit. I hope the list helps you find the cause of your plants not fruiting.
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