Q: My holly looks different than my
A: Your neighbor may have a different species. There are
approximately 175 species of holly in the world. These differ in
shape of leaves and size and shape of plant, among other attributes.
Only a few species are used commercially in the U. S. and Canada.
They are primarily English holly, (Ilex aquifolium), grown in
Washington, Oregon and British Columbia, and the Native American
holly (Ilex opaca) which grows along the Atlantic coast.
Q: What kinds of holly are found in the Pacific Northwest?
A: While several of the 175 species may be found in special
situations, commercial Northwest Holly Growers normally offer a
choice of variegated or green English holly. The variegated holly
has cream around the edges with green centers and the green holly is
a rich shiny green. Chinese(Ilex cornuta), and Japanese(Ilex crenata)
hollies- which are shrubs, not trees- are grown by commercial
nurseries for landscaping plants.
Q: What is the difference between variegated and English holly?
A: There is no difference. Variegated holly is just one variety of
Q. I have a beautiful green holly tree, but it has no berries.
A. There are several possibilities. One is that it is a male tree.
These have flowers, but do not set berries. The other is that it is
a female tree, but there are no males of the same species around to
pollinate it. Yet another is that the tree has a health problem
relating either to nutrients or pests.
Q. Are holly berries poisonous?
A. NO. Birds and animals count on holly to provide food during the
winter months. For humans, the berries will taste bitter and may
cause an upset stomach or act as a mild laxative, if enough are
ingested. While health benefits of holly are elusive, significant
health harms have not been documented. . On the contrary, it is a
perfect indoor decoration for people with allergies, as it contains
no dust, pollens, or fragrances.
Q. How can I use holly for decoration?
A. Use your imagination. Holly has survived for many centuries as a
festive icon. It has always been arranged in bowls, baskets or
vases. It is also used alone in wreaths or with other greenery.
Holly looks lovely with red carnations in February, with daffodils
in March, with tulips in May, and at Thanksgiving with pumpkins and
grapes. The combinations are endless, because it is so versatile.
Q. I am hearing some claims that holly is invasive. Is this true?
A. NO. The USDA National Invasive Species Information Center
considers invasive species as those that are non-native and which
harm the environment, the economy or human health. While English
holly (Ilex aquifolium) is non-native to North America, it is not
clear that it causes any harm to the environment. There are many
holly farmers who earn income from selling beautiful decorative
holly products throughout the country, which is a boon to the
Pacific Northwest economy. The claim of holly being invasive has no
basis in fact.
Q. Is this “tree of winter” a threat to our forests?
A. NO. Holly cannot thrive in our native forests because it is shade
intolerant and cannot compete in a dense forest environment.
Volunteer holly, seeded by birds, are almost always male trees that
will not reproduce. Holly is non-native to North America, but there
is no documentation that it will dominate our forests, such as
Himalayan blackberry and Scotch Broom have done in the Pacific
Q. When did holly first arrive in the Pacific Northwest?
A. Records show that English holly (Ilex aquifolium) was first
planted in 1874 in Portland, OR and in Puyallup, Washington in 1891.
Commercial sales from these trees began about 1898.
Q. I have been trying to grow some variegated holly from berries,
but they just don't seem to sprout. What am I doing wrong?
A. Berries from variegated English holly trees are sterile. The only
way to get new variegated trees is by propagation from cuttings.
Q. I am seeing dead leaves dropping off my holly tree. I thought
holly was evergreen so why are the leaves dropping?
A. After several years, old leaves drop off. If the tree has an
infestation of disease such as phytopthera (a fungus), leaves may
fall off prematurely.