DEER PROBLEMS AND DEER RESISTANT PLANTS
by Jerry Parsons, Ph.D.
Horticulture Specialist, Texas Agricultural Extension Service
in San Antonio
When plants start growing, pests start "pesting".
I have at times discussed some of the easier-to-control pests
such as spider mites, loopers, worms, aphids and squash bugs.
However, these pests are insignificant when confronted with
the truly destructive garden beast-of-eat known as deer.
How much can a cute little Bambi-type deer
eat? Too much! To calculate how much a deer can eat, use the
energy content of an average apple tree twig. Animals get
energy from the food they eat, and all animals need energy
to perform such simple life-functions as walking, running,
or even breathing.
For example, a doe that weights about 130 pounds
in winter requires 2500 calories per day. To meet its energy
needs, the doe must eat at least 2800 twigs a day. Each twig
is about 4 inches long and weighs about half a gram (dry weight).
If a young tree has 20 twigs on it, one animal
can wipe out 140 trees a day. A group of deer can mean the
loss of 2800 trees. If these animals eat the twigs for 30
days, the number of trees that could be affected would 84,000.
How can you deter these ravaging beasts? A
tall, expensive fence has been the answer for most ranchers
in Texas. If you find a deer that can jump a ten?foot wire
barrier, you can enter it in the next Olympics. However, such
a barrier is expensive. An inexpensive, movable fence is described
at this website:
You may want to try repellents. High cost,
limitations on use, and varying effectiveness make most repellents
impractical. The effectiveness of repellents will depend on
several factors. Rainfall will dissipate some repellents,
so reapplication will be necessary after a rain. But some
repellents do not weather well even in the absence of rainfall.
A deer's hunger and the availability of other, more palatable
food will have a great effect on success. In times of food
stress, deer are likely to ignore either taste or scent repellents.
A pepper-based repellent is described in the website address
Much has been written and said about what the
serious gardener can do to lessen the impact of deer in the
landscape. This usually includes a list of plants that deer
are not supposed to like --- such as the one previously used
by the Texas Extension Service at:
Some folks enduring huge populations of deer
have found these lists and proclamations to be of little value
to the gardener who is trying to put some variety into a landscape
and do his share to improve the beauty of his surroundings.
At this website:
Forrest Appleton has listed plants that, through
trial and error, he has found to be the least bothered by
As if eating plants and shrubs was not bad
enough, those silly deer also kill just about as many plants
with their inappropriate "stomping" and rubbing.
The physical damage caused by deer by means other that grazing
is something that is seldom addressed by those who would have
us believe that the deer are a definite plus in our communities.
No small tree or shrub is safe from the buck that is rubbing
the velvet from his antlers or marking his area. They not
only cause breakage, but they will rub the bark completely
off a plant, girdling it and causing its eventual death. The
only effective protection is to place an unsightly cage of
fencing or concrete reinforcing mesh around the plant. If
you install small plants, this means a lengthy period of eyesores
in the landscape.
Realizing that few plants have the ability
to resist munching by hungry deer, and fewer yet have the
ability to thrive in shady locations, you can imagine how
VERY FEW plants can be described as:
Semi-Shade Tolerant Plants-Of-Color Which Deer
Do Not Prefer to Eat But Can Damage
With the Rubbing of Antlers and the
Stomping of Hoofs
(Translation: These plants do well in semi-shade and deer
normally won't eat, but can damage with antlers and hoofs)
PS: The creators of this list also wish to emphasize that
the more sun these plants receive, the more flowers will be
produced and the less "spindly" the plants will
BRUGMANSIA syn. Datura
(See Photos at: http://www.plantanswers.com/angel_trumpet.htm)
Desperate times and seemingly impossible situations
call for drastic solutions. Gardeners in many parts of South
Texas are "desperate" for plants which will grow
and hopefully bloom in the shade. Plus, they want plants which
the deer won't eat.
Deer won't each plants which are distasteful
to them. Most toxic plants are distasteful. Therefore, gardeners
should select plants that are labeled "poisonous".
The term "poisonous" means that if enough (usually
larger quantities than can be stomached or consumed because
of distasteful attributes) of the plant and/or plant parts
are eaten, the animal will become ill and possibly die.
As a rule, animals and children are usually
repelled by the nasty-tasting "poisonous" plant
after the first bite. Some of the plants with this "built-in"
protection from animals are lantana and oleander. Another
plant which uses this defense mechanism and is on the verge
of becoming a Texas favorite has an angelic name-- Angel Trumpet.
The Angel Trumpet is in the Brugmansia genus. Angel Trumpet
is a Datura-type plant but with the added advantage of not
producing the poisonous seed common with other Datura. However,
all of the Angel Trumpet-foliage and bloom are poisonous if
enough is ingested. But, the taste is repulsive to deer, will
grow and bloom in semi-shaded areas, and emits a wonderful,
Angelic scent at sundown and into the evening hours while
you are enjoying the cooling nighttime temperatures. It is
a "dream-come-true" plant for Texas. It gets its
name from the large, long, trumpet?shaped flowers that are
abundant and fragrant.
While Brugmansias are still often found under
the name Datura, the true Datura are short-lived, herbaceous
plants with smaller, more upright flowers and capsular fruits
that are usually prickly and contain very poisonous seed.
The Angel's Trumpet is root-hardy (freeze to the ground most
years but sprout again from the roots in the spring) in most
areas of Texas, except in extreme north Texas. There are currently
five or more Brugmansia species, most originating in the Andes
of northern South America. They are evergreen, or semi- evergreen,
and their leaves are large and soft, rather like tobacco leaves
but smaller. All parts of the plant are narcotic and poisonous.
Remember, it is the dose that makes the poison! Some plants
considered "poisonous" are narcotic or hallucinogenic
if used in the correct "dosage". For example, Mountain
Laurel berries are deadly if chewed, but were used to make
a mescal?like drink by Indians who knew the safe "recipe-for-happiness".
The plants prefer a warm to hot climate and
a light, fertile, wel-?drained soil. They are best grown as
small trees. They can be shaped when young to obtain a single
trunk or can be kept trimmed as dense, rounded shrubs. Keep
well watered during the growing season.
Whitefly and red spider mite populations should
be controlled as needed.
The 'Charles Grimaldi' Angel Trumpet is named for a California
landscape designer. This 6-ft. tall hybrid cultivar ('Dr.
Seuss' X 'Frosty Pink') has very large, pendulous, fragrant,
pinkish yellow to salmon pink flowers, blooming mainly from
autumn to spring. It has very large leaves and, with age,
will form quite a thicket of stems.
BUSH MORNING GLORY
Ipomoea fistulosa Mart. ex Choisy
Find photos of the Bush Morning Glory at this
This interesting plant is in the sweet potato
family (Ipomoea) and has a shrub-like growth habit. The scientific
name is Ipomoea fistulosa. It grows in very dry places and
can be considered a xeriscape plant. The bush morning glory
is the most prolific bloomers of any of the summer perennials.
The plant is covered with medium-size, light
pink (there is a white form available) blooms all summer.
Blooms last only one day but clusters of blooms are formed
in the axil of every leaf. Plants can get 6-8 feet tall with
multiple trunks. When hard frosts kill plants, the tops should
be removed. In South central Texas, plants will sprout again
from the hardy root system the following May. Once established,
the bush morning glory is a tough plant, meaning it is both
drought-tolerant and heat-tolerant. It blooms best in direct
sun and will not bloom as well if it gets less than 8-10 hours
of direct sun. Plants can be cut back monthly to encourage
branching and increase the blooming surface. Cutting back
in July will reduce plant height and encourage a spectacular
In India, writings describe: "It is not
eaten by livestock (ducks, goats, cattle, buffalo, elephants,
etc.) and is easily propagated by stem cuttings and withstands
periods of flooding and desiccation. It makes an ideal living
fence and is easier to manage than the common alternatives:
upright cacti succulent Euphorbias or thorny species of Acacia
and Prosopis. Under dry conditions it does not seem capable
of tolerating much competition but in water or mud it is highly
competitive. Under wet conditions the stems become inflated
and may be as thick as a human arm. These inflated stems are
hard and not spongy as one might expect. Also they are capable
of rooting. In regions that are regularly flooded Ipomoea
fistulosa is often dominant and forms stands of several hectares."
In other words, this plant is tough and beautiful
in water and in drought and the deer don't prefer it!!
Bush Morning Glory Seeds are available by sending
a stamped, self?addressed envelop with a check for $5 made
payable to Dee Emory:
13655 Prince's Knoll
San Antonio, Texas 78231
More Shade Tolerant, Deer-Resistant Plants
(Michaelmas Daisy)(Aster spp.)
photos at: http://www.plantanswers.com/four_clock.htm
The attributes of an old-fashioned plant named
Four o'clock have become more important because of the changing
environmental adversities that have been experienced by the
Texas gardening public. Texas gardeners desperately need a
(1) will flourish in periods of severe drought
and water restrictions. These are listed among the most drough-tolerant
: Cockscomb, Coreopsis, Cosmos, Four o'clock, Moss Rose, Petunia,
Purslane, Verbena, Zinnia
(2) will bloom in less than full sunlight situations.
These are listed among the most shade or semi-shade tolerant:
Begonia, Bellflower, Coleus, Dwarf Lobelia, Four O'Clock,
Flowering Tobacco, Impatiens
(3) is deer and rabbit tolerant in that it
is not a preferred plant for deer and can recoup rapidly after
being damaged by deer, dogs, and other varmints
(4) is fragrant,
(5) is a long-lived tuberous perennial and
(6) is one of a very few hummingbird and butterfly
plants for shady growing conditions.
The skeptics may wonder why this wonderful
plant has not been promoted before now. The simple answer
is that this plant is so adapted and tenacious, it is sometimes
considered invasive. This may be a case of one person's trash
is another person's treasure, OR familiarity breeds discontent.
Maybe it is because the flowers do not stay open all day.
The flowers are not responding to an internal clock but to
temperature. The flowers open in the afternoon, about 4 o'clock.
Usually, the flowers close the following morning, but if the
day is cool, they will stay open until the new flowers open.
In the Hellish summer temperatures of Texas, folks can only
enjoy their flowers in the late evening anyway, and four o'clock
provide beauty and fragrance during that cooler time of the
Flowers are trumpet-shaped, with the throat
as much as 2 inches long and 1 inch wide with five lobes.
Flowers are produced in shades of white, yellow and about
every shade of pink imaginable. The striped flowers appear
to be infected with a virus disease that creates the interesting
patterns. The flower is an enigma in that it completely lacks
petals. The showy portion of the flower is actually an outgrowth
of the sepal, which in most plants is green and leaf-like.
The small, leafy structure from which the flower
emerges is made of bracts formed from modified leaves. The
absence of petals is rare in the plant kingdom. Each flower
that is pollinated produces a pea-size black "seed."
The seed is not really a seed but a fruit. A true seed is
produced inside something --for example, inside a pea pod
or the capsule of a petunia. In this case, each flower produces
one seed that is enclosed inside the ovary. So, in reality
the "seed" is a "fruit."
Former Bexar County Extension Horticulturist
Greg Grant writes in his Arcadia Archives section of PlantAnswers.com
that he dug the root of a Four O'Clock that he found in a
little abandoned yard that was dark hot pink in color and
grew it for a year before he realized it had NO fragrance.
Greg's granny's plant had blooms that had a fragrance as sweet
as sugar! Greg has provided us with a fragrant yellow-blooming
plant from his Granny Ruth.
The Four o'clock name is a misnomer. The name
Mirabilis was given by Linnaeus in the middle 18th Century
and shortened from the Latin word "Admirabilis"
which gives us "admirable" and is a reference to
the showy flowers. The name "jalapa" is due to botanical
confusion. The fleshy roots of this plant were thought to
be the source of "jalapa," a drug that was used
in Central and South America as a laxative. In reality, the
jalapa was from a member of the morning glory family. The
common name -- Four O'clock --is one of our oldest garden
flowers and was originally shipped back to Europe by the Spanish
conquistadors. The flowers are fragrant and produce a subtle
and delightful fragrance during the early evening hours when
the wind is not blowing. Hummingbirds and lunar moths both
seem to like to visit the flower for the abundance of nectar.
The Four o'clock -- also know as Belle De Nuit
Blanche, Belle De Nuit Rose, Belle De Nuit, Buenas Tardes,
Dondiego De Noche, Gecesefase, Geje Safa, Gulabbas, Heft Reng,
Jalap, Lala A'Bbas, Maravilla, Noche Buena, Tzu Mo Li, Bunga
pukul empat, Kederat, Kembang pagi sore, Kembang pukul, Nodja,
Segerat, Ubat jerawat --also has the medicinal uses and properties
of antifungal, antimicrobial, antiviral, antibacterial, diuretic,
alterative, carminative, cathartic, hydragogue, purgative,
stomachic, tonic and vermifuge.
The phytochemicals it contains are:
Its ethno-botanical uses are: abscess, alterative,
boil, bruise, carbuncle, carminative, cathartic, colic, cosmetic,
diabetes, diuretic, dropsy, gonorrhea, hepatitis, herpes,
hydragogue, hypochondria, itch, liver, pimple, purgative,
rash, repellant (insect), sore, splenitis, stomachic, strain,
tonic, tumor, urticaria, uterosis, vermifuge and wound.
Gold Star Esperanza
See photos at:
Tecoma stans 'Gold Star' Esperanza (Yellow Bells,
Yellow Alder) is a heat and sun loving tropical with golden-yellow
bell shaped flowers from late spring till frost. Zone 9.
Exposure: Full sun is best but will tolerate
Size: Three to four feet as an annual.
Blooms: Lightly fragrant, golden yellow, spring till frost.
Uses: Container, specimen, bedding, xeriscape, etc.
Notes: Remove seedpods to promote faster re-bloom. Texas native.
'Gold Star' Esperanza is a selection Greg Grant
made from a private garden in San Antonio. It was introduced
by Lone Star Growers. 'Gold Star' was selected because it
was the earliest blooming Tecoma stans that I had in trial.
Previously, Esperanza was difficult to sell to gardening consumers
because it didn't produce blooms in the container until late
in the season. 'Gold Star' actually produced them as a liner.
Tecoma stans requires bright light and warm temperatures.
This particular selection is intermediate between the West
Texas Tecoma stans angustata and the tropical Tecoma stans
stans. Flower and leaf size is intermediate between the two.
Although grown as a shrub and a perennial in
San Antonio, South Texas, and Mexico, Esperanza works best
in the nursery trade as a tropical container plant, similar
to Hibiscus, Bougainvillea, and Mandevilla. It is generally
sold in one gallon or three gallon containers.
Esperanza has relatively few pests. In the
greenhouse, it can be attacked by spider mites and aphids.
Outdoors it is generally pest free. To keep the plants tidy
and continuously blooming in the landscape, it is recommended
that the clusters of seed pods ("green beans") be
Excellent heat tolerant selection BUT should NEVER be transplanted
where sprinkler irrigation is used, AND should NEVER be transplanted
before June 1 (July 1 is safer!) Mulching is HIGHLY recommended!
See photos at: http://www.plantanswers.com/turkscap.htm
Turk's Cap (Malvaviscus arboreus) is a shade-tolerant,
deer-resistant Texas native that has blooms which hummingbirds
love. It grows in sun or part sun to heights of 4 to 5 feet,
forming a shrub-like perennial plant. It flowers from late
spring through fall, with bright red petals rolled loosely
around the flowers' reproductive parts. It is a relative of
the hibiscus, and its variegated green?and?white foliage make
a perfect compliment to colorful flowers. It is a showy stand?out
in shady areas where the green color is lost.
Hummingbirds love it and enjoy feeding in the
shade. Often, it dies to the ground in winter, then comes
back in the spring. It is a root-hardy perennial that is an
old-time favorite of early Texas gardeners since it is deer
resistant as well. It is drought tolerant and some have indicated
that plants can be weeded with a glyphosate herbicide such
as Roundup, Kleanup or Finale without significant, if any,
damage to the foliage of the Turk's Cap. (However, try at
your own risk!!)