QUESTION: We would appreciate your recommendation
on which type of grass to use around our new swimming pool.
The natural soil in the area is 2 to 6 inches of heavy black
soil over SOLID caliche/rock. It currently supports natives
such as cedars, mesquite, horseherb, bluebonnets, spiderwort,
etc. We intend to backfill/top dress around the pool area
(approx 2000 sq ft) with a minimum of 4 inches of high?quality
topsoil (GardenVille's "4-way mix"). The pool
area will have a very natural, native look ? not manicured.
We intend to use sod, not seed or plugs. The area will be
maintained "organically" ? we do not use pesticides/herbicides.
Would zoysia, buffalo, or some other grass be best? Also,
can I "seed over" these grasses with wildflower
seeds or will one compete with the other?
ANSWER: I assume that the area you intend to sod
with turf is in the full sun. If so, I recommend that one
of the wide bladed zoysias (El Toro or JaMur) be used. These
zoysias can be maintained using a regular rotary mower.
Zoysia does not lend itself to overseeding. Buffalo grass
would. However, buffalo will not withstand the foot traffic
that you will have around the pool. And since it is ideal
for overseeding with wildflowers, it will have constant
weed problems the rest of the year.
QUESTION: We have recently moved into a house with
several rose bushes, including a large miniature rosebush.
When should these be trimmed back, they are growing tall,
but not filling out. We do not know how to care for them,
but want to learn. Also, there are 2 large camellia bushes.
Neighbors want starts from these--how is that done?
ANSWER: Check out this PLANTanswers web site for
just about everything you need to know on roses:
Camellias can be propagated by cuttings taken in mid?summer
when the new growth is slightly matured. Rooting hormones
should be used and the cuttings will root best under mist.
See this University of Georgia web site for information
on shrub propagation:
QUESTION: I have been told that there is one plant
that is the "true" Yellow Rose of Texas. Could
you tell me if this is so and if they are available for
purchase at nurseries? If not, what yellow rose would you
recommend that requires a minimum of care (suitable for
planting at a cemetery)?
ANSWER: 'Harrison's Yellow" is considered by
some historians to be the 'Yellow Rose of Texas' but as
you will see from the article at the below URL, this rose
does not do well in Texas where the growth season is long
and summer temperatures are high. This article also discusses
the legend of the Yellow Rose of Texas, Emily West, who
was immortalized in the folksong by the same name.
Another yellow rose that you might consider for your planting
is "Mrs. Dudley Cross". This is what Dr. William
C. Welch says about it in his book, Perennial Garden Color.
"This is a favorite of Tea rose connoisseurs. The full,
pale yellow flowers are usually tinged with pink. The stems
are thornless or nearly so and the foliage is exceptionally
healthy and disease resistant. Color and flower shape are
somewhat similar to the more modern 'Peace' rose but 'Mrs.
Dudley Cross is smaller and daintier in size. This is one
of the Tea roses most often found thriving in old or abandoned
gardens. The flowers are excellent for cutting."
QUESTION: I have a 9- year-old water oak that is
about 7.5 inches in diameter. About a month ago, sap started
running from a spot about 2 feet above the ground. I took
a picture to a local nursery and had a tree service come
out and look at it. Both thought that I had a borer in that
spot. They recommended that I attempt to push a wire through
its tunnel and kill the borer and spray the tree with lindane.
As I attempted to find the hole, I used a knife and removed
a thin layer of bark about 2.5 inches long by 1" wide
down to a layer reddish brown in color. I did not find a
hole indicating a borer. However, in the middle of the area
where I removed the outer bark, I could see an area about
3/8 inch in diameter running sap. This is in the same spot
where the sap was running through the outer bark. What should
I do next? Could this be life threatening to the tree?
ANSWER: What you describe sounds like wetwood. In the TAEX
Texas Plant Diseases Handbook , found at this Aggie web
and looking under the section on trees we find this information:
Wetwood (bacterium ? Erwinia nimipressuralis): Affected
trees exhibit a sap flow from crotches. The bark below the
crotch has a water soaked appearance. The sap flow is the
result of bacterial by?products producing abnormally high
pressures within the vascular system. For more information
on wetwood and its control, refer to the section on elms.
Wet wood or Slime Flux (bacterium ? Erwinia nimipressuralis):
Chronic bleeding of sap from crotches, wound or other weakened
areas of trunk, with unsightly discoloration of bark in
affected area. Sap frequently is sour smelling. Bleeding
or fluxing is most pronounced during spring months or during
wet weather. The problem results from fermentation processes
of the causal bacteria creating pressures up to 60 pounds
per square inch within the tree. Tapping directly into the
trunk just below the affected area to provide an outlet
for abnormal sap and gasses will relieve internal pressure
and may aid in recovery. Drill a small hole (one?half inch
diameter or less) directly below the bleeding site and slightly
upward into the center of the trunk. Install a tight fitting
drainpipe in the drilled hole making sure the end of pipe
extends far enough outward so that sap does not fall on
QUESTION: I have two mature Magnolia trees one in
the front yard, one in back. They both have droopy under
curled leaves with brown spots on the top-side of the leaves
and black spots on the bottom side. Most of the leaves seem
to have the spots. There are some yellow and some brown
leaves on the trees and a large number of leaves on the
ground. I talked to a local nursery woman about 6 weeks
ago and showed her the leaves. She suggested that I water
the trees at the drip-line about 15 minutes a day. I have
done this, not everyday but reasonably regularly. The trees
are in a lot worse condition than they were when I consulted
the nursery woman. HELP!
ANSWER: There are a number of fungal leaf spot diseases
that magnolias are subject to getting. They rarely cause
severe damage and require no control. It is common for magnolias
to lose a large amount of leaves this time of the year (and
in fact they may lose all) but they will quickly replace
them. See this Michigan State University Extension web site:
(Magnolia Disease Problems)
Magnolias are also subject to a bacterial blight. See this
Oregon State University web site for a description and an
image of this disease:
I recommend that, if there is one available locally, you
contact an arborist for his opinion and recommendations.
You may also contact your local county extension agent.
QUESTION: We are already having a massive invasion
of snails and slugs. Using a metaldehyde type of product
with bait that works fairly well. In the back yard we have
a dog and can't use this type of product and keep our dog
healthy. We are using Diatomaceous earth. It is better than
nothing, but not very good. Is there a better product for
the back yard and is there any special technique for applying
it? Also is there a better product for the non-dog areas?
ANSWER: You are dealing with one of the most frustrating
pest problems, and I'm afraid I don't have a magic bullet.
You are correct in exercising care with metaldehyde baits
around your dog. Dogs, for some reason, are exceptionally
susceptible to metaldehyde and, I am told, seem to be attracted
to the bait formulations. Check out the suggestions below;
I am interested in any feedback you might have.
Snails and Slugs
Snails and slugs are one of the gardener's biggest challenges.
They require a truly integrated control approach, using
several different tactics.
(1) Baits. Metadehyde baits kill slugs better than any
other pesticide available to homeowners. Although baits
will not completely eliminate these pests, they are an important
control tool. When used properly, metaldehyde baits should
pose limited risk to dogs or other pets, wildlife, etc.
However care should be taken to avoid placing baits in such
a manner that dogs (especially) can reach significant quantities.
To enhance effectiveness of baits, use during periods of
dry weather and turn off the sprinkler systems for a few
(3?4) days after application. Metaldehyde acts by causing
intense irritation of the slug when it is either ingested
or contacted. The slug responds to the metaldehyde irritation
by producing a large amount of slimy mucous. Ultimately,
the slug dies from loss of moisture.
Tips for keeping baits out of the reach of pets include:
** When using baits, scatter them lightly over the infested
area, rather than leaving it in piles. This should reduce
the attractiveness of the bait to dogs, and make it unlikely
that the pet could eat a toxic amount of the product. The
best place to put baits is directly between snail hiding
places and their food.
** Place metaldehyde baits in locations where the dog cannot
reach (e.g., in the cracks and crevices where snails and
slugs hide during the day, behind prickly shrubs where the
dog will not go, underneath decks, or under shelters you
** Liquid bait formulations tend to last longer outdoors
and may be less attractive to dogs [Feedback here would
be valuable]. Deadline is one brand.
(2) Eliminate as many snail and slug hiding places as possible.
Tamp down soil around edging and next to house (crevices
where many slugs and snails hide); fill in spaces amongst
masonry or stones with cement; fill in holes in trees with
cement or expanding foam; store firewood off of ground;
remove unnecessary boards, stones, weeds, ground cover,
(3) Because snails and slugs are relatively long?lived,
and do not reproduce quickly, intensive hand picking can
be effective. Place boards, rolled up newspapers, or fruit
rinds on the ground for slugs and snails to hide under,
then pick the pests off and destroy. Search for snails and
slugs at night or on rainy, overcast days. A week or so
of intensive handpicking should have a significant impact
on slug numbers.
(4)An alternative slug killer is household ammonia. A 5%
solution (1 part ammonia to 19 parts water) is reported
to be a highly effective contact killer for slugs (probably
not as effective for snails because of their protective
shell). Spray the slugs directly at night or when they are
active. You must contact the slug directly with the spray.
Beer traps will effectively catch snails and slugs. Sink
shallow bowl or dish (old margarine tubs work well) into
the ground and pour an inch or so of beer into the bottom.
The beer has to be deep enough to drown the slugs. I am
also TOLD that Budweiser and Michelob brands work best
Sugar water with a bit of yeast added also works.
(6) Nailing a strip of copper around raised bed gardens
provides an effective repellent. This assumes you don't
already have slugs in the raised beds. Others have reported
success using 2 to 3- foot barriers of sawdust to keep slugs
out of sensitive sites.
Extension Urban Entomologist
Texas A&M Research & Extension Ctr.
17360 Coit Rd.
Dallas, TX 75252?6599
QUESTION: I am building a small garden 8'x 8'. It
is above ground, about 16 inches tall. What mix of soil
will be best suited for peppers?
ANSWER: If you are going to use the native soil
that you have, then you should condition it with a goodly
amount of coarse sand and a lot of organic material such
as compost. In the 16 inches, you should have about 6 inches
of your clay, 4 inches of sand and 6 inches of compost.
If you are buying and bringing in soil, look around for
a supplier that sells garden mixes and see if they have
one composed of soil, sand and compost. It should be similar
to the above description. You will need a little over 3
cubic yards for your project.
Which ever you choose, you need to remember that each year
you will need to replenish the organic material, adding
enough to bring the soil back to its original level.
QUESTION: We recently built a home in a subdivision
in southwest Austin. This is the first time I've gotten
to garden in Texas, I'm originally from Pennsylvania. I'm
puzzled about how to prepare the ground for planting? You
see, about 6 inches under the weedy topsoil is solid limestone
? ledges of it. I start digging in various places and keep
hitting rock. I've dug out boulders (6' x 4' x 2') and smaller
rocks but by the time I get down deep enough to remove the
rock I'm 2-feet or more below the top soil. (Raised beds
seem out of the question at this time because of neighborhood
restrictions and easements.) Some of the boulders are so
huge I can't move them. How can I plant trees and shrubs
when I can't even get 6 inches down let alone the depth
of the pot? (I really need to screen a view along the back
fence with some shrubs but can't get to the soil.) I've
bought several native Texas plant books and considered myself
a good Pennsylvania gardener but I'm totally at a loss on
how to handle this! Any advice-- short of moving?
ANSWER: Welcome to the challenges of gardening in
the Texas Hill Country. If you cannot dig a hole sufficiently
large enough to plant your transplants, the only 2 answers
are to try another location or construct a raised bed. The
main problem with chipping out holes in the limestone (other
than the fact that there is no soil) is drainage. If you
do get a hole large enough to accept your transplant, fill
it with water and see how long it takes for the water to
soak into the soil. All water should drain from the hole
in about 24 hours or less.
You might go to your library or favorite bookstore and
check out this book:
Gardening Success With Difficult Soils : Limestone, Alkaline
Clay, and Caliche by Scott Ogden; Taylor Pub; ISBN: 0878337415