QUESTION : We've just moved onto our own property
for the first time and I'm a very new gardener who wants
to make her yard very nice. Anyway, I need to know the average
last freeze date! I've looked all over the Internet and
I can't find any information.
ANSWER :This Aggie web site is a map of Texas with
the average last freeze date shown:
Remember that these are averages and that means that there
will be years when it will be before and some when it is
This map is part of The Texas Home Gardening Guide which
is found at this web site:
There you will find a lot of good information to help you
with your gardening
QUESTION : I have two Bougainvillaea vines, "Raspberry
Ice" which has a variegated leaf, and a standard one.
I keep them wintered in greenhouse space since they would
not survive our winter climate. I am interested in propagating
them but do not know how or when is the best way or time
of year. Someone told me it is not easy. Can I try the conventional
way by cutting off the tip of a branch, dipping it in hormone
mix and putting in soil and keeping it covered?
ANSWER :Bougainvillea can be propagated by hardwood
cuttings, softwood cuttings, layering and air layering.
Probably the most common way is softwood stem cuttings treated
with rooting compound and placed under mist. If you do not
have a misting system, covering with plastic to keep the
humidity high should work just as well.
This PLANTanswers web site on Asexual Propagation gives
QUESTION : We have had a disagreement over the nuts
found in the store that I have always called 'Brazil Nuts.'
Someone else said these are 'Butter Nuts.' Can you tell
me the difference between these nuts, and if they are both
available in Texas?
ANSWER :Brazil nuts usually refers to cashew nuts
which is a native of Brazil. Since this is strictly a tropical
plant, it would be rare for it to be grown in Texas except
possibly in the Lower Rio Grande Valley.
The Butternut is actually a type of walnut. It has the same
range as the eastern Black walnut except that it goes further
north as well.
So you are talking about a tropical nut vs. a hardy North
QUESTION : None of the landscapers or gardening
stores seem to know what can I use to take care of and control
a weed infested buffalo grass. Labels on the weed control
products do not mention buffalo grass and Im afraid of using
something that might damage and/or kill my grass. I was
told to use MSMA but that is only for a certain type of
weed and I have them all!!
ANSWER :MSMA or DSMA has been used by some to control
weeds and grass in Buffalo. It may cause browning in the
Buffalo but it will recover. If you have concern, you should
apply the herbicide to a small area and see what it does.
If you have nutsedge (nut grass) the herbicide Manage can
be used. You should use pre-emergence herbicides such as
Greenlight Portrait, Balan, or Betasan three times a season
(February, May and September) to prevent sprouting of weed
seed. Because Buffalo is a sparse-growing grass, there will
always be some weed problem.
QUESTION : I have many Euonymus kiautschovicus shrubs
in a hedge row, and they are heavily infested with Euonymus
scale. Some of the plants are defoliating at the tops, and
most of them are defoliating at the bottoms (still quite
a bit of green left). Is it possible to use rejuvenate pruning
techniques on this shrub? Can I cut these shrubs just above
the ground to encourage new growth and what would be the
best time to do this?
ANSWER :This PLANTanswers web site on pruning is
an excellent article:
This is what it says about rejuvenating broad-leafed evergreen
hedges: "When these plants become old and straggly,
cut them back 6 to 8 inches from the ground before spring
growth begins. Don't cut them back too early, however, because
a flush of growth could freeze and set them back. Prune
only after the danger of the last killing frost is past.
Such pruning stimulates the growth of new shoots from the
base of the plant. Many gardeners prefer to remove only
about one-third of the branches at one time and retain the
general contour of the plant. This method also can be used.
In the long run, probably the best thing to do with overgrown
broad-leaved evergreens is to remove and replace them."
I am reluctant to recommend the rejuvenation by pruning
though and feel that the last sentence above about replacement
may be the best solution. While the Euonymus kiautschovica
is supposedly the least susceptible to scale of the evergreen
Euonymus, you have seen how devastating the scale problem
can be. I am afraid that even if you eliminate the scale
through pruning and treatment, it is just a matter of time
until they return. If you choose to treat them, the use
of a horticultural oil is probably the most effective solution.
QUESTION : I am a Landscape Architect in Cambridge,
MA. One of my clients, in Texas, has a number of Pecan trees
on his property. He is interested in flooding the landscape
but salvaging the trees. He was told that there was a way
to flood the trees incrementally, and I was wondering if
you have any information on the subject.
ANSWER :There is nothing wrong with flooding pecan
trees as long as the water does not stand around them for
longer than 24 hours. In other words we want to put the
water on and then we want it to drain away. If the water
stays longer then that, it will eventually weaken and kill
the trees. When we flood irrigate, we try to water at least
every 3 weeks.
QUESTION : Why doesn't my wisteria bloom?
ANSWER :Youth could be the problem since seedling
plants require several years to flower and sometimes fail
to flower at all. Grafted plants, the kind purchased at
nurseries and garden centers, should not have this problem.
Reluctance of wisteria to bloom abundantly is usually due
to a lack of one or more of the following cultural requirements:
full sun, good drainage, and light fertilization in the
fall, not spring. Another essential is annual pruning, which
can be done by shortening new shoots to five buds in summer.
If a grafted or cutting-grown Chinese wisteria refuses to
flower in three or four years after planting, or a Japanese
wisteria is barren after about seven years, prune it heavily
and fertilize with superphosphate. If this fails to produce
blooms root-prune by driving a spade into the soil 24 inches
from the trunk around the plant.
This web site contains information on the blue passion
flower (Passiflora caerulea). I don't know if this is the
variety you have or not as there are many. However, the
culture is basically the same for all with the basic difference
being in their hardiness:
This is a portion of what it says: HOW TO GROW. As house
plants, passion flowers grow best with four hours or more
of direct sunlight a day and night temperatures of 55 degrees
F. to 65 degrees F. and day temperatures of 68 degrees F.
or higher. Plant in commercial potting soil and provide
a climbing support. Keep the soil evenly moist. Feed the
vine every two weeks with an all-purpose fertilizer applied
at half the strength recommended on the label. When growth
slows in the fall, stop fertilizing and let the soil dry
slightly between waterings until new growth starts. In January
cut the plants back to 6 inches to force new growth.
Outdoors, most passion flowers are hardy in Zones 9 and
10. Hardy to Zone 5 with protection, wild passion flower
loses its leaves in colder regions, but is evergreen farther
south. Plant passion flowers in full sun near a support.
They will grow best in a deep, moist, well-drained sandy
loam that has been enriched with compost or leaf mold. Prune
the vines heavily in fall or early spring to remove deadwood
and to control rampant growth. Propagate additional plants
from cuttings 4 to 6 inches long, taken at any time during
active growth. Germination of seed is slow and uncertain.
If your's is growing in the full sun in deep well-drained
moist soil and its roots are mulched and it still doesn't
bloom, I would probably remove it and put in something else.
QUESTION : I live in Blanco county, in the hill
county. For a number of years I've tried growing various
lettuces in fall, winter and spring gardens - they look
beautiful - but are so bitter, they are inedible. I've assumed
it is due to the alkaline soil, I've been composting heavily
for four years now (manures, hay, oak leaves) and I still
can't grow a tasty salad.
ANSWER :There are basically three things that can
cause lettuce to be bitter; low soil fertility, low soil
moisture and high temperatures. This is the reason that
fall planted lettuce usually does best in our part of the
country. The leaf lettuces do fine but the heading varieties
do not. Lettuce can withstand frost and light freezes, but
if the temperature is to drop below the mid 20's, it should
In addition to the organic material you are using, about
2 pounds of any good fertilizer per 100 square feet (1 Tablespoon
per square foot) should be added and apply water before
the top inch of soil becomes dry.
Variety selection is also important. Salad Bowl, Black-Seeded
Simpson, Ruby and Red Sails all are fine.
QUESTION : Four years ago I bought a grapefruit
tree. The first year, I had 4 medium-sized fruits from the
tree. Over the winter the temperature dropped below freezing
and the tree apparently died. In the spring I planned on
digging it up and replacing it. However, I noticed part
of the trunk was still green so I left it to see what would
happen. The grapefruit tree is now almost 10 feet tall,
but it has yet to produce any fruit. What do I need to do,
if anything to get fruit? Do I need to re-graft the tree?
Will it ever produce again?
ANSWER :Even though the freeze did not kill the tree,
it did kill the budded portion of the tree which produced
the grapefruit. Most trees are budded onto a specific rootstock
which performs better than a tree on its own roots. So all
you have left is rootstock which may or not produce desirable
fruit. You could re-bud the tree using the t-bud method.
This procedure is outlined at the following Plantanswers
All you need is wood from a tree which produces desirable