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June - 2008 Questions &Answers Compiled by David Rodriguez County Extension Agent-Horticulture Bexar County

Special thanks to Forrest W. Appleton and volunteers of the "Master Gardener Hotline" in support of the weekly gardening questions and answers.

Question:
Mr. Rodriguez, I have two mature boxwoods in the front of my home that have been healthy for years and now in the last few months, have an area in the front of each plant that is brown and appears dead. The rest of the plant looks green and healthy. These spots are in a circle on each plant. Can you recommend anything I can use to correct the problem?
Answer:
Jim, boxwoods tend to do this and it seems to be associated with a root problem that affects individual limbs, sometimes after drought and sometimes after excessive rainfall. There is not much that can be done except to cut out those dead areas and let it fill back in.

Question:
I purchased a Possumhaw holly three years ago, a Warren's Red variety. I have not had any red berries yet. A local nurseryman told me I have a male plant that will never produce berries. They told me to buy a female and to plant it nearby so the female would have berries. My question is - will the male never produce berries? And, if I were to remove the male plant and replace it with a female Warren's Red plant would the female plant produce any berries with no male plant around? The information I get from the Aggie website indicated if you wanted a female with lots of berries you need to have a male nearby to cross pollinate it, but I didn't find any information on what berry production might be if no male was around.
Answer:
Male holly plants do not have berries. All Warren's Red Possumhaw are female plants so if yours is a male, it isn't a Warren's Red. Probably the best bet would be to buy another Warren's Red that has berries on it and replace the current plant. You should be able to transplant the current plant to another location in your landscape and it would then be the pollinator for the female. Without a pollinator, the female will not set fruit. However, this pollinator does not have to be a Possumhaw. Any holly that blooms at the same time will suffice.

Question:
I bought some pink loosestrife from a local nursery. Being unfamiliar with it, I went to the web to check it out. According to many sites, the plant is an ecological disaster. Even the variety I have (Morden's Pink) is considered dangerous due to cultivar mixing. Yet I find in on the TAMU list of Perennials for Texas. What's the story?
Answer:
Several of the loosestrife (Lythrum species) are considered invasive plants. However, those are only invasive in wet lands which I seriously doubt that you have. I wouldn't worry about it.

Question:
Our tomato plants are FULL of small square green flying bugs--leaf miners or?? Repeated spraying with Spinosad has no results. We think they are laying eggs in the tomato skin and thus ruining the fruit. What can we do?
Answer:
I feel sure that you have a stink bug infestation. They do not lay eggs in or on the tomatoes. What they do is insert their proboscis into the tomato, inject some chemical to break down the flesh and suck out the juice. This leaves the hard white spots under the skin. While it is disfiguring, it can be cut out or just eaten. Stink bugs are hard to control. One of the garden dusts such as sevin, endosulfan or permethrin should have some effect. Hand picking of the bugs is another option (but they are hard to catch).

Question:
David, I am originally from Minnesota and love lilacs. Are there any lilacs that are suitable for the Texas climate?
Answer:
Lilacs are suitable only for the most northern parts of Texas. With many native Texans and snow birds having the same desire as you, we have nicknamed the Vitex 'Texas Lilac' as a suitable substitute for the lilac. See the article at http://www.plantanswers.com/vitex.htm. Most nurseries carry this plant.

Question:
Mr. Rodriguez, the petals on my rose bushes do not fully open and they appear to have some type of rot on them. What is the problem?
Answer:
The most likely cause is a tiny insect called thrips. Cut one of the buds open and tap it on a piece of white paper. If you see tiny, slender insects crawling on the paper they are the culprit. They can be controlled with one of the insecticides containing acephate.

Question:
David, I live in Hollywood Park and my friend lives in Timberwood Park. We are both wondering if elephant ears are deer resistant compared to caladium. We both had the deer eat our caladium leaves and wonder if it is reasonable to put a pot of elephant ears where the deer roam.
Answer:
While I can give you no guarantee about what will happen in your yard, there are elephant ear plantings in Hollywood Park yards that are in areas of high deer traffic and do not seem to be even nibbled on.

Question:
What comes first, the squash fruit or the squash bloom?
Answer:
Squash, like all cucurbits, have both male and female flowers. The female flower will have a small fruit right behind it. If this female blossom is fertilized (pollinated) by the pollen from a male flower, it will mature as the fruit that we eat. If it is not pollinated, it will not grow any larger and rot on the vine. The male flower has no fruit behind it. Both male and female flower must open on the same day and pollinators, such as honey bees, must be present to transfer the pollen from the male flower to the female flower.

Question:
Mr. Rodriguez, I transplanted a Mt. Laurel from one plant bed to another about 2 weeks ago. I used a quick start solution and have been watering it daily but the leaves have all turned brown and are dropping off. The largest stalk is probably a half inch in diameter and the plant is probably 6 feet at his tallest. When I scratch the branches all the way to the top of the plant, the plant is still green. My question is will it survive or should I give up and save my time and water?
Answer:
The Texas Mountain Laurel does not respond well to transplanting, especially with the heat we have been receiving Even if it does survive, it has been set back so that you would probably be ahead by purchasing a small one which is growing in a container and replacing it.

Question:
David, can I grow gardenias in my area? When I have planted them through the years in central Texas, they have failed.
Answer:
Gardenias do not like the alkaline soil of the Central Texas gardens. If you must have them, then special conditions must be provided for them. They should receive morning sun and follow the guidance found in the article at http://www.plantanswers.com/forbidden_plants.htm.

Question:
Mr. Rodriguez, my fig tree is well over 25 yrs old. Each limb is about 4 inches round at the base and they are breaking off at the root?
Answer: Figs send up limbs from their roots over time. These limbs are often not very structurally sound and can break off quite easily in a wind storm or just from the weight of the vegetation. While you are losing some of your tree, I do not think that there is danger of losing the plant.

Question:
Why are labeled Harbor Dwarf Nandinas growing 6+ feet? And they have berries? They are all labeled and were purchased at different times and different places. Should I take out the tall growth? I purchased them for ground cover.
Answer:
The obvious answer has to be-they were mislabeled. If you take out the tall growth, more will just come back. I guess that you could cut the entire plant off at ground level and control its height in this manner. This would have to be done annually in early spring.

Question:
David, what type plants can a person plant to repel mosquitoes?
Answer:
There are no plants that will effectively repel insects. There is a scented geranium sold as Citronella Plant that might repel mosquitoes for a distance of a few inches but not enough to be of assistance.

Question:
David, can I spray a weed killer on Asian Jasmine to control Bermudagrass that was planted in early February?
Answer:
Once Asian Jasmine is established, you can spray it with just about any listed herbicide without damaging it. Since it is newly planted and actively growing, I would be careful of overspraying it with anything. If the plants are small and separated, you could protect them by covering them with something (such as buckets, cardboard boxes, milk jugs, etc.) that would prevent the herbicide from getting on the plants and spraying just the weeds.

Question:
Mr. Rodriguez, I planted some shrimp plants last year and they did great. This year they are bigger but the leaves are a light green color. The leaves look chewed on and they have no blooms. The other plants are doing well. What can I do to make these plants healthy again?
Answer:
If the shrimp plants froze to the ground (or you cut them back), the plants haven't had time to bloom. The light-green leaves indicate that they might appreciate fertilizer. Any good, high nitrogen (50%) slow-release fertilizer, such as 19-5-9, will work fine. Spread about a cup over the area of the bed and water in. The "munched on" look, in most neighborhoods this year, is caused by snails which have been out in abundance. Any of the Bug and Snail baits can be used to control them.

Question:
Mr. Rodriguez, we have about 15 Crape Myrtle trees. We noticed the leaves are cupping, and some of the lateral branches have a problem. The exterior bark is soft and can be easily peeled off on some of the lateral branches. Certain areas of the lateral branches that are affected are also a different color.
Answer:
If the upper surfaces of the leaves are sticky with "honeydew", the crape myrtles are probably infested with aphids. Any insecticide will control aphids. The crape myrtles exfoliate (shed) their bark each year. This is a natural feature of the crape myrtle and enhances its beauty.

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