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

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

Question:
David, my Bermuda front yard needs to be re-seeded because there are some bare spots. Can I take advantage of the recent rain to re-seed my yard this weekend (Early May)? If so, can you please show me how to re-seed the Bermuda lawn?
Answer:
Now is the time to plant Bermuda seed, one pound will cover about 200 square feet. Also buy some play box sand. You need to mix the seed with enough sand to lightly cover the area you wish to seed. The reason for the sand is so that you can see where you have spread the seed. The seed are so small that you cannot see them. After seeding, you need to lightly water the area and continue to do this at least once a day until you see you have a good stand of Bermuda. About 3 weeks after you see the first sprigs, you should be able to quit watering daily and then water deeply once a week.

Question:
Mr. Rodriguez, I have about 500 sq. ft. of established Asian Jasmine in my front yard. I have about 800 sq. ft. of partially shaded area in my back yard that I want to cover with Asian Jasmine. I would like to propagate the front yard Asian Jasmine into 500-800 Asian Jasmine plants that can be planted in the back yard area. What is the best method for propagating these plants?
Answer:
I would suggest that you take 12 inch by 12 inch squares out of your established planting. Use a sharp-shooter shovel and dig about a 3-5 inch root section with the foot square section -- much of the top growth can be removed for convenience but leave as much as possible. Leave a 12 inch section undisturbed on all sides of the section to be removed and fill in holes from which sections were removed with sand. Plug the back bed with the foot sections of Asian Jasmine and fertilize -water the planting from which the sections were removed. Both should cover and recover rapidly.

Question:
Dave, when is the best time to plant blackberries and raspberries?
Answer:
The best time to plant berries is in January and/or February. Blackberries are best started from root cuttings, but you will need plants to establish raspberries. The best blackberries for your area are Brazos, Rosborough, and Shawnee. There are two thornless blackberry selections you may want to try, Navajo and Arapho. The only raspberry which will survive in your area is Dorman Red. Although it does not have the quality that the northern raspberries have, it is a raspberry which will grow in the south. The only significant problem you may encounter on these berry types is iron chlorosis caused by high pH soils. You will probably need to apply iron chelates if your soil pH is above 7.5.

Question:
Dave, I am having trouble with snails and pill bugs eating my seedlings and young plants. How can I control them?
Answer:
Use one of the products sold as Snail and Bug Bait. You can find this in most garden centers/nurseries. I find the granular ones to work best. Just sprinkle a small amount of this around the plants in accordance with the label instructions.

Question:
David, why is it hard for plants or turf to thrive under an oak tree?
Answer:
There are two main problems - light and moisture. Oak trees have vast, shallow root systems that will consume most of the moisture that is applied there (by you or by rainfall) and they create shade which limits the choice of plants that will grow there.

Question:
Mr. Rodriguez, I want to start a small vegetable garden in my yard. However I just put out fertilizer and insect killer. What's the best way to leach the products from the soil so I can safely plant vegetables? How long will the process take?
Answer:
This is a question that I cannot answer. First, the fertilizer is not a problem. But the pesticide could be. Since I have no idea what this pesticide might be, I recommend that you first look at the label and see what it says about use in a vegetable garden. Also you should contact the manufacturer of the product to find out how long (if any) you should wait before planting vegetables in that area. Leaching it from the soil may not be an option while waiting out its viable life would be.

Question:
How can I keep the squirrels from digging up my plants? They keep getting into the bulbs.
Answer:
There are commercial products that are advertised to keep squirrels out of your beds but I cannot vouch for the effectiveness of any of them. You can lay something like chicken-wire over the planted area which will allow the plants to come up through but prevent the squirrels from digging.

Question:
David, I have a gravel yard that I have fenced for a small terrier. I would like to plant a bush for him to urinate on but don't want it to die. Any ideas on bushes, that urine won't kill?
Answer:
I don't know if such a plant exists that can survive the constant indignation of being urinated upon. I have heard that rosemary (Rosmarinus officinalis) might not be affected. I suspect that pet stores sell fake fire hydrants which would be a suitable substitute for a bush.

Question:
David, we landscaped our front yard last year and one of the plants we put in was dwarf hawthorns. This fall the deer stripped every leaf off and nibbled on liriope, day lilies as well. Can you suggest some kind of ever-green shrub to replace the hawthorns that deer don't like?
Answer:
See our list of deer resistant plants found at http://aggie-horticulture.tamu.edu/plantanswers/publications/deerbest.html. The two evergreen plants that have proved to be almost deer proof are Japanese Boxwood and Sandankwa Viburnum.

Question:
We bought some small hybrid live oak trees last fall and planted them in November. They are doing great, but we don't know how much to prune them. The trees are about 7-8 feet tall and the branches/greenery starts about a foot off of the ground. Should we take the lower branches off? If so, how high up should we go?
Answer:
You should not remove any of the lower branches until they are at least one inch in diameter. The tree needs every leaf at this stage to make the food for it to grow vigorously. This is called the 'trashy trunk' method of pruning. Once the branches reach that diameter you may remove them up as high as you need to be able to comfortably walk under the tree.

Question:
David, my Texas Gold columbine was gorgeous for four years and then stopped blooming two years ago. What could have caused it to stop blooming regardless of water and fertilizer? FYI, they never completely die back to nothing during summer - probably because of the mulch. I planted some hybrid columbine to add color in the last three years. I have the same problem for those in shady and partly shady areas. I'm stumped but want my golden blooms back.
Answer:
Columbines, while perennials seem to be weak perennials in our growing conditions. Normally they will reseed themselves. However, if you have mulch under them, the seed cannot make good contact with the ground and will not germinate to make new plants. They also need at least partial sun. This is why we recommend that they be planted under deciduous trees to give them full sun during the bloom bud setting and blooming time.

Question:
Mr. Rodriguez, how do you get rid of the native ground cover called Horse herb?
Answer:
This plant Horse herb (Calyptocarpus vialis) can be killed with a glyphosate herbicide like Complete. However, this plant reseeds itself prolifically and, you must prevent these seeds from germinating. This will require the application of a pre-emergent broadleaf herbicide which contains Dimension. After you have killed the plants, reapply the herbicide again in 3 to 4 months.

Question:
David, my lawn was originally sodded with Bermuda grass. For some reason, after the irrigation system was put in last summer, we have started seeing St. Augustinegrass trying to mix in with the Bermuda. I want the St. Augustinegrass gone, since the majority of the yard still is Bermuda. What do I do?
Answer:
Wait until the temperature is consistently about 75° F and then spray the area where the St. Augustinegrass is with a herbicide containing MSMA. This is commonly available in most nurseries/garden centers. It will kill the St. Augustinegrass, but will not harm the Bermuda. This product also works well in killing selected weeds in an established Bermuda lawn.

Question:
Each year my squash plants wilt and die about the time they start producing. Some have yellowish or greenish sawdust- like material all over the vines. What could possibly be wrong?
Answer:
More than likely, your problem is squash vine borers. If this is indeed the problem, the white, grub-like larvae can be found within the stem of the plant by cutting it open. The larvae hatch from eggs laid by a bright colored, wasp-like moth on the foliage or stems. The eggs hatch and the larvae travels down the plant to the stem and literally "core it out." To prevent this problem, begin control measures when the plants start to bloom by applying endosulfan (Thiodan) to the base of the plant. If the grubs are inside the stem, it is almost impossible to control. During the fall growing season, begin treatment shortly after plant emergence.

Question:
I bought a Yaupon Holly tree with red berries about 3 years ago. It has not put berries on since then. Do I need to buy another tree for it to set fruit?
Answer:
There are male and female Yaupon trees and you have to have both to have berries. The male does not have to be a Yaupon, but must be a holly with male flowers. This is normally not a problem as hollies are used in so many landscapes that there will be plants of both sexes in most neighborhoods.

Question:
I'm looking for an easy-care, non-invasive, blooming evergreen vine for a 7x4 trellis in full shade from May to late November. I would like an evergreen that doesn't need to be watered every single day in the summer.
Answer:
Aren't we all? Shade and bloom don't go together very well. You can try Crossvine (Bignonia capreolata) or Carolina Jessamine (Gelsemium sempervirens). Their bloom period is quite short in the early spring. Confederate Jasmine (Trachelospermum jasminoides) has a longer bloom period but may need more sunshine than you have.

Question:
When fertilizing trees do I need to: rake away all the mulch, spread the fertilizer, rewind soaker hose around tree, and then cover again with mulch?
Answer:
There is no need to remove the mulch. Just apply the fertilizer on top of the mulch and ensure that it gets watered in well.