The Gardener’s Dirt December 2014
This newsletter offers timely information for your outdoor living spaces. Addressing the
most common questions ranging from container gardening, tree pruning, wildlife management, to fire ant control, insect identification and lawn establishment.
Click here for a printable version of this newsletter.
Severe Pruning for Landscape Renovation
By Joanne King
I live in a well established neighborhood with lots of beautiful shrubbery across the front of the homes. After 15 years, some are screaming, “I want out!” At several houses, you can’t see the front door or the windows, and the sidewalk is difficult to navigate. Why do plants get to this state?
The first reason goes back to the adage, “right plant, right place.” It refers to the plants’ growing habits and the site in which it will be placed, such as sun/shade, height/width, shape, water requirements, and hardiness. There are also many plants that are suitable for either sun or shade, but grow best in one or the other. I have two viburnum evergreens, one in the sun and one in the shade. Guess what? The one in the sun is substantially larger than the one in the shade. This is not a problem for me, but can you imagine if this were a screen of plants? To get them to look uniform, you would have to continually shorten the sun lover.
A couple of examples of “wrong plant, wrong place” include:
(1) A homeowner inherits shrubs that were planted too close together, or too close to the foundation or the sidewalk. (For insect control, it’s not a good idea to have shrubs up against your house.)
(2) In an effort to produce an immediate visual impact, too many shrubs are planted, not allowing enough space for future growth.
(3) The plants are incorrectly labeled by the growers for the specific variety purchased
The second reason shrubs become too crowded is that the plants were neglected. Incorrect methods of pruning make it look better for a while, but may not be the best treatment for the plant. Plus, it is a lot of work.
Examples of treatment that is not the best include:
(1) Lack of pruning or improper pruning, forcing a plant into a shape not natural to its species.
(2) Over-fertilization, which promotes leafy growth at the expense of the flowers.
(3) Shearing plants to a certain height. You end up with nice greenery on top and thin branches at the base.
(4) Pruning frequently because you think you should. In the spring, this promotes top growth instead of growth throughout the plant. Fall pruning produces new growth, which is hurt by the first frost. You prune out the brown leaves and continue the cycle.
When shrubs get to an unsightly, overgrown state, two options to consider are removal or severe pruning. There are other less drastic methods to employ, but here we are talking do or die. So, we’ll save the less drastic measures for another article.
The pros and cons of removal include the expense of new plants and the cost/effort of the work. It is often difficult to remove a few shrubs without disturbing or damaging adjacent shrubs that will remain. You end up having to replace several shrubs because of one problem shrub. Of course, it depends on the landscape layout and the size of the plant to be removed.
For example, at my front door there are several loropetalums. These semi-evergreens were only supposed to get 4’-6’ tall. It would be okay if they got 4’ tall, but they usually reach 6’. They are easy to control with pruning, but I’m getting tired of doing so. Because there is space surrounding them, I can remove the shrubs without disturbing the other plants.
On the corner, there is very tall crepe myrtle. We inherited a 15’ tree living in an 8’ world. The squirrels climb it, run all over the roof, and build nests under the gutter guards. We have selectively pruned out the limbs closest to the house, but this has not solved the problem. If we prune the limbs down to a shorter height, we run the risk of “crepe murder.” The new branches will probably get to the roofline anyway. I cannot easily redo the landscape on this side because the crepe myrtle is so large and its roots are likely involved with the roots of all the adjacent shrubs. If I want to eliminate the squirrel highway, I will have to find an alternative way to prune, or pay someone to remove the tree and all the adjacent shrubs, hoping to salvage some of them.
Although seemingly drastic, when performed at the appropriate time, and with some patience, overgrown evergreens or deciduous shrubs can be salvaged. The technique is severe pruning or renewal pruning.
Severe pruning is generally for broadleaf evergreens, like hollies and ligustrums. It means pruning back radically to a height of 1’-4’, depending on the shrub. Remove all branches as well as any damaged trunks. The initial result will be an unattractive, short stump. Yes, it’s scary, but have no fear! When done at the correct time, which for most evergreens is late winter or early spring, the shrub will re-flush within the next season. It will put out new growth and ultimately provide a more manageable plant. You should selectively thin the new shoots to prevent crowding. Azaleas and other flowering evergreens can also be severely pruned, but you will lose the flowers in that year. They should return to a flowering state the following season. Because this is drastic pruning method, you will need to be willing to live with an ugly plant until new growth appears. This may not be a good solution at your front door, making removal an option to consider.
A less drastic approach is renewal pruning. Renewal pruning involves removing the oldest and thickest stems to just above ground level. What remains are the younger, more vigorous branches. This process will take several years to complete, as you do not want to remove more than 1/3 of the plant in any one pruning year. The root system will put out new shoots each year, leaving an attractive shrub during the process.
If you have questions about whether the plants you have can be severely pruned or what type of plant you actually have, take a branch or sample of the plant to your local extension office for identification and guidance.
Check out these links on pruning methods and pruning tools.
By Tina Stricklen
Now that we’re in fall-going-into-winter mode, it’s a good time to take a moment and look at the bones of the garden. Without distractions of annual and perennial blossoms and the myriad chores that keep us busy, it’s an opportunity to assess the garden structure. Evergreens play an important role year round, but the winter months are their time to really show their worth.
Tea olive is an evergreen that Southern gardeners covet. It has a dense growth with opposite, leathery, dark-green leaves that are 2 to 5 inches long. Reaching between 10 to 20 feet high and 10 to 14 feet wide, it makes a great hedge. Hardiness zones are 7 to 9, growing at a slow-to-moderate rate, Tea Olive should be sited in sun to partial shade.
One can grow it as a specimen plant but I love it so much, I’ve used it as a hedge in several places along the perimeter of my backyard. In fact, these 5 plants have been planted to create a small garden room. Here is a fun spot to sit and enjoy those delightful blooms that create that wonderful smell in the garden.
Tea Olive is a great plant for those who are into fragrance gardening. This plant is a real work horse, having few pests and is long-lived. It has proved to be much more reliable than the Daphne. Don’t get me wrong, I love the sweet fragrance of Daphne and will continue to try and grow it but it will wilt and die if you look at it wrong! All the literature says Tea Olive smells reminiscent of peaches, orange blossoms or jasmine but mine smell like apricots. It blooms heavily in fall but will also set a few blooms in the spring, fall and summer during moderate temperatures. Even with those cold snaps last month, there are a few blooms on my hedge right now (November 29th). See inset.
If you have room in your garden for Tea Olive, it’s worth the effort. It gives you year-round beauty, provides privacy if needed, and best of all will perfume your garden.
Are you looking for a way to serve your community while connecting with people of similar gardening interests?
Join the 2015 Master Gardener Class where hands-on learning and guest speakers provide practical, research-based Extension information on gardening issues. The $100 fee covers your manual, 40 hours of training, and other supplies. To learn more about MGs, go to www.ncstategardening.org.
The class begins January 22, meeting every Thursday for 13 weeks. Call Shawn at 919-989-5380 for more information!
By Shawn Banks
Gloomy scale is an insect that can be found on a variety of different plants but is usually the biggest problem on red maple trees. A healthy red maple has mottled gray bark that is relatively smooth to the touch. Infested trees have gray or black bumps on the bark making them quite rough to the touch. This gray or black look to the tree with no leaves on it produces a gloomy appearance, thus the name gloomy scale.
While the winter appearance of a tree that is severely infested with gloomy scale is that of a black or dark gray skeleton, the look of the same tree in the summer is very apparent as well. All the leaves will be tufted at the ends of the branches rather than spreading down the branch. The overall appearance of the tree is not pretty.
This insect is worse on trees that are either not well cared for or are under stress of some type. One way to combat this insect is to improve the overall health of the tree. Take a soil sample and adjust the soil pH according to soil test recommendations. Also, fertilize the tree in the spring. When we are going through a dry spell, water these trees to keep them healthy. After all, another common name for the red maple is swamp maple.
Another non-chemical method of removing the scale insects is to use a pressure washer on low pressure so as not to strip the bark off the tree. Reducing the number of scale insects feeding on the tree will help improve its health.
Horticultural oils can be used to suffocate the scale insects that overwinter as fertilized females on the bark of the trees. The highest concentration can be used as long as there are no leaves on the tree. Once the buds begin to swell in late winter, oils should be applied at the lighter rate so as not to damage the tree.
Dinotefuron is a systemic insecticide that can be applied to the ground around the tree in late winter (after the tree has finished flowering). The chemical will be taken up by the roots and distributed throughout the tree, killing the insects as they feed on the sap.
Crawlers (immature scales) begin emerging from under the shell of the female insects in May. At this point insecticides such as acephate (Orthene or Orthenex) may be sprayed on the trunk of the tree to kill the crawlers (the most vulnerable stage in the insects’ life).
Always read the label directions before making chemical applications. The label will tell you what personal protective equipment to wear and how to properly mix the chemical for the best effect.
Baker, James R. and Bambara, S. B., Gloomy Scalehttps://www.ces.ncsu.edu/depts/ent/notes/O&T/trees/note60/note60.html
BE CREATIVE, GO NATIVE!
By Margy Pearl
If you are looking for a shrub with fall and winter interest, one that attracts a variety of birds to your backyard, you’ll want to consider this drought tolerant native. American Beautyberry is best displayed massed in a natural area, or other sunny location in the Piedmont or Coastal Plain landscape. The arching stems may appear to be weeping but the large clusters of beautiful, glossy purple berries will make you smile!
Size: 3’ to 8’ tall and wide.
Form and Foliage: A semi-formal, oval to rounded form with open, arching branches. The opposite 3½” to 6” leaves, with toothed margins and light pubescence (tiny hairs) on the underside, give this deciduous shrub a coarse texture. The bright green leaves turn a lovely shade of yellow-green in the fall.
Site: Full sun to shade, in dry to moist soil, this drought tolerant plant can survive in a variety of conditions. For best flower and fruit production, however, plant in sun and in moist soil.
Flower: Flowering June through August, the small, white, pink, or light lavender-pink to bluish tubular blooms of the American Beautyberry appear on new growth at each axis (where the leaves meet the stem). This arrangement gives the appearance of blossoms surrounding the stem.
Fruit: The real beauty of this plant is the unusual ¼” pink-purple to red-violet fruit that surrounds the stem and matures late summer to fall. Ripening over a period of several weeks, this beauty’s purple berries provide a longer lasting food supply for the birds and an extended display of color for us.
Wildlife:The fruit is a very important fall food for migrant songbirds, the Northern bobwhite, gray catbirds, and other songbirds. Small mammals, white-tailed deer, and black bears also will browse on the fruit.
Maintenance: Flowering on new growth, this shrub should be cut back to 12” above the base in late winter or early spring to encourage more compact growth, flowers and fruit. As with many natives, there are no serious pest or disease problems.
Propagation: Propagation from seeds and softwood cuttings often result in failure.
The best way to obtain a seedling is to dig up one of the volunteers that are commonly found around mature plants in the fall. Be sure to ask other gardeners. Chances are good that someone has American Beautyberry seedlings to share!
Where they can be purchased:
Earthworks Nursery NCDA&CS Raleigh Farmers Market
30 Allen Rd. 1201 Agriculture St.
Clayton, NC 27520 Raleigh, North Carolina 27603
Tardevil@gmail.com (Earthworks has a booth there, too.)
Niche Gardens Cure Nursery
1111 Dawson Road 880 Buteo Ridge
Chapel Hill, NC 27516 Pittsboro, NC 27312
WHAT’S IN SEASON
By Chris Alberti
I have grown rosemary in my yard for many years. Rosemary likes a sunny to light shade environment with well-drained soil. It is very resilient and will tolerate salt spray, is deer resistant and can be severely pruned. This very aromatic plant can grow from 2’-6’ high and 3’-4’ wide. On several tours to the town of Beaufort, NC, I have noticed that many residents use rosemary as hedges. My guess is that this evergreen plant likes the sandy soil and tolerates the salty air well.
The soil for rosemary needs to have excellent drainage. Rosemary roots easily from stem cuttings but is very slow to develop from seed. When the cuttings are large enough to handle, transplant them in the ground leaving 2’ to 3’ spaces between the plants. Rosemary can be container-grown indoors in a sunny location. In the garden, it will survive best if it is watered from above since its leaves, as well as its roots, require moisture.
To cultivate rosemary, plant it in a sunny location and protect it from cold winds. In cold or exposed areas, grow it in a large pot. Sink it down in outdoor soil in the summer and return it to an indoor location for the winter. I live in Southern Wake County and have grown rosemary in large pots outdoors year round for about ten years, supplying all the rosemary needed for friends, neighbors, and my family. I pile 3”-4” of mulch across the soil surface and around the outside of the pot and keep the plant near the side of the house for protection from the winter cold.
To harvest rosemary, you can pick small amounts all year round; it tolerates cuttings well. Pull the leaves off the stems and use fresh or you can dry the leaves in the sun for a few days. The many uses for rosemary include teas, and flavoring for vinegar, jam, bread, butters, stuffing, vegetables, stew and meat dishes. I like making a marinade of olive oil and rosemary and spreading it over steak before grilling.
Here is a recipe from Fresh Herbs, by Barbara Radcliffe Rogers:
6 chicken breasts, skin intact
2 cloves garlic
3 tbs. olive oil
2 tbsp. fresh rosemary, chopped
15 woody sprigs fresh rosemary
Rub the chicken with crushed garlic, then olive oil. Sprinkle with rosemary and let stand 1 hour. Rub the grill surface with oil. Preheat the grill. Soak the rosemary sprigs in water for at least 30 minutes. When the fire is ready, place the chicken on the grill and sear for 5 minutes, then turn and sear on the other side. Place the rosemary branches around the chicken. Cover the grill and cook 20 minutes, turning at least once. After 20 minutes, turn the chicken again. If you have a gas grill, turn off and leave covered and undisturbed for 25 minutes. For charcoal grills, douse a little water on the coals to cool them, then close the grill and open the vents. Leave undisturbed for 25 minutes. Serve with a fresh rosemary garnish. Serves 6.
The Complete Book of Herbs, Lesley Bremness, 1988
Fresh Herbs, Barbara Radcliffe Rogers, 1990.
DECEMBER GARDEN TASKS
- If it hasn’t been done already fertilize cool-season lawns such as fescue. Roots of cool-season grasses continue to grow whenever the ground is not frozen.
- Cool-season weeds in established cool-season or dormant Zoysia or Bermudagrass lawns may be treated with broadleaf herbicides.
TREES, SHRUBS &ORNAMENTALS
- Prune evergreens to use for winter decorations in the house by cutting out unwanted limbs that would be pruned in February anyway. (Save major pruning for late winter.) Holly, Magnolia, Cedar, and Nandina foliage will last a long time.
- Many landscape shrubs can be propagated from hardwood cuttings including American holly and junipers Juniper.
- Prevent winter damage to plants from dessication (drying), freezing and thawing, and breakage from ice and snow loads. Keep plants watered during dry periods. Read ‘How to Protect Plants from Cold Damage’ at https://www.ces.ncsu.edu/depts/hort/hil/hil-604.html .
- This is an excellent time to mulch shrubs, trees, perennials, and herbs for winter protection. Apply a layer 3″ deep since most perennials are dormant and it’s easy to get a wheelbarrow into the garden. Mulch comparisons and general info: https://www.ces.ncsu.edu/depts/hort/hil/hil-608.html
- Weed out “weed” trees and shrubs. Prolifically-seeding plants like oak, elm, Mimosa Tree, hackberry, plum, and ligustrum (privet) produce numerous offspring which compete with other landscape plants for light, water and nutrients. Weedy woody seedlings are easier to remove while still young.
- Put your cut Holiday tree to use! Cut the branches and lay them over perennials to protect them from the cold. Shred small branches to make mulch.
- Do NOT prune fruit trees now. Fruit trees are best pruned late winter just before they start to grow in spring.
- Asparagus crowns can be planted now through March.
Giving gifts? Consider giving a good gardening book or accessory! Gardening is a gift all year round.
Build raised beds now for plant next spring.Find out why and how at:Raised Bed Gardening Made Easy.
Clean bird feeders monthly with hot sudsy water and diluted bleach to prevent the spread of wild bird diseases. Keep seed hulls from accumulating underneath the feeder to discourage rodents.
Check holiday and gift plants for insects before locating them near other plants.
If you have gardening questions you would like to have answered contact the Extension Master Gardener Volunteers by phone at (919) 989-5380 or by e-mail at email@example.com.
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