Trumptet Vine Spring 07 - Loudoun County Master Gardeners · used in cooking — basil, tarragon,...

Help Desk: 703-771-5150 - 1 - e-mail: [email protected]

Volume I, Issue 1 www.loudouncountymastergardeners.org

Volume II, Issue 2 www.loudouncountymastergardeners.org

Happy Birthday Loudoun County! Loudoun County was formed in 1757 when it sepa-rated from Fairfax County. The new county was named for John Campbell, the fourth Earl of Lou-doun. John was a wealthy Scottish aristocrat who was governor of Virginia (in name only) and com-mander-in-chief of British forces in North America at the time. Ironically, historians do not believe that Lord Loudoun was ever in Virginia.

The County Seat was named George Town and was located what is now the junction of routes 7 and 15. George Town was renamed Leesburg the following year.

On Saturday, May 19, Loudoun is celebrating 250 years of his-tory on the Courthouse lawn in downtown Leesburg. This trib-ute includes historians, musi-cians, historical record dis-plays, and Loudoun County Master Gardeners! Visit us to learn about horticultural prac-tices early Loudouners used.

2007 is also the 400th anniversary of Jamestown, the first permanent English settlement in the Americas. The Commonwealth of Virginia is plan-ning activities to honor America’s Anniversary.

As a tribute to these noteworthy anniversaries, Loudoun County Master Gardeners are researching, planning, and planting heritage vegetables in the Ida Lee Demonstration Garden in Leesburg. Read about this garden on page 8 and visit us as we harvest the produce our ancestors did. All pro-duce is donated to Interfaith Relief.

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fÑÜ|Çz ECCJ Knowledge for the Community from the Loudoun County Master Gardeners

LOUDOUN COUNTY MASTER GARDENER

MONTHLY MEETINGS

FREE and OPEN TO THE PUBLIC Meetings are held at the Virginia Tech Extension Office, 30B Catoctin Circle

SE, Leesburg at 7pm APRIL 5

“Deer in the Garden” Ellen and Bob Rummel are sharing-what they’ve learned about dealing with deer. Ellen is a Master Gar-dener. She and her husband Bob arein the VA Master Naturalist program.

MAY 3 “Twelve Common Garden Design

Mistakes” Landscape Designer and Master Gar-dener Becky Phillips is talking about common design mistakes.

JUNE 7 “Roses”

Donna Williamson is speaking on the easier roses to grow in our area. Donna started a garden design, in-stallation, and maintenance businessin 1988 and since has taught no-nonsense gardening at the State Ar-boretum of Virginia, Oatlands, Shen-andoah University, and others.

IN THIS ISSUE Feature Story 1 Gardening Events 2 Herbs 3 Spring Flowers 4 Spring Lawn Care 6 Spring Trees and Shrubs 8 Vegetables 9 Spring Gardening Tips 10

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Gardening Events

Apr 5 "What to do about Deer in the Garden" ― 30-B Catoctin Circle, Leesburg, 7 pm

Apr 14 Arbor Day celebration ― Banshee Reeks Park, Leesburg

Apr 21 – 22 Leesburg Flower & Garden Festival — visit the LCMG booth

Apr 28 Master Gardener Plant Sale ― 30-B Catoctin Circle, Leesburg, 10 am

May 3 “Twelve Common Garden Design Mistakes” ― 30-B Catoctin Circle, Leesburg, 7 pm

May 5 - 6 Oatlands Garden Fair — Oatlands Plantation, Leesburg, 10 am

May 12 - 13 Blandy Garden Fair, Blandy Experimental Farm, State Arboretum of VA, Boyce, VA

May 15 “Worms Eat by Garbage” (Vermicomposting) ― Ida Lee Demonstration Garden, noon

May 19 Loudoun County Anniversary Celebration, Courthouse lawn, Leesburg

May 19 - 20 Spring Farm Tour — Ida Lee Demonstration Garden, 10 am

May 22 “Planting America’s Anniversary Garden” ― Ida Lee Demonstration Garden, noon

May 29 “Square Foot Gardening” ― Ida Lee Demonstration Garden, noon

Jun 5 “Lasagna Gardening” ― Ida Lee Demonstration Garden, noon

Jun 7 “Roses” ― 30-B Catoctin Circle, Leesburg, 7 pm

Jun 12 “Water Quality ― How to Save the Bay” ― Ida Lee Demonstration Garden, noon

Jun 19 “Companion Planting” ― Ida Lee Demonstration Garden, noon

Jun 26 “Caring for Trees” ― Ida Lee Demonstration Garden, noon

Every Thur Purcellville Farmers Market — bring your questions, plants, even pests to our Gardening Clinics for diagnosis and recommendations, beginning May 3, 4-7 pm

Every Sat Leesburg Farmers Market — Gardening Clinics every Saturday, beginning May 5, 9 am

2nd Sun Cascades Farmers Market — another opportunity to speak with Master Gardeners, 9 am

4th Sun Lowe’s (Sterling) Gardening Clinic — 9-12 am

Check our website — www.loudouncountymastergardeners.org — for additional details and the latest information

Oatlands



Herbs

Herbs are various kinds of herbaceous plants whose fresh or dried parts are used to flavor foods, provide fragrances, offer medication, supply natural dyes, repel insects, and make in-dustrial or pharmaceutical products. Culinary herbs are ones whose fresh or dried leaves are used in cooking — basil, tarragon, rosemary, and thyme. Many modern medicines are derived from medicinal herb. Herbs are also enjoyed for their beauty in the garden or dried for wreaths, flower arrangements and potpourri.

In the next issues of the Trumpet Vine, we are going to help you discover a world of flavor, wellness, and fragrance via herbs. Most herbs grow well with the same sunlight, fertility, soil, growing conditions, and cultural techniques re-quired by vegetables.

Get ready for the surprising taste and aroma of fresh herbs from your garden!

? Do you know what plant is both a culinary herb and a medicinal herb?

? It is 20 times sweeter than sugar and doesn’t decay teeth.

We are planning a new Culinary Herb Garden as well as a new Medicinal Herb Garden this year at the Ida Lee Demonstration Garden. Come on out and gather some ideas! Look for Lunch & Learn dates about these two new gardens. The table shows what’s planned.

Janette Sawyer and Linda Shotton Master Gardeners

Culinary Garden Medicinal Garden

Angelica Lemon Balm Aloe Vera Lords & Ladies

Basil Lemon Verbena Arrowroot Skullcap

Bay Lovage Basil Stevia

Borage Marjoram Bay Sweet Annie

Caraway Mint Bloodroot Valerian

Chervil Oregano Borage

Chives Parsley Catnip

Cilantro Rosemary Cayenne

Curry Sage Chamomile

Dill Salad Burnet Comfrey

Fennel Savory (Winter) Curry

Garlic Chives Stevia Dill

Horehound Tarragon Feverfew

Hyssop Thyme Garlic

Lavender Golden seal



Spring Flowers

Master Gardener Sun Favorites!

Campanula ‘Pink Octopus’

This campanula has Japanese lantern buds that open to striking pink octopus-like

flowers. It’s an easy-to-grow, long blooming perennial that is deer-resistant and attrac-tive to hummingbirds. Noted

for its very unusual blossoms, Pink Octous is great in cutting gardens.

This exotic, interesting plant is a compact 15” x 18” mound and can be used as a border or in a

container.

Columbine - Pagoda ‘Rose and Ivory’

Rose and Ivory is part of the columbine pagoda series. This 14" x 12"perennial is

deer-resistant and attrac-tive to bees, butterflies, and birds. It’s great for

early spring color.

Primula ‘Corporal Baxter’

This primrose is great for early

spring color with large, scarlet double

flowers and green ribbed leaves.

Corporal Baxter needs partial-sun

and is a deer-resistant. Its compact 12" x 10" size makes it a

great container plant.

Huchera dolce ‘Peach Melba’

Peach Melba is a stunning, unique apricot and deep red

combination that changes colors with the seasons. It goes beauti-

fully with other plants in your garden.

This 16" x 14" coral bell is extremely versatile and can be used as ground-cover, in groupings, rock gardens, borders, open woodland, edging along paths or walkways, and containers. It’s

cold-hardy and deer-resistant.

Salvia nemorosa 'Sensation Rose'

'Sensation Rose' is the pink version of the dwarf Salvia 'Marcus.' The 10” x 12” plant has lavender-pink spikes that bloom from May – August and are quite the sensation. It re-flowers with deadheading.

It’s an easy-to-grow container plant, perennial border, addition to a wildlife garden — even cut flowers.

Veronica prostrata ‘Goldwell’

Cute, erect flower spikes of soft blue-purple bloom in May and June. The leaves are rich-green edged in gold and make a wonderful back-drop to purple flowers.

This 4” x 18” perennial has tremendous appeal when not in bloom. It’s a striking plant for ground cover, edging, containers, or sunny slopes.

Becky Phillips, Master Gardener

Master Gardener Shade Favorites!

Important! The average last frost date in Loudoun County is May 10th. If you plant prior to that date, be prepared to cover those tender plants on cold nights.



Master Gardener Shade Favorites!

Claytonia virginica ‘Spring Beauty’

As a harbinger of spring, these flowers bloom at the

end of February to early May. The flowers are

white with streaks to guide pollinators and give an

overall pink appearance. The foliage is slender and grass-like, and contin-

ues to grow after the flowers are gone.

Spring Beauty is 3” tall and naturalizes easily by bulb offsets and self-seeding.

Dicentra canadensis ‘Squirrel Corn’

Squirrel corn is a member of the poppy family along with

Dutchman’s Breeches and Wild Bleeding Heart. It

blooms April through May. The name comes from its

tuberous roots resembling kernels of corn and the habit of squirrels digging

for food combined to form the common name.

The plant is 6” – 12” in height.

Geranium maculatum ‘Cranesbill’

Beak-shaped seed pods give Cranesbill's their name. They have light pink to

purple flowers from late spring to early summer. It spreads and makes a very

nice size clump quite quickly.

The whole plant — especially the root — is antiseptic, highly astringent, diuretic, styp-

tic, and tonic. Cranesbill makes an attractive groundcover.

Mertensia virginica ‘Virginia Bluebells’

One of early to mid-spring's most delightful sights in the wild or in the garden is the

Virginia Bluebell. They flower continuously from late March to May, then quickly go dor-

mant. The pastel colors of the flowers and foli-age are soft and soothing, making this a tradi-

tional favorite.

These spread rapidly via rhizomes and seed. Plant in moist woods with ferns.

Sanguinaria canadensis ‘Bloodroot’

One of the first and showiest of the early spring bloomers — called

Bloodroot because of its red sap — are a welcome sign that spring is on

the way. The green leaves stay through the growing season.

Bloodroot is 2-3" and produces a seed capsule that can produce a nice little colony in

your garden.

An extract of this plant has long been used in toothpaste and mouthwash to fight plaque and

gingivitis (sanctioned by the FDA). Researchers are now investigating the root's value in cancer

treatment.

Trillium sessile ‘Wakerobin’

Wakerobin is a simple, graceful perennial that is one of the most familiar

and beloved of the spring woodland wildflowers.

Leaves, petals and sepals of all trilliums come in

groups of three. The flowers have a slightly sweet fragrance.

This classic spring-bloomer is excellent when massed in a shaded woodland garden or natural-ized area — or mixed with other spring wildflow-

ers and ferns.

Carol Ivory, Master Gardener



Spring Lawn Care As the grass greens up, many homeowners are anxious to get out and start working on their lawns. A little patience and care at this point can reward you with a fine lawn later.

For instance, the sight of new grass growing often inspires the homeowner to run out and spread fertil-izer to help the young blades along. This is actually the opposite of recommended practices for fescue and bluegrass lawns. The proper time to feed grass is in the fall, when the roots that sustain the plants through the following summer are actively growing. If the fall feeding was missed, any spring feeding should be limited to a light feeding (½ pound of actual nitrogen, i.e., 5 pounds of 10-10-10, per 1000 sq. ft.) after the initial flush of growth has subsided, sometime in May or early June.

Lime, on the other hand, should be applied in early spring, if soil tests indicate that it is necessary. Most lawn grasses grow best at soil pH's of 6.0 to 7.0, so have your soil's pH analyzed every two to three years to be sure you are staying in that range. (ed note: Soil tests are available from your local extension office. Costs for the test include shipping and a $7.00 handling fee.)

The best time to establish a new lawn from seed is in the fall, but many homeowners need to reseed patches of lawn that have been damaged during the winter. Seed sown during March and early April has a chance to grow successfully if it is well watered and cared for, from seeding on through the heat of summer. It is a good idea to fertilize newly seeded grass using a high phosphorous fertilizer (for ex-ample, 25 pounds of 5-10-5 per 1000 square feet when patch seeding) that fosters root growth. The grass grows stronger and healthier if you can water daily until the plants are established. Water about once a week throughout the summer, for the tops of the grass may look great, but the roots are not as long and dense as those of the grass in an established lawn.

There are many varieties and types of grass seed from which to choose. Your county Cooperative Ex-tension Agent can supply you with a publication that discusses selection of turfgrasses in Virginia.

When your lawn requires its first cutting, be sure not to cut too short. Mow about 2” during the spring, then raise the cutting height another ½” when summer arrives. Mow frequently so that no more than one third of the grass blade is removed at one time.

Along with your grass, several undesirables are probably growing in your lawn. The best prevention for a weedy lawn is to provide such great growing conditions that the turf crowds out the weeds. If the weeds are sparse, use that early spring energy to hand-pull some of those perennial weeds. There are chemicals that can be used if you have more weeds than energy. If you choose to use herbicides, be sure to apply them when they have maximum impact on the weed population. Follow label directions closely for information on time of application and safety precautions.

Apply preemergent herbicides between the middle of March and the middle of April to control crab-grass. Crabgrass generally emerges about the time of dogwood bloom, and the preemergent herbicides used to control it do not affect crabgrass that is already up and growing.

Spraying for dandelions is most effective in fall, but spring spraying of a broadleaf weed killer can con-trol many of them. Be sure to spray when the weeds are actively growing rather than during drought conditions. When spraying any herbicide, use a different sprayer from the one which you use to apply insecticides or fungicides. Mark it "HERBICIDE" so it is not inadvertently be used for other purposes, which may result in herbicide residues damaging valuable plants.

March is still a little early for dethatching and insect control, so after taking care of the few necessary lawn chores for early spring, you can relax and save your energy for summer mowing.

Prepared by Ellen Silva, Extension Technician, Department of Horticulture, Virginia Tech

(ed note: The Virginia Tech Website is the home to an amazing amount of information — all aimed at the climate in VA. For more information on spring management of your turf, please see: http://www.ext.vt.edu/pubs/turf/430-532/430-532.html



Corn Gluten Meal Look! Inside that bag! It’s a Weed Preventer! It’s an Organic Fertilizer! It’s …… CORN GLUTEN MEAL!

I’d like to introduce you to the new Superman of Organic Gar-dening Products: Corn Gluten Meal (also known as CGM). In the early 1990s, Dr. Nick Chris-tians of Iowa State University

discovered that this by-product of animal food processing has the unique ability to prevent the growth of roots on sprouting seeds, causing them to die. This patented product is now marketed as a natural weed-and-feed for use on lawns, vegetable and flower gardens.

Because I try to be a good Master Gardener, I don’t use chemical fertilizers on my lawn in spring when excess nitrogen in runoff causes the most harm to the Chesapeake Bay. However, spot treating the dandelions in my lawn with a broadleaf weed killer caused a curious phe-nomenon. Yes, the plants seemingly twisted in agony as they turned brown and wilted, but their intense desire to reproduce was evidenced by the yellow flower heads of the sprayed dan-delions turning overnight into fluffy stalks of hundreds of seeds! While I was killing the exist-ing dandelions by spot chemical control, the plants were sending out seeds that would germi-nate in my lawn, ensuring their survival.

Enter our Organic Crusader: Corn Gluten Meal. By spreading the pale yellow, slightly starchy scented powder on my lawn, the dandelion seeds would germinate, but would be unable to sustain growth, ending the cycle of new weeds appearing like villains in the lawn. I experi-mented on two different sections of my front yard (separated by the driveway) and found that the side treated with CGM in April had signifi-cantly fewer dandelions (probably only the ones missed by the original spot treatment) in July as compared to the untreated side.

Corn Gluten Meal is applied to your lawn or gar-den the same way you would spread fertilizer — by hand or mechanical spreader, always follow-

ing package directions. It remains effective as a pre-emergent weed control for about three months, depending on the amount of rainfall received. Repeat applications help keep the area weed-free as well as fertilized with a small amount of slow-release organic nitrogen. It is important to understand that you cannot plant grass, flower or vegetable seeds in an area treated with CGM. The same process that inhib-its the growth of roots in weed seeds keeps any type of seed from growing. CGM has no detri-mental effect on transplants. You can always start your seeds in an area that was not treated then move the established plants into the treated zone. CGM does not kill existing weeds; it only prevents new weed seeds from growing. CGM is recommended as a pre-emergent control for crabgrass, curly dock, dandelions, lambs quarters, pigweed, and plantain.

So where does one find CGM? It’s available un-der a variety of manufacturer’s labels including Cock-a-doodle-doo, Garden’s Alive WOW, and Concern Weed Prevention Plus. Preen is offer-ing a brand of CGM targeted specifically for vegetable gardens this year. CGM is available locally at various nurseries and garden centers including Blue Mount Nursery, John Deere Land-scape Design, Merri-field Garden Center, and Southern States.

Corn Gluten Meal has been a Super Hero in reducing the weeds in my lawn. This year I’m going to try it in and around some of my vegetable beds. Hopefully, I can spend less time weeding and more time enjoying my harvest this year.

For more information on Corn Gluten Meal, visit: http://www.gluten.iastate.edu/links.html

Judy Stroske, Master Gardener

Dr. Nick Christians



Trees and Shrubs Spring Pruning

Your spring pruning should be very judicious. First focus on the three D’s of pruning: Dead, Diseased and Demented.

• Examine your trees and shrubs for dead wood. Even a healthy plant has some branches, twigs or tips that have not survived the winter. Roses and vines often have significant dieback. These are the first to go.

• Remove anything that doesn’t look healthy. Examine rhodo-dendrons and mountain laurel for diseased leaves and twigs. Remove canes that are too thin.

• Eliminate things that don’t look right, crowded branches, crossing branches, branches that are growing in instead of out and anything growing straight up on a weeping tree.

Cut back ornamental grasses fairly close to the ground but be careful not to cut the new, emerging foliage. Finally, spring is a good time to rejuvenate old plants. You can cut down to 2” to 12” from the ground the following shrubs if they are badly overgrown: Privet — Cut back hard in April.

• Forsythia — After flowering, remove old branches down to the ground. Shorten the remaining long shoots by heading back cuts to an outside facing branch or bud.

• Abelia — Prune before new growth begins. • Butterfly bush — Prune before spring growth. • Smoke bush or smoke tree — Prune in spring to cut out the oldest, woodiest stems — can be cut

down to the ground.

• Pee gee hydrangea — remove 1/3 of the oldest canes. • Pussy willow — Harvest the tops bearing catkins. Then cut 1/3 of the oldest branches back to the

ground. The oldest branches are the gray-colored ones. Shorten the remaining branches.

Carol Ivory, Master Gardener

Spring Plant Sale!

Visit Loudoun County Master Gardener’s Spring Plant Sale on Saturday, April 28th from 10 am until 4 pm at the Extension Office parking lot (Wachovia Bank building). This is your chance to purchase Master Gardener-grown tomatoes, peppers, herbs, companion plants, and perennials!

Support your community’s volunteer organization!



Vegetables Celebrating Loudoun County’s Heritage with Heirloom Vegetables

Remember back to the best vegetable you have ever tasted! Do you know what it was or where it came from? Chances are it was an heirloom vegetable. This year the Master Gardeners are growing heirloom vegetables in the Ida Lee Demonstration Garden at in recognition of Lou-doun County’s 250th birthday.

Heirloom vege-tables are enjoy-ing a tremendous resurgence in popularity be-cause gardeners and consumers alike have dis-covered the in-credible taste and quality of old style varie-ties. As with many things in

life, there is widespread debate about what can be called an heirloom. Many people would ex-clude commercial varieties sold prior to 1951 and include only those that were regionally cre-ated and passed from generation to generation by seed saving among families. Still others would only consider varieties sold prior to 1920 as worthy of heirloom status. The generally ac-cepted definition of an heirloom is any old, open-pollinated cultivar discovered before 1951, which is high in quality as well as being easy to grow. In the Demo Garden we are growing vege-tables representing the years 1771 – 1889.

Names of heirloom varieties often tell the story of the vegetable. The “Kentucky Wonder” pole bean was originally known as “Old Homestead” but was renamed when in 1902 it was reportedly the most widely grown pole bean in the US be-cause the bean was prolific, hardy and resistant to disease while retaining its tenderness and taste. Another bean, Cherokee Trail of Tears,

was a snap/dry bean carried by the Cherokees over the “Trail of Tears” in 1838. Thomas Jef-ferson was known for his experimentation of many different vegetables. “Tennis Ball” lettuce was one of his favorites. The miniature butter-heads actually do resemble tennis balls. The White Wonder” cucumber is so named because the fruits are white along with exponentially in-creasing production as the mercury rises during the summer.

Individuals and seed saving organizations are re-sponsible for keeping heirloom vegetables going through the years and in some cases, hundreds of years. Some seeds are quite rare and hard to find. Today with Internet search capabilities a great deal of information can be found online. When searching, you should try to find specific heirlooms that have a good chance to grow in our local climate and meet your taste expecta-tions. In our area, Southern Exposure Seed Ex-change sells heirloom seeds specifically for the Mid-Atlantic region and is a good place to start in your search for knowledge and seeds to grow at www.southernexposure.com.

While heirloom vegetables may be a bigger chal-lenge to grow as they are not bred specifically to resist certain diseases and pests as hybrids are, they reward you many times over with their superior taste. We invite you to visit the vegetable section of the Demo garden in the coming months to learn more about heirloom vegetables and to compare notes about your experience with heirlooms.

Denise Palmer, Master Gardener



Spring Gardening Tips Help Desk Frequently Asked Questions

This is a new feature of the Trumpet Vine — sharing the frequently-asked questions we receive on the Help Desk — as well as the answers. The Help Desk is staffed Monday through Friday from 9 am to 12 noon. You can call 703-771-5150 with your questions.

Plant Diagnosis — Brown / Dead Branches on Leyland Cypress

Q: I planted a row of Leyland cypress along the boundary of my property to act as a screen to the street beyond. They did fine for a few years, but now one of the trees has limbs that have browned out and died. It looks like the trees on either side are starting to develop the same problem. What is causing this and what can I do to save my screen?

A: The Leyland cypress (x Cupressocyparis leylandii) has been widely planted in this area because of its desireable characteristics of lush evergreen foliage and fast growth rate. Now, throughout the south, many Leyland cypress are falling prey to two canker dis-eases that result in the kind of symptoms that you describe. The most common is the seiridium canker (Seiridium unicorne), but similar symptoms are caused by the botryosphaeria canker (Bot-ryosphaeria obtusa). Cankers appear as sunken areas on stems or branches, and the twigs or branches turn bright reddish brown and die. Eventually, the entire tree may become infected and die. The fungus is spread by spores through water splashes from rain or irri-gation or from tree-to-tree on pruning tools. Spores from the bot-ryospheria canker can also be spread by the wind. To verify if this

is indeed the problem with your trees, bring a sample in to the Ex-tension Office Help Desk for analysis. Try to cut a sample that shows the transition from living to dead plant material and includes any cankers you find on the branches.

There are no chemical recommendations for halting this disease. Infected twigs or branches should be pruned out and destroyed as soon as they are noticed. Prune the branches about 1” below the canker. Sterilize your tools after pruning an infected tree. You can use rubbing alcohol or a bleach mixture that is 1 part bleach to 9 parts water. Be sure to clean and oil your tools after using the bleach mix-ture to avoid rust.

To reduce the possibility of this disease spreading to your other trees, follow good cultural practices. Provide plants with adequate water during drought periods and mulch with 2 inches of organic mate-rial, being sure to leave a few inches between the trunk and the mulch. Do not overstress established trees with heavy fertilization or pruning.

This question illustrates one of the problems with creating a monoculture in your landscape, i.e., using only one cultivar or species. A single pathogen will usually not destroy an entire screen that consists of a diverse group of plants. You may want to consider replacing some of your Leyland cypress with other evergreens that are appropriate for your setting. Access the Virginia Cooperative Extension pub-lication, Trees for Problem Landscape Sites: Screening, at: http://www.ext.vt.edu/pubs/nursery/430-025/430-025.pdf or call the Help Desk at 703-771-5150 for recommendations.

Dieback on Leyland Cypress (photo by J. Williams-Woodward)



Plant Diagnosis — Spots on Dogwood

Q: My white flowering dogwood was covered with beautiful “flowers” last spring (I know they are really bracts), but shortly after they emerged the bracts and the leaves developed small, purplish spots, all about the same size, with a white center that later dropped out altogether, leaving the leaves with a shot-holed appearance. Is this the fatal disease that I have heard about that is attacking dogwood in this area? Will my tree survive?

A: The good news is that the symptoms you describe sound like those of the spot anthracnose (Elsinoe corni) disease which is quite common but is rarely fatal to dogwood. The other disease, commonly called Discula anthracnose (Discula destructive), is characterized by spots that are not as uniform and may come together to blight the entire leaf and eventually cause dieback and death of the tree.

Spot anthracnose is most common in Cornus florida, with the pink culti-vars being somewhat less susceptible than the white. Trees planted in full sun tend to be more susceptible (though the opposite is true for Discula anthracnose). The small spots, less than 1/8”, may be quite numerous and the leaves or bracts may become puckered or distorted around the spots as the leaves expand. This disease does not cause die-back of branches and the spots do not enlarge, but symptoms can be severe when spring weather is cool and wet.

Control measures are usually not necessary. However, if the disease was severe in the previous year or a cool, wet spring is anticipated, spraying with fungicide may be warranted. You will need to apply a fungicide containing the active ingredient chlorothalonil (found in products such as Daconil WeatherStik, Ortho Daconil 2787, or Daconil ZN) according to the directions on the label when buds begin to swell and open. Repeat this treatment three times: when bracts have fallen, 4 weeks later, and in late summer after next year’s flower buds have formed. Be sure to follow good sanitation practices by removing all fallen leaves from the tree and also follow good cultural practices to keep the tree as healthy as possible. Make sure the tree is watered during droughts and is mulched well with 2” of organic mulch that does not touch the trunk of the tree.

For more photos and information on dogwood diseases access Virginia Cooperative Extension publica-tion, Foliar Diseases of Dogwood at: http://www.ext.vt.edu/pubs/plantdiseasefs/450-611/450-611.pdf.

Caution: Termite Season is Coming! Can you tell an ant from a termite?

Winged termites are often confused with winged ants. Because ter-mites can cause severe structural damage it is necessary to be able to identify them. To tell the differences between winged termites and winged ants, look at their waists. An ant has a narrow, wasp-like waist and a termite has a broad waist. The antennae or feelers of ants are L-shaped termites’ are straight. The four wings of termites are equal in length and nearly twice as long as the termite body. Ant wings are approximately the length of the ant and the fore and hind wings are not the same length.

Symptoms of spot anthracnose on bracts of flowering dogwood.

(Photo by M. A. Hansen)

Symptoms of spot an-thracnose on leaves of flowering dogwood.

(Photo by M. A. Hansen)



Spring Gardening Activities

For your lawn:

Control crabgrass before it germinates with a pre-emergent herbicide — not a fertilizer (early April)

Get your mower blades sharpened before the season begins

Leave grass clippings on the lawn to add nitrogen to the soil

Pour boiling water on unwanted grass and weeds in driveways and sidewalks

In the flower bed:

Divide perennials and prune roses (April)

Plant tender, summer-blooming bulbs (be-gonias, caladiums, cannas, dahlias, and gladiolas)

Start seeds indoors (April) to transplant outdoors (May) after hardening

Mix flowers and herbs so pests aren’t at-tracted to one location

Fertilize roses once a month with 5-10-5, look for lack spot and apply organic fungi-cide like sulfur or copper-containing soap

Deadhead flowers for continuous bloom

Pinch back chrysanthemum until mid-July to promote fullness and fall bloom

Control unwanted “volunteers” and weeds with mulch, cultivation or hand-picking

Check for signs of disease or insect damage and treat accordingly

Pick Japanese beetles off before 8:00 am (when they wake up) and put them into soapy water

For tress and shrubs:

Prune twigs and branches affected by win-ter kill after new growth begins

Prune spring-flowering trees / shrubs after they bloom (forsythia, wiegla, spirea)

Pinch back candles on evergreens to ½ to thicken

Look for tent caterpillars bagworms and de-stroy them

Mulch out (not up), 2-4” is plenty

Fertilize trees if leaves are small, sparse, and / or pale

Do not prune summer or fall bloomers

Use organic insect and disease control on fruit trees

In the garden:

Start seeds indoors (April) to transplant outdoors (May) after hardening

Plant and / or transplant strawberries, raspberries, and other small fruits

Plant cool crops (broccoli, cabbage, cauli-flower, lettuce, peas, potatoes, radishes, and spinach)

Plant succession crops every three weeks to extend harvest (corn and beans)

Keep fruits and vegetables well-watered, mulch with straw to keep moisture and re-duce weeds

Fertilize crops with manure tea

Control pests with insecticidal soap or soapy water

Debbie Dillion is the Urban Horticulturist and coordinator of the Master Gardener Volunteer program in Loudoun County. She can be reached at 703-771-5838.

Virginia Cooperative Extension programs, activities, and employment are available to all people regardless of race, color, religion, sex, age, national origin, handicap, or political affiliation. An equal opportunity / affirmative action employer.

Trumptet Vine Spring 07 - Loudoun County Master Gardeners · used in cooking — basil, tarragon,...

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Transcript of Trumptet Vine Spring 07 - Loudoun County Master Gardeners · used in cooking — basil, tarragon,...