Yard & Garden Line News
Volume 5 Number 5                                                               April 15, 2003
Features this issue:
 What You Need to Know Before Digging in Your Yard
2003 All-America Selections Awards Announced
Y & G Line 888 Service Discontinued
Powdery Mildew of Houseplants
Four New My Favorite™ Garden Chrysanthemums Available
Editorial Notes


What You Need to Know Before Digging in Your Yard
Gopher State One Call

Would you partake in any activity where you pose a high risk to yourself and your family of danger in the form of explosion, electrocution, or at the very least, will cost you hundreds of dollars? Most of us would give a strong "NO!" to that question. Yet, most of us won't think twice before putting a shovel in the ground to plant that tree or rent a skid loader for a weekend for a landscaping project.

Our nation has seen more of a 'do-it-yourself' trend this last decade. We are saving money by not hiring a contractor to add a deck or even plant a tree. Most of us are sure that we covered all of our bases; we heard about calling before you dig, but think that doesn't apply to us because we are only scraping the sod or digging a few feet. There is no way that any utility could be that shallow, right? WRONG!

Utility installation is only regulated at the time of installation. So after years of freeze and thaw, erosion, or even a previous owner who remodeled the lawn could affect the depth of all utilities. Simply digging with a shovel can seriously damage utilities. Surprisingly, it doesn't take much for a 150 pound person to cut through a telephone or cable line.

The easiest way to protect yourself and the utilities underground is to call before you dig! One call to Gopher State One Call will get all of your public utilities marked such as cable TV, phone, water, sewer, electric and gas. Be aware that if you have a privately installed line such as a pool heater, gas grill or electric/phone line from the house to a detached outbuilding, it will NOT be located by the utility. These private underground facilities are the homeowner's responsibility.


Planning ahead and knowing what is underground on your property will save you time and money in the long run. Once a call is made to Gopher State One Call, the utilities have 48 hours, excluding weekends and holidays, to mark their facilities on your property. They will use paint and/or flags in the color assigned by the American Public Works Association. These colors are important to remember, they are:
Red = Electric
Blue = Water
Orange = Telecommunications
Green = Sewer
Yellow = Gas
After you have waited the 48 hours and are ready to begin your project, hand dig 2 feet on either side of the markings to expose and find that facility underground. Visually inspecting the facility is the only way to properly know its depth.

What sorts of projects require a call? If you are a new homeowner and are not familiar with your property, it would be wise to call before starting any type of project. If you are tilling an existing garden or planting bulbs in an area you have planted before, calling is not necessary, but always an option if you can't remember where a utility was buried. It is required by MN State Statute 216D to call if you are moving or disturbing the earth by mechanical equipment. (MN State Statute 216D, Subdivision 5.)

The key message is to be safe when digging no matter what the project size or detail. The underground world is getting very congested and as a homeowner it is always wise to plan ahead and call Gopher State One Call. Visit our website for more homeowner-friendly information at www.gopherstateonecall.org. To call in a locate request in the metro area, call 651-454-0002, greater MN call 800-252-1166.

2003 All-America Selections Awards Announced
Deborah Brown, Extension Horticulturist

'Purple Majesty' ornamental millet.. Photo credit: All-American Selections
'Prairie Sun' rudbeckia. Photo credit: All-American Selections
'Blue Wave' petunia. Photo credit: All-American Selections
''Jaio Dark Red' vinca. Photo credit: All-American Selections
Here's a rundown of some of the 2003 All-America Selections award-winning annuals you'll see in catalogs and local garden centers:

Winning selections include something for everyone – one summer squash, one melon, a decorative herb, an ornamental millet, and eight different flowers, two of which may even behave as short-lived perennials in our climate. Many of these new cultivars are available as seeds to start indoors or direct seed in the garden. You should also be able to find them sold as bedding plants or in individual containers at some local nurseries and garden centers. These are the ones that looked most promising to me:

‘Purple Majesty' ornamental millet, winner of the All-America Selections gold medal for achievement in horticulture, is by far the most unusual and innovative new plant on the list. It looks like a corn stalk, three to five feet tall, topped by a large spike of tiny flowers that produce millet seed when mature. Its color – stalk, leaves, and all – is the darkest mahogany/purple imaginable.

This heat and drought tolerant annual serves many purposes. As a tall, dark plant, it works well at the back of a garden or perennial border. And its immature flower spikes may be cut for use in bouquets and floral arrangements. Be sure not to pick them all, though. Spikes that are left on the plant will attract birds that will snack on the seeds.

‘Prairie Sun' Rudbeckia hirta is a rudbeckia with distinctively colored blooms. Its large, five inch flowers have gold petals tipped with primrose yellow. But instead of the typical brown center cone found in many rudbeckias, ‘Prairie Sun's' is light green. The overall effect is softer and more subtle than that of most rudbeckias.

Like the ornmental millet, ‘Prairie Sun' rudbeckia grows best in full sunlight, where it will bloom from mid-summer on. It reaches about three feet in height, so may be planted in large containers as well as massed in the garden, where it may come back from the roots or self-sow. ‘Prairie Sun' has flower stems that are long enough so its daisy-like blooms may be used as cut flowers. (They last well, but will be best when picked shortly after opening fully.)

‘Blue Wave' petunia is the latest in the "wave" series of spreading petunias, following the ever-popular ‘Purple Wave' and ‘Pink Wave.' I find names like ‘Purple Wave' and ‘Blue Wave' a bit misleading, though. ‘Purple Wave' has brilliant red-violet flowers; ‘Blue Wave' has blossoms I would characterize as being a velvety deep purple – well, bluish purple, anyway.

Like its predecessors, ‘Blue Wave' grows only four to seven inches tall, but spreads several feet over the course of a growing season. It's a wonderful plant for hanging baskets and large containers where it can be allowed to trail over the sides. It's also excellent in a sunny garden where it behaves as a ground cover. To keep it blooming freely, it's important to fertilize ‘Blue Wave' (as well as any other spreading petunia) frequently, regardless of whether it's growing in a container or in the garden.

‘Jaio Dark Red' vinca (Catharanthus) is the first truly red vinca on the market. We've had white, pink, rose, and lavender cultivars, including several with contrasting centers, but no red. ‘Jaio Dark Red has 2 ˝ inch blossoms, each with a pure white eye, and glossy green foliage. Plants are compact, about fifteen inches tall and as much as twenty inches across when growing in full sun.

Flowering vincas are quite versatile; ‘Jaio Dark Red' is no exception. It tolerates heat and drought and is one of the few plants that will bloom in shadier dry locations, though flowering will be more prolific if the plant receives plenty of light. It's equally at home in containers and ground beds where it may be massed or used as an edging plant. As a bonus, neither insects nor deer are reportedly attracted to this plant.

‘Forever White' eustoma is a cultivated form of prairie gentian. You may also have heard this flower called "lisianthus." As its common name implies, the native prairie gentian thrives in dry, well-drained soils and full sunlight. So does ‘Forever White' eustoma. There are two major differences, though. The cultivated form is far more compact than its "wild" ancestor and its flowers are larger and showier.

‘Forever White' eustoma has beautiful ivory-white blooms that look like delicate rosebuds at first, then unfurl to become cup-shaped flowers, 2 ˝ inches across. The plant itself grows to about twelve inches, which means it's ideal for use in containers. Just be sure to pair it with other sun-loving plants that don't like to stay too moist.

‘Merlin Blue Morn' petunia has interesting flowers that progress gradually from pure white in the center to dark, velvety, bluish-purple on the edges. This color change, which is apparent from quite a distance, gives a softer look than picotee petunias. (Picotee petunias have a large center that's one color and a narrow, but sharply defined border of another.)

‘Merlin Blue Morn' grows about fifteen to twenty inches tall and spreads from eighteen to thirty inches – not as much as the "wave" petunias, but enough to recommend it for use in hanging baskets or large containers where its spreading branches can hang down gracefully.

Other All-America Selections for 2003 include ‘Corona Cherry Magic' dianthus (pinks), ‘Sundance Bicolor' gaillardia, ‘Can Can Scarlet' carnation, ‘Golden Jubilee' agastache (a compact anise hyssop that actually looks nutrient-deprived to me), ‘Papaya Pear' summer squash, and ‘Angel' melon.

Y & G Line 888 Service Discontinued
Beth Jarvis, Project Coordinator


In response to deep funding cuts, the Yard & Garden Line's toll free phone access, 888-624-4771, was terminated April 2. Anyone wishing to call the Yard & Garden Line from outside the Twin Cities metro calling area will need to dial 612-624-4771. The Yard & Garden services remain the same--providing one call access to Master Gardeners, Soil Testing Lab, INFO-U, Extension's Distribution Center, Bell Museum's wildlife help line

In a related move, the Master Gardener voice mailboxes were modified. Callers from Greater Minnesota will be referred back to their county offices. Calls in the Metro will continue to be routed to Master Gardener voice mailboxes in their county.

Powdery Mildew of Houseplants
Janna Beckerman, Extension Plant Pathologist

Indoors, rosemary is often infected by powdery mildew Photo credit:  Janna Beckerman
Powdery mildew produces copious spores.
Illustration: Yard & Garden.
Cleistothecia are the sexual, overwintering stage. Photo credit: Janna Beckerman
Regular sprays of water reduce the incidence and severity of powdery mildew. Photo credit:  Janna Beckerman
Powdery mildew is one of the most common plant diseases, not only of agricultural crops, but also landscape ornamentals and even houseplants. Even though these diseases look the same to the naked eye, powdery mildew is actually caused by thousands of different (but closely related) fungi. In most instances, powdery mildews are very host specific, i.e, the powdery mildew on your lilac (caused by Microsphaera syringae ) is a different species than the powdery mildew on your rose (caused by Sphaerotheca pannosa), and therefore lilac powdery mildew cannot cause powdery mildew on rose.

Symptoms of Powdery Mildew. Fortunately, of all the diseases, powdery mildew is one of the easiest to diagnose. Powdery mildews appear as a dusty white powder coating the leaf surface. Severe infections may result in this "powder" (which is composed of thousands of spores) spreading to other plant parts. In most cases this fungal growth can be partially removed by rubbing the leaves. If infection is light, powdery mildew can be misidentified as dust accumulated on the leaves. On houseplants, symptoms may occur at any time of year, but usually develop in late winter to early spring. Symptoms such as yellowing or leaf drop may develop as a result of the powdery mildew fungus removing nutrients from the plants.

Because all of these powdery mildew fungi are so closely related, they have similar lifecycles. This makes our lives easier because this also means that they have similar management practices. Houseplants that are commonly infected by powdery mildew include African violet and begonia. Bedding plants like hydrangea commonly sold as seasonal houseplants, often develop powdery mildew. Herbs such as rosemary will develop powdery mildew when brought indoors for use as a houseplant. The actual injury that results from infection by powdery mildew fungi varies greatly with the species and even the variety of plant attacked. For instance, begonia is seriously injured or even killed by mild infection. Plant death results when the tissue being colonized by the fungus dies soon after infection. These small lesions often result in leaf drop and poor plant growth. Thorough management practices must be implemented in the case of begonias infected by powdery mildew because plant death can quickly result. Infection by powdery mildew, in the case of herbs, does not render the plant inedible.

How this disease spreads. The fungi that cause powdery mildew are spread by spores produced in the white patches on the leaves and stems of infected plants. In fact, most of the white patches that you see are the spores! Infection by powdery mildew to houseplants can result when spores are blown in the wind to other parts of the plant or to other plants during the growing season, although with houseplants, this is unusual. Most houseplants that develop powdery mildew had latent infections, which means that the "healthy" plant you bought was actually infected but had not yet developed symptoms. The reason you didn't notice the infection is that the environmental conditions were not conducive to disease development.

Although rare in houseplants, some of the powdery mildews that infect them produce a resting structure known as cleistothecia. Cleistothecia serve two purposes: They are sexual spores, which means they are the "babies" that resulted when a minimum of two powdery mildews underwent sexual reproduction. Unlike the white, powdery spores, cleistothecia are thick walled and can survive adverse environmental conditions. In the spring, the sexual spores (ascospores) within the cleistothecia are shot into the air and carried by air currents to leaves of other plants. With houseplants, this overwintering stage is of little significance since most homes do not suffer from severe environmental conditions. Depending on the environmental conditions indoors and the health of the plant, the fungus could continue to grow and spread during the entire year.

Managing Powdery Mildew of Houseplants. One of the first things to not do if your plant has powdery mildew is to panic! For most plants, powdery mildew is a cosmetic disease, making the plant look a little ratty, but it will not kill the plant. Houseplant disease management includes gathering up and destroying infected and fallen leaves. If possible, reduce relative humidity around plants, possibly by moving plants out of rooms with high humidity (kitchens and bathrooms).

A final management option is spraying with a fungicide. Before taking this step, try rinsing leaves every few days with a hard spray of water. Many of the fungicides labeled for control of powdery mildew in the home are little more effective than a good, regular blast of water. This may need to be repeated every few days, taking care to not regularly soak plant roots (and possibly causing root rot! We never want the cure to be more fatal than the disease!). Use a product with label directions for use on houseplants. Always read and follow pesticide label directions carefully. Effective fungicides for home use include potassium bicarbonate (Remedy), wettable sulfur, and fungicides containing Neem oil. Although many people swear by spraying a dilute solution of baking soda (Sodium bicarbonate), sodium is very toxic to most plants, and care should be taken to prevent getting this solution on the soil. Wettable sulfur and cycloheximide are known to cause injury to some plants. As always, check the label for directions for the particular plant you are treating. Labels are history-if a chemical is contraindicated for a certain plant, you can be certain that someone had a very bad experience using that chemical on the named plants!

Please check out the new diagnostics web pages at:
http://www.extension.umn.edu/projects/yardandgarden/diagnostics/


Four New My Favorite™ Garden Chrysanthemums Available
from information provided by Neil Anderson, Mum Project Leader

L-R Front: 'Twilight Pink', 'White' Middle: 'Yellow' Back: 'Coral' Photo credit:  My FavoriteTM
Four new U of M chrysanthemums are available in garden centers this spring. Joining 'Autumn Red' are 'Twilight Pink', 'Coral', 'White' and 'Yellow Quill'. These are all My Favorite™ series mums, the sucessor to the Maxi-Mums series.

My Favorite™ mums have a lot going for them. They are winter hardy, butterfly attracting, frost tolerant, large, shrub-like plants, that are self-pinching so there's no need for disbudding in the spring.

All of the My Favorite™ series form a large plant. Multiple plants, when planted 1'-2' on form a perfect hedge habit (clipped in appearance without any pruning or shearing) in the second and successive years of growth. Plant habit is a cushion type, producing plants in the garden that are hemispherical in shape with flowers completely covering all exposed surfaces of each plant.

The My Favorite Company is the exclusive licensee with the University of Minnesota to test, propagate, grow, and sell the My Favorite™ garden chrysanthemum cultivars worldwide. To be included in the My Favorite™ brand, each cultivar must have outstanding garden performance and be easy to grow. Visit the company website at http://www.myfavoritegarden.com/ for more information. To see additional photographs, including very large images (so you can see the flowers), click on: http://www.myfavoritegarden.com/about_lib_index.html

Important cultural information. For general mum culture, please see Garden Chrysanthemums at http://www.extension.umn.edu/distribution/horticulture/DG7068.html

Please note that all of these cultivars are protected by US Patents and Plant Breeders Rights (in the rest of the world) and all asexual propagation (cutting, division, etc.) is strictly prohibited.

Winter survival. The My Favorite™ brand of garden chrysanthemums have superior winter hardiness in USDA Z3-10. Many additional factors may occur that can reduce winter survival, including frost heaving, lack of adequate moisture, disease organisms causing crown and rhizome death.

For maximum winter survival in the north, do not cut the plants back in the fall after a freeze. Rather, leave the plant material as this will serve as a natural "snow fence" to protect the plant's crown over the winter as well as serving as a snow fence. Remove the remaining above-ground plant material the following spring prior to shoot emergence of the next year's growth.

In southern regions with warmer climate conditions, My Favorite™ chrysanthemums will overwinter as green plants. They may even flower more than once. Since winter survival is based on minimum cold temperatures, survival is not guaranteed in areas where the winters are moist and heavy clay soil conditions are prevalent.

Photo credit:  My FavoriteTM
Planting times. It is preferable to plant your My Favorite™ chrysanthemums in the spring as small plants. The advantages of spring planting include heeling the plant in and allowing for establishment, flowering, and acclimation to fall/winter seasons the first year. This will greatly increase winter survival. However, it is possible to plant large containers of My Favorite™ mums in the fall months (August - September), provided the soil around each crown is adequately mulched. As with all herbaceous perennials, it is preferable to plant mature, flowering plants in the fall during late August or into the first week of September.

Growing On. Each season of growth should follow the same protocols for culture. My Favorite™ mums are low-maintenance herbaceous perennials. Do not pinch, shear, or hedge-clip the plants during the growing season. They are naturally self-pinching and will attain the cushion plant shape. During flowering, no dead-heading is required either.

My Favorite™ mums have been bred to be disease tolerant. The use of chemicals to control insects or diseases is not required in most circumstances.

Fast Facts: The Five "My FavoritesTM
My Favorite™ 'Autumn Red'
Description:
Maroon single daisy with gold centers (6-9 cm); My Favorite™ 'Autumn Red' has a plant height of 1.8-2' (year 1) and 3-3.75' (years 2 & onwards)
My Favorite™ 'Autumn Red' is a late season flowering plant, typically coming into flower in later September - October in the north. Since its flowers are frost-tolerant, it will continue to flower until a hard freeze has occurred.
My Favorite™ 'Coral'
Description:
Coral, triplex-quadriplex daisy flowers (6 cm) and midseason flowering.
My Favorite™ 'Coral' has a plant height of 1.2-1.6' (first year) and 2.4-2.9' (second year) with a plant spread of >3.5' in the second year of growth. The branching pattern is spreading and very prolific.
My Favorite™ 'White'
Description:
This selection has white semi-double flowers (7 cm) with yellow centers.
My Favorite™ 'White' has a flower color that matches most color plantings in the garden.
My Favorite™ 'White' has a plant height of 1.5-1.6' (first year) and 1.8-2.25' (second year) with a spreading and very prolific branching pattern.
My Favorite™ 'Twilight Pink'
Description:
This is a buffy pink daisy (5 cm dia.) with a bright yellow center and a purple eye. The flower petal colors resemble the sky coloration at twilight.
My Favorite™ 'Twilight Pink' attains a plant height of 1.5-1.75' (first year) and 2.5-4' (second year) with a plant spread of 2.5-5.5' in the second year of growth.
My Favorite™ 'Yellow Quill'
Description:
This is a yellow, single daisy spoon (8 cm) with a yellow center.
My Favorite™ 'Yellow Quill' attains a plant height of 1.5-1.75' (first year) and 2.75-3.5' (second year) with a plant spread of 4-5' in the second year of growth.


Editorial Notes

Nicotianas and St. John's wort. Photo credit:  Beth Jarvis
The nictotania photo was taken in British Columbia last summer. I went for a wedding but managed to see 10 to 12 gardens in the time I was there. (Priorities!)

The snowdrops have been blooming by my house for almost a month. The crocus and squill are in full bloom. A neighbor appears to have daffodils in bloom (spotted it on my drive to work on Apr. 14) but they're right next to the basement wall and on the south side of the house. Some April showers would be very welcome about now.

I'm organizing stories for upcoming issues. Coming soon, we'll have something on landscape design, everything you need to know about plums and plum pollenizers, and an article on climatic changes are changng the ranges of some animals. We're back to twice a month publication, so the deadlines come thick and fast.

Please feel free to cut and paste any of the articles for use in your own newsletters. All we ask is that you give our authors credit.

Back issues Yard & Garden Line News are on the Yard & Garden Line home page at www.extension.umn.edu/yardandgarden/. Our home page has clickable links to most of the components of the Yard & Garden Line, such as Bell Museum of Natural History, INFO U and the Soil Testing Lab.

Deb Brown answers gardening questions on Minnesota Public Radio's (MPR) "Midmorning" program on the first Thursday of every month at 10 a.m. Katherine Lanpher hosts the program that is broadcast on KNOW 91.1 FM, and available state-wide on the MPR news radio stations.

If you have gardening questions, please call the Yard & Garden Line at (612) 624-4771.

If you would like to receive an e-mail reminder when the next issue of the Yard & Garden Line News is posted to the web, just send an e-mail to: listserv@lists.umn.edu (note: the second E in listserve is omitted), leave the subject line blank, then in the body of the message, type: sub yglnewslist or to unsubscribe, enter: unsub yglnewslist

Happy gardening!

Beth Jarvis
Yard & Garden Line Project Coordinator


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