Walt Disney wanted his productions to register with as many of our sensory tracking systems as possible. This became the verb, 5–sense. Have you 5-sensed a product or considered how the product registers on each of your five senses? Consider a romantic dinner setting and how it addresses the sights, sounds, tastes, touches, and smells (5-senses) of the surroundings. Applying this concept to our gardens, how might we 5-sense a garden?
One approach is to consider the possibilities available from a number of plants with short stature and a creeping habit (Table 1). Although collectively described as groundcovers, these plants accomplish so much more then simply covering the ground. A garden gains charm and a nuanced complexity when a “creeper” is nestled into small spaces, fills a barren crevasse, or spills over a wall or slope.
Pay attention to the location needs of each plant. Charm turns quickly to disappointment when a misplaced plant languishes in a location to which it is not adapted. Keep the soil moist for at least a week to ten days following planting and water regularly until the plants are well established. Many of these plants have low water requirements and once established are robust and forgiving to occasional neglect. Most flourish in partial to full sun exposures, while a few can tolerate full shade.
Having addressed and managed the horticulture part of the equation, how can we now tap the creative and 5-sense with creepers?
Fragrant pathways and patios
Consider the charm of a path or patio that greets its visitors with the fragrance of thyme. Placing creeping herbs between patio or path stones can add a sensory dimension to the garden. Stones can protect the plant and provide a surface to crush wandering stems, thus releasing their natural or essential oils which are aromatic compounds. These compounds are volatile and are released in a sufficiently high concentration to activate olfactory receptors in the upper part of the nose. Leaves of plants such as basil and thyme carry such oils, as do the flowers from chamomile and jasmine.
There are a number of creeping thymes (Thymus sp.) that survive in our climate and deliver fragrance. Be adventurous and take your shoes off as you walk on the path to add to the tactile quality of the experience. Other fragrant alternatives include Corsican mint (Mentha requienii) or chamomile (Anthemis sp.) if you are willing to accept the fact that these plants typically function as annuals in Minnesota. Non-fragrant creepers such as Sagina Irish moss or Veronica liwanenss Turkish speedwell can also add great character to a path. How much have the stairs illustrated been upgraded by the addition of Scotch Moss (Sagina sp.)?
Cascading and creeping effects
The short stature and a strong crawling habit of our creepers permit garden metaphor. Placement of creepers in rock gardens and proximal to walls captures the flowing habit of their growth pattern. These plants literally spill through openings and flow over walls; the analogy to streams and rivers is inescapable. Consider the water-like effect of thyme or creeping phlox (Phlox subulata) as it creeps between rocks or cascades over a small rock wall. Skip the trip to New York, bring the Niagara River to your backyard. Can you not hear the water and feel the spray?
|Table 1. Some “creepers” with proven zone 4 hardiness.|
|Achillea tomentosa Lemon "Dwarf Woolly Yarrow"||L||Adaptable||Part to full sun||Moderate|
|Arabis sturii "Mountain Rockcress"||N||Adaptable||Part to full sun||Light|
|Carex speciosa Velebit Humilus "Sedge"||N||Adaptable||Part sun to full shade||Light|
|Erigeron scopulinus "Sunny Side Up Fleabane"||L||Sandy||Part to full sun||Moderate|
|Erysimum kotschyanum "Dwarf Yellow Wallflower"||L||Adaptable||Part to full sun||Light|
|Erysimum kotschyanum "Orange Flame"||L||Clay||Part to full sun||Light|
|Houstonia caerula "Bluets"||N||Adaptable||Part sun||Light|
|Lysimachia nummularia aurea "Golden Creeping Jenny"||N||Adaptable||Part sun to full shade||Moderate|
|Lysimachia nummularia "Creeping Jenny"||N||Adaptable||Part sun to full shade||Moderate|
|Mazus reptans alba "White Mazus"||N||Adaptable||Part to full sun||Moderate|
|Mazus reptans"Purple Mazus"||N||Adaptable||Part to full sun||Moderate|
|Mazus radicans "Motley Mazus"||N||Adaptable||Part to full sun||Heavy|
|Persicaria affinis "Himalayan Border Jewel"||N||Adaptable||Part to full sun||Light|
|Potentilla reptans "Pleniflora"||N||Adaptable||Part to full sun||Moderate|
|Potentilla cranztii "Pygmaea"||L||Adaptable||Part to full sun||Light|
|Sagina subulata aurea "Scotch Moss"||L||Adaptable||Part sun||Heavy|
|Sagina subulata "Irish Moss"||N||Adaptable||Part sun||Heavy|
|Sedum album chloroticum "Baby Tears"||L||Adaptable||Part to full sun||Light|
|Sedum acre "Goldmoss Stonecrop"||L||Adaptable||Part to full sun||Moderate|
|Sedum spurium "John Creech"||L||Clay||Part to full sun||Moderate|
|Sedum humifusum "Dwarf Stonecrop"||L||Adaptable||Part to full sun||Moderate|
|Sedum lydium "Mossy Stonecrop"||L||Adaptable||Part to full sun||Light|
|Sedum requieni "Miniature Stonecrop"||L||Adaptable||Part to full sun||Heavy|
|Silene acaulis "Moss Campion"||L||Adaptable||Part to full sun||Moderate|
|Stachys densiflora "Alba"||N||Adaptable||Part to full sun||Moderate|
|Thymus praecox "Pink Chintz"||L||Sandy||Part to full sun||Moderate|
|Thymus praecox "Bressingham”||L||Sandy||Part to full sun||Moderate|
|Thymus serpyllum "Miniature Thyme”||L||Adaptable||Part to full sun||Heavy|
|Thymus praecox "Highland Cream"||L||Sandy||Part to full sun||Moderate|
|Thymus praecox coccineus "Red Creeping Thyme"||L||Adaptable||Part to full sun||Moderate|
|Thymus praecox albiflorus "White Creeping Thyme"||L||Adaptable||Part to full sun||Moderate|
|Trifolium repens atropurpureum "Bronze Dutch Clover"||N||Adaptable||Part sun||Moderate|
|Veronica oltensis "Miniature Speedwell"||L||Clay||Part to full sun||Moderate|
|Veronica allionii "Alpine Speedwell"||N||Adaptable||Part to full sun||Moderate|
|Veronica repens "Golden Creeping Speedwell"||L||Adaptable||Part sun to full shade||Moderate|
|Veronica stelleri "Manns Variety"||N||Adaptable||Part to full sun||Moderate|
|Veronica liwanensis "Turkish Veronica"||L||Sandy||Part to full sun||Light|
|Veronica repens "Creeping Speedwell"||N||Adaptable||Part sun to full shade||Moderate|
|Veronica surculosa "Waterperry Blue"||L||Adaptable||Part to full sun||Moderate|
|1. Water needs: L = Low, N = Normal|
|2. Traffic = 1 - 2 times weekly; Moderate = 1 - 2 times daily; Heavy = 3 or more times daily|
|Note: Information adapted from www.stepables.com|
Heliopsis helianthoides (common names: heliopsis, false sunflower, sunflower heliopsis, and smooth oxeye) have recently come into bloom in Minnesota. This attractive plant is native to the prairies of Canada and the Eastern and Central United States (cold hardiness zones 3-9). Its combination of drought-tolerance, pest resistance, and long bloom season (in most years June-August/September) make it an excellent choice for perennial gardens and wildflower plantings. Clump forming plants (~2-5’ tall) commonly produce golden-yellow daisy flowers (~2-4” in diameter). After the first or primary flower head opens (at the top of the stem) there is the potential for the development of multiple side branches generating additional flower heads if growing conditions are favorable. Well-grown plants can remain in flower all summer long- even without deadheading! Plants prefer full sun and well-drained, moderately fertile soils.
Although a North American native, its popularity in gardening circles first soared the middle of last century in especially Europe. As breeding work resulted in improved cultivars from work done in especially Germany, the excitement for this species spread around the world. American gardeners recognized more clearly the value of this native plant. Sometimes it is easy to take for granted and not see the potential in the native plants we routinely encounter. The vision and effort of individuals in other nations has also been important to significantly fuel the widespread commercialization of some of our other North American native prairie species as well, including blazing star (Liatris sp.).
Heliopsis reliably flowers from seed the first growing season if seedlings are not overly stressed from lack of moisture, nutrients, or light. In addition, seedlings can be germinated in late summer and flower reliably the next growing season. Superior individuals have also been selected and clonally propagated by cuttings or crown division to preserve their unique features.
Although generally pest-resistant, aphids and powdery mildew are known to periodically attack heliopsis. When aphids (typically red aphids; Dactynotus sp.) are present they usually colonize the more succulent, younger stem tissue near the extremities of the plant. Under favorable conditions reseeding may occur and can become a nuisance in some situations.
Recent cultivars with new flower and leaf colors or compact plant habit are making heliopsis more versatile than ever. Below are some popular, widely available cultivars at Minnesota garden centers. Because of their long season of bloom, some nurseries are even selling some of the more compact heliopsis as an alternative for use in planters, a niche typically filled by annual plants.
‘Summer Nights’- Plants are tall (~3-4’) and possess single flowers with mahogany centers (disk florets) and golden petals. Some individuals produce flowers with a mahogany petal base when first open and then the mahogany color on the petals faces fades.
‘Summer Sun’ (= ‘Sommersonne’; German bred)- The oldest of these five cultivars and the one most commonly available. Plants are vigorous and attain ~3’ in height. Although originally selected to be uniform for double flowers, seed lots sold today have often not been carefully managed and frequently segregate for single, semi-double, and double-flowered individuals.
‘Loraine Sunshine’ (Plant Patent 10,690)- Variegated foliage makes this 2.5-3’ tall plant with single yellow flowers very unique. The variegation pattern is dramatic as the leaf veins remain green while the interveinal regions are white. If plants become stressed, the variegation can become less pronounced. During the subsequent growing season new shoots will again be strongly variegated. It was discovered in Wisconsin and has earned the designation of being a Minnesota Tough and TerrificTM perennial (www.florifacts.umn.edu).
‘Prairie Sunset’ (Plant Patent 13,379)- The tallest heliopsis cultivar of the group reaching ~4-5’ tall. Single flowers have a pronounced wine-red petal base that typically lasts longer than ‘Summer Nights’ before fading. Purple stems and dark-green to purple-green foliage provide a dramatic backdrop to the flowers.
‘Tuscan Sun’ (Plant Patent 18,763)- This recent Wisconsin-bred cultivar has the most compact plant habit of any heliopsis (~20”). Plants are well-branched and produce single, golden-yellow flowers.
‘What’s wrong with my plant?!’ Like all living creatures, plants get sick too. So when your begonia breaks out in spots and your tomatoes are soft with rot, it is time to talk to the plant doctor. Plant Pathologists (Plant Doctors) are coming from across the world for their national meeting held in Minnesota this year!
Meet the Plant Doctor is a unique public outreach event that allows you to learn more about plant diseases that you might find in your yard and garden, and to bring your questions to these visiting scientists. Come to the Minnesota Arboretum for a unique opportunity to meet with real plant doctors (plant pathologists) and learn the best strategies for keeping your garden healthy.
When: 10 am – 3 pm, Saturday July 26th 2008
Where: The Minnesota Arboretum
3675 Arboretum Drive, Chaska, MN 55318
Educational Fair (10 am-3 pm)
Come see examples of common diseases of trees, flowers, fruits, vegetables and other garden plants. Learn how to identify what’s gone wrong with your plant and learn what to do about it. Take a closer look at wiggling nematodes, colorful fungi, and the many rings, spots and streaks of virus infected plants. Ask questions about how to care for your garden plants.
Growing a Healthy Garden Tour (10 am – 3 pm)
As you visit the many different gardens on the arboretum grounds learn how to grow a healthy garden. Guides will teach you how to recognize common diseases that could be a problem in each garden. They will explain the best way to avoid disease problems, and will teach you which diseases can be tolerated, and which should be treated.
Doctor’s Advice (11 am – Noon)
Come hear what the University of Minnesota Plant Doctors have to say about taking care of the plants in your garden. Learn what a plant doctor is and what they do. Hear how plant doctors make a diagnosis. Find out more about plant diseases that might occur in your backyard and the best ways to manage them.
Meet the Plant Doctor (1-2:30 pm)
Plant Pathologists from all across the country have come to Minnesota for the annual meeting of the American Phytopathological Society. Here’s your chance to ask questions about dealing with plant problems and growing a healthy garden. Bring samples from your sick plants or photos of the problem. Hear what other gardeners are concerned about and learn how to keep your plants happy and healthy.
This event is free with admission to the Minnesota Arboretum. Please preregister for the Doctor’s Advice and Meet the Plant Doctor sessions by calling 952-443-1422 (this is only to make sure we set up enough chairs, walk-ins are also welcome. Preregistration is much appreciated!). Bring your family!
Come to learn about plant diseases. Go home with a prescription for a healthy yard and garden.
Sponsored by the American Phytopathological Society, the Minnesota Arboretum, and University of Minnesota Extension.
The Lyndale Park Rose Garden will mark its 100th birthday on Sunday, July 27, with a variety of free activities for the entire family from noon-7 p.m. The garden is the second oldest public rose garden in the United States and showcases 3,000 roses in over 200 different varieties. Located near the northeast corner of Lake Harriet in southwest Minneapolis, the rose garden was designed by Minneapolis Park and Recreation Board Superintendent Theodore Wirth and constructed in 1907-08. The basic garden design consisting of 62 rectangular beds with additional plantings along the perimeter has been maintained all these years. When the roses are in full flower there are over 50,000 blooms present! The oldest public rose garden in the nation, located in Hartford, CT, was also designed by Wirth and was constructed in 1903-04 during his park tenure there as head of Connecticut’s park system.
The Lyndale Park Rose Garden is an official test site for the All-America Rose Selection (AARS) award and has been since 1946, when it was inducted as the most northern test site. In 2005 the Virginia Clemons Rose Garden in St. Cloud was added as an official test site and is now the most northern test site. Each year over 50 varieties of new roses bred in the US and around the world are entered into the trials. They are evaluated over two growing seasons and in the end between one and four typically earn the highly regarded award.
The anniversary celebration features a wide variety of music from 1-7 p.m. spanning the last century, such as the “Hokie Pokie” with The Percolators, guitar/harmonica blues and country specialties of Blue Stratum, and ballads like the “Red River Valley” with the Goat Busters. Twin Cities Show Chorus will lead a Community Sing-a-long at 6 p.m. to conclude the event.
Tours of the gardens will be available from noon-4 p.m. Storytelling will occur in the Peace Garden at 1 and 2 p.m. Naturalists will have a Touch and See table set up for children to learn more about birds and wildlife. The Minneapolis Institute of Arts will have an Art in the Park interactive table for art projects. Guests are invited to wear vintage clothing.
Vendors will offer food options from the past century, including kosher beef hot dogs, peanuts, crackerjacks, popcorn, lemonade and cookies.
The Lyndale Park Rose Garden is located at 4124 Roseway Road in Minneapolis. Roseway Road at King’s Highway will be closed during the event. Access the rose garden parking lot from Lake Harriet Parkway. Additional parking is available at Lakewood Cemetery. Enter the gate at W. 40th St. and King’s Highway (Dupont Ave. S) then walk a short distance to the park.
Over the years other gardens have been added to the Lyndale Park complex. This year also marks the 25th anniversary of the nearby Peace Garden, the 45th anniversary of the formal gardens between the fountains and the 85th anniversary of the Border Garden.
Many people have been commonly encountering large spiders in and around their homes lately. In nearly all cases they have turned out to be fishing spiders. Fishing spiders have a body length up to one inch and a legspan of several inches long. They are brownish with banded legs and have eight eyes like most spiders. They are the biggest spider in Minnesota.
Although they are an imposing-look spider, they are essentially harmless to people. They are not aggressive to people and will only bite under duress or if they feel threatened. Even then, a bite is no more painful than a mild bee sting. As the name suggests, they are associated with water but they can range away from this environment. When they enter homes, it is by accident - they would much rather be outside. The only necessary control is to capture a fishing spider (put a jar or similar container over it and slide a piece of paper underneath of it, trapping the spider inside) and release it outdoors.
The hot, dry summer we have experienced so far has been conducive to spider mite infestations. These pests are found on a wide variety of plants including arborvitae, spruce, ash, rose, and beans. They are very tiny, about 1/50 inch long, and yellowish. They use piercing-sucking mouthparts to feed on leaves (on the underside) and needles which results in a whitish or yellowish stippled, speckled look to individual leaves or needles and an overall bronzed or yellowed discoloration to the plant. Webbing indicates a spider mite infestation. Severe feeding can stunt the plant's growth and can even kill the plant.
If you find discolored leaves and suspect spider mites, hold a white sheet of paper or paper plate under the leaves and shake the branch or leaves. If mites are present, you will find tiny spider-like creatures drop down and move around on the paper
Keep plants well watered to reduce their susceptibility to spider mites. You can take a hose and spray infested leaves and needles to dislodge some of the spider mites. If you want to treat your plants, consider applying insecticidal soap or horticultural oil. Although they are only moderately effective against mites, they are 'soft' on natural enemies and helps preserve any predators or parasites that are present. The product must directly contact the mites to kill them and repeated treatments may be necessary.
Residual miticides are not widely available to the general public. Effective active ingredients include bifenthrin, deltamethrin, and lambda cyhalothrin. Read the label carefully to be sure the plant you want to treat is listed for the product you intend to use and follow all label instructions.
Watch for both adult Colorado potato beetles and their hump-backed reddish larvae. By now their stages overlap so you can find adults and all sizes of larvae at any given time. Potatoes are particularly vulnerable to feeding damage when tubers form, generally soon after potatoes flower. Even small amounts of defoliation (as little as 10%) cause potatoes to put energy into the leaves instead of tubers.
Keep your potatoes well watered so they are better able to tolerate feeding damage. If your garden isn’t too large, you can hand pick beetles and larvae, throwing them into a pail of soapy water to kill them. Also crush any eggs you find (they are orange and in clusters on the bottom of the leaves).
An effective insecticide in the past has been Bacillus thuringiensis var. tenebrionis, a bacterial insecticide, but it appears to not be widely available anymore. It was effective against young larvae but not on older larvae or adults. There are other Colorado Potato Beetle control products that contain spinosad. Spinosad is a biorational product that is generally good against chewing insects and should work well against Colorado potato beetles. Another effective biorational product is azidirachtin, sold by a number of different chemical companies. It can be effective but has a short residual.
Most traditional insecticides, such as carbaryl (Sevin) and malathion, are not effective anymore on Colorado potato beetles because of problems with resistance. It is recommended that one does not use these older insecticides. There is at least one newer product, esfenvalerate, available to the general public that should still be effective against Colorado potato beetles in home gardens and is sold under a number of commercial brand names.
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David C. Zlesak, Ph.D.