The CSU garden is complete with signage, and ready to help educate consumers! One garden, devoted to new, and smart plant choices highlights the Plant Select program, and shows a few of the new winners from the 2014 CSU annuals trials. The benefit of these plant choices are that they are proven by research to not only survive, but thrive in Colorado’s tough landscape environment with minimal inputs. These beautiful perennials and annuals will be in your local garden center this spring. Our good/poor landscape management choices gardens include research-based recommendations for proper homeowner care of turf and and other landscape plants. The plant diversity quadrant focuses on showcasing beautiful alternative tree choices to ash. And, what we expect to be one of the most popular garden quadrants contains a wealth of information gathered from the Colorado Department of Agriculture and CSU about the current threat of the Emerald Ash Borer to our urban and suburban forests. 20 Master Gardeners and CSU staff worked 2.5 long days installing the garden to showcase the educational themes. Be sure and visit the Colorado Garden and Home Show running from February 7-15, 2015 at the Colorado Convention Center. Your garden will thank you!
Colorado Garden and Home Show
One of the activities I enjoy most as a Master Gardener volunteer is the annual Colorado Garden and Home Show. Every year, the CSU Extension staff work with Master Gardeners to design the Education Garden at the show, which is designed to provide homeowners with research-based information about gardening in Colorado. This year, I was so privileged to help design the garden with good friend, and fellow Master Gardener, Martha Kirk, under the direction of James Klett, Ph.D. Our theme is Proven Solutions for Colorado Landscapes, and we’re covering a lot of ground with this one! We have 6 different gardens within the space, and we will address Tree Diversity, Small Space Gardening, Emerald Ash Borer, Common Turf and Landscape Maintenance Problems, and we will feature Plant Select plants as well as winners from the CSU Annuals Trials. There are a lot of learning opportunities packed into this 30’x50′ space. Tomorrow, we add all the color with blooming annuals and perennials. More to follow!
Emerald Ash Borer update
This is one of the best summaries I have read regarding this new pest in Colorado. Please click here to review the article by Susan Clotfelter in the Denver Post.
We are at the beginning stages of dealing with the challenges of this pest in Colorado, and many of us will have to make some choices about the ash trees in our landscapes in the future. For now, if you are not in the immediate quarantine, or adjacent area, you probably do not have to make any decisions about your ash trees. However, it is time to become familiar with EAB, and it’s potential for destruction. Consult a qualified arborist if you have concerns about this or the health of any of your trees.
If you are considering planting new trees in your landscape, it’s time to consider alternate species. Please consult this list compiled by CSU. Diversification of our urban forests is a good idea. This list has some terrific trees that are currently underused. I would love to hear which ones are your favorites.
Adversity can be a good thing
No doubt you have read or seen some information on Impatiens Downy Mildew, the newest fungal disease to hit our front range gardens in a substantial way. It’s a new adversity to deal with in our challenging garden environment. Like most pathogens, Impatiens Downy Mildew attacks a specific species, impatiens walleriana, and is characterized by downy growth on the underside of the leaves. This low-growing multifloral annual plant is a workhorse in our shade gardens.
Because the disease requires specific environmental conditions to develop and spread, most experienced horticulturists and nurserymen never thought the disease would arrive in the arid west. However, our unusually cool moist spring coupled with nighttime overhead irrigation helped increase the spread of the spores responsible for the disease.
The disease was first reported in the UK in 2003, and was found in US greenhouse production in 2004. Reports of its spread in the landscape included many eastern and midwestern states in the US, as well as in the provinces of Manitoba and Quebec, Canada.
The disease is not curbed by cold temperatures. Overwintering spores survive to (5F) USDA Zone 5. A trial conducted by Dr. Aaron Palmateer at the University of Florida in 2012 evaluated the effectiveness of fungicide treatments in both nursery production and the landscape. The evidence from the trial showed that impatiens could be successfully grown in the landscape for 8 weeks if a weekly spray program in the nursery was followed by a granular soil application prior to planting, along with a monthly rotation of fungicide sprays. Ann Chase, Ph.D, of Chase Agricultural Consulting also recommended to skip planting impatiens for one year in a bed that was previously infected.
What does this mean for our shade landscapes in the future? While impatiens may be available for purchase in limited quantities, the cost to maintain this plant, because of the recommended fungicide treatments, might exceed its desirability. For now, change is a good thing. Begonias, coleus, and lobelia are great colorful substitutes for shade planting. The New Guinea impatiens, and SunPatiens have been shown to be disease resistant, and are excellent substitutes for impatiens walleriana. It is likely that nursery production of regular impatiens will be reduced next year,and the following years. It’s a great opportunity to shake up your landscape design, and try something new. Plant diversity is a good thing.