Monday, May 16, 2016

2015-16 Cool Season Trials Yield Top Picks for Off Season Color

Posted by James E. Klett, Professor, Colorado State University, Department of Horticulture and Landscape Architecture.

One hundred and sixteen varieties were evaluated in the 2015-16 Cool Season Trials from planting in mid-October 2015 through April 2016. At the end of the observations, eight plants were selected by the Annual Trial Garden Committee as top-rated performers. All varieties were monitored and observed weekly during the trial period. Plants were watered when the soil was dry and the temperature above 40 degrees Fahrenheit, but we had good snow cover for about two months of the trial period.  The eight winners are listed below.

Best of Show Pansy
Cool Wave® Frost from Pan American. This is a spreading type of pansy and would be excellent for hanging baskets. This variety had good flower cover producing many blooms in a multi-color pastel blue and white.

Best Blue/Violet Pansy
Inspire® Plus Marina from Benary. This pansy had a soft blue color with a contrasting eye of golden yellow. This is a traditional more upright type pansy with a very uniform habit with short pedicels and upward facing flowers.

Best Yellow Pansy
Freefall® Golden Yellow from Flora Nova. This is again a spreading variety that would be excellent for baskets. The flowers are a clear golden yellow with prominent darker whiskers in center flower. It again provided excellent flower cover over the entire plant.

Best Orange Pansy
Spring Matrix® Orange Deep from Pan American. This is a new category for 2015-16 since we had a lot of orange pansy entries. It is a traditional more upright growing pansy with deep orange, frilly flowers. This variety overwintered extremely well.

Best Violas
Pan American Seed Company’s Sorbet® XP Series dominated in each of the categories in this year’s cool season trial.

Best of Show and Best Blue Violet Category
Sorbet® XP Beaconsfield Improved won in both of these categories because of its eye-catching bicolor viola with a deep blue/violet center that faded to a lighter blue/violet with a nice bright orange eye. It had excellent flower cover and overall would add great curb appeal.

Best Yellow Viola Category
Sorbet® XP Yellow Blotch from Pan American. The flower color was a deep yellow with a nice chocolate blotch. It had very uniform growth habit with strong flower stems and a very even flower cover.

Best White Viola Category
Sorbet® XP White Blotch. This variety had a very uniform and consistent growth habit with many flowers with very large flowers for a viola. The flower color was white with a bluish blush.

Best Novelty Viola

This is also a new class this year with Sorbet® XP Orange Jump Up winning the honor. Flowers were a stunning contrast of deep violet and vibrant orange and flowers showed no sign of fading.

Thursday, May 12, 2016

Sins of the Landscape

My fellow Horticulture Agents will agree; sometimes it is hard to drive around town and see the landscape “sins” that are going on.  One of our Tri River Area Master Gardeners recently wrote an article on trees.  It pained her to see them improperly planted, pruned or ignored.  Please do your homework.  Plant the right tree in the right place.
Plant using the latest updated planting techniques.
Do your homework before you prune.
If the tree is in the right place, you should have minimal pruning to do.  Always remove dead, dying and disease wood as soon as you see it.  And please never, never top a tree.  Some people will say they are pollarding.  Pollarding is started on saplings and was used in Europe to produce a quick large amount of wood that was then used for firewood.  “Pollarding”, aka topping, should never be done on large trees.  When topping is done, it is committing the tree to a short life.  Talk to your local Masters Gardeners about trees.  They will be happy to fill you in so you can grow trees that live longer than we do.  Leave a Legacy.
Right plant, right place

Now on to the next “sin” I witnessed driving home the other night.  A local business was laying weed fabric.  Well, the big problem with this is they were laying it over already existing fabric and decomposed granite rock.  Then they were putting a 1” or larger river rock on top.  I assume they were doing this to help conquer the weeds.  The problem, actually there is more than one, is first: old fabric gets dirt built up on it and it essentially clogs the pores of the fabric.  This dirt build up on top is why the weeds are now there.  Secondly, one has to understand the movement of water through different materials.  Water moves through one material before it will start to penetrate another layer.  These layers are called interfaces.  So by the time water moves through 4 layers of material how much is going to actually get to the soil below and to the roots of the plant.  The correct thing to do would be to remove the existing rock mulch and fabric and start over.  Or not use fabric to start with and use other methods to control weeds.

Dandelion photo by Susan Carter

Controlling weeds starts by identifying the weeds that you are trying to get rid of. We have winter annual weeds that start growing in late summer or early fall.  These them start growing like mad in early spring and are already setting seed at lower elevations.  Downey Brome, aka Cheatgrass, is one great example of a winter annual.  Then we have annuals that germinate in spring or summer.  Biennials type of weeds grow vegetation one year and bloom and go to seed the second year.  And perennial weeds are ones that will come up at least 2 years or more from the root system.  Woody weeds fit in this category.  Pre-emergents can be used to control weeds in areas like the rock mulch bed in my story, but it is important to know the identity of the weed or its life cycle so you apply the herbicide at the appropriate time.  Of course, manual removal of the weeds is one way to control them.  Spraying herbicide on them after they have germinated is another and trying to out compete them with properly grown turfgrass or cover crops is another. (Always read the label and follow instructions on pesticide labels.)
Feel free to take weed samples to your local Extension office.  Please bring the entire plant and if it is blooming, that is even better.  The more information we have, the better we can help you.  So do your homework, choose what works best for you and your landscape, to help you maintain a healthy landscape.   Blog posted by Susan L Carter, Horticulture Agent, CSU Extension Tri River Area

Tuesday, May 10, 2016

Spring Storms Damage Trees

By: Mary Small, CSU Extension, Jefferson County

Ouch! Our spring snowstorms have wreaked havoc on our trees and shrubs. Poor things, they have such a challenge growing in our climate to begin with, and then this: two snow events that snapped off branches and damaged some trees beyond repair.  My colleagues and I have been inundated with questions about how to handle these issues.

Cut back to branch collar 
The quick answer is it depends on the damage and the health of the tree. In this first photo, the branch should be removed back to the branch collar –which is the trunk in this case. Don’t just cut off the broken and split branch and leave a stub! Removing branches may make the tree look a bit bare (and maybe even odd!), but eventually the new leaves and branches will mask the damage.

Root breakage 
The pine tree was essentially tipped over and pulled out of the ground from the weight of snow on its branches, resulting in a lot of root breakage.  It’s best to remove this tree.

Lost leader
Some trees lost their leader. Tree owners can just let nature take its course;  the tree will develop a new leader from a side branch nearest the injury. They can also attach a stake to the top of the main stem and select a branch to take over as leader. The branch is bent upward (don't crack or break it!) and tied to the stake.

Honeysuckle - in the
In cases like this honeysuckle, where the branch broke off, the best course of action is to make the edges of the wound neat and clean, using a knife to remove and smooth the jagged edges.

 1st place for most creative "fix"!

I found this very creative (although ineffective) broken branch treatment in my neighborhood.  I’ll watch it over the next year or two and report back on its progress – or lack thereof!

Monday, May 9, 2016

The Answer: Iris "Accordians"

Posted by: Alison O'Connor, Larimer County Extension

Thanks for you comments...I laughed at the response that the plant didn't wear sunscreen (a good reminder to all of us!) and Dr. Steve Newman said a fellow Twitter follower said it was a result of listening to Lawrence Welk music.

My best guess...which was supported by fellow CO-Horts Mary Small and Tony that it's most likely freeze/chilling injury. Since it was the third leaf on both sets of plants, it led me to believe that these plants were damaged either in the bud or as they were emerging. The plants are located close to the home and are always early to emerge, so it was likely during one of those cold snaps we experienced in late March or early April. Also the leaves were likely constricted during emergence, which led to the accordian-fold.

But if anyone has any other thoughts or reasons as to how this may have occurred, I'd love to hear (and be corrected).

Thursday, May 5, 2016

Iris "accordians": What caused it?

Posted by: Alison O'Connor, Larimer County Extension

As I was mulching my front yard a couple weekends ago, I noticed this funny growth pattern on my iris. But it was only on a couple of the leaves....specifically, the third oldest leaf on each plant. Both plants are near my west-facing front door.

Iris "wrinkles"
What do you think caused this? No Googling!

Iris "elastic bands"
In a few days, I'll post (what I think is) the answer. Submit your comments below!

Friday, April 29, 2016

Turf mite injury

Posted by Robert Cox, CSU Extension - Arapahoe County

So when we have long-lasting snow cover in the winter, we get vole damage and snow molds in our lawns, especially on north and east exposures.   During winters with very little snow cover, we get mite damage to lawns, especially on south and west exposures.

Winter 2015-2016 gave us some of each; see Dr. Tony Koski’s post about vole injury and snow molds March 14, 2016.

Following Jimmy Buffet/Alan Jackson 5 o' clock logic, one could argue that some turf mite injury to lawns - somewhere along the Front Range - could occur just about every winter.         Here in Arapahoe County, it seems that most winter turf mite injury seems to be caused by Banks grass mites rather than clover mites.  This could be in part due to our county politicians’ 2012 ban on clover mites.

Banks grass mites are a little bit like us – they want to reproduce, hang out with the kids, contribute to their 401k, and spend a few winter vacation days in a warm dry spot.   While they can’t get $79 Southwest airfares to San Diego or Phoenix in March, they can choose to thrive and proliferate in the warmest and driest portions of our lawns – on Southwest exposures, especially on slopes.   If these exposures are near the house, rocked landscaping or evergreens, it really adds to the ambiance.

Preventing or minimizing mite injury involves sprinkling prone turfgrass during warm, dry snowless periods – mites dislike water.  Or - miticide application to prone turf areas.   More details at

To renovate or re-sod large dead areas, see more detail at

Here are a few photos of mite injury to turfgrass - often matted and killed.   All are located on South or West exposures.  Can you name the other factors in each photo that contributed to mite injury?

Thursday, April 28, 2016

Hate vegetables? Or don't have space for a large garden? Try this.....

                                          Photo credit: the
                                          By Linda Langelo, CSU Horticulture Program Associate

Micro greens are the young “seedlings” of any vegetable which are harvested at either the cotyledon and/or first-true-leaf stage of their growth.  The cotyledon are the first leaves that appear after germination once the plant has established its root system.  As the plant continues growing, it sends out leaves which take a distinct shape.  One plant is distinguished between another.  These leaves are called “True Leaves”.   The plant continues growing for one to two weeks and they are called micro greens.  Once past the micro green stage, they are considered baby greens-like spring mix.    

Micro greens are another source of fresh food.  If you don’t like eating a particular vegetable like beets, try beet micro greens.  In ten to fifteen days, you can harvest many different choices of vegetable micro greens.  You can also grow herbs as micro greens but this will take longer than 15 days and up to 25 days or more.  Think of planting a flat of seed of red cabbage and then harvesting the leaves within fifteen days and enjoying a nice mild flavor of the seedling’s leaves.  These seedlings do contain a lot of nutrition, but I am not a doctor, just a gardener.  So do have a discussion with your doctor if you want to use these for supplemental nutrients.  I am just suggesting this might be a way of having a larger palette of greens with a wide array of flavors.

Micro greens can be used as garnish, in soups or salads, for juicing, added to your sandwich and yes, even stir-fried.  For some, this may be a way of gardening because of lack of proper outdoor space or location.  For others, this may be a way of satisfying their need to garden during the winter or during the season because of their busy lifestyle, age or disability.   You can add containers to your kitchen counter or windowsill and within a couple of weeks be enjoying the “fruits of your labor” without much labor.  A windowsill with eastern, western or southern exposure will work.  It is best if the micro greens get up to 4 hours of sunlight.  If not you might want to think about supplemental lighting.
                                                             Photo credit:
My favorite is sunflower micro greens with their nutty flavor.  Pea shoots are another favorite of mine which taste like peas without eating peas. Both sunflower and peas as micro greens, you can only take one cutting.  You can take any vegetable seed and grow it in a flat.  Cover the flat with seed; spacing the seed from ¼ to ½ inch apart and cover lightly with the soil mix.  Then make sure the seeds have a soil temperature of 75 degree Fahrenheit.  Once they germinate, reduce the temperature to 60 degree Fahrenheit for the soil temperature.  Keep the sowing mix moist at all times by watering from the bottom and not splashing water on the leaves of the seedlings.  These seedlings have such a short-life span that they rarely acquire any diseases or pests.  You can reuse the flat if you choose.  After cutting the stems of the current micro greens in the flat, leave the roots and plant more seed on top of the soil and lightly cover again with soil. 
For fertilizing your seedlings, you can start out with fertilizer in the soil mix or you can add fertilizer when watering, also from the bottom. 
When you are thinking about choosing micro greens to grow together in a flat, be sure they all have the same or similar growth rates.  All fast-growing varieties should be sown in separate rows or sections in the same flat as you would sow all slow-growing varieties in separate rows or sections in the same flat.  You could just grow one variety, if you end up picking a favorite you could not live without. 
If you are thinking of using just one flat for your favorite micro greens, you can divide the flat into sections.   As many sections as you like.  For fast-growing vegetable seedlings you could plant separate sections of red cabbage, radishes, mustard and kale.  For slow-growing vegetable seedlings which take from 16-25 days, you could plant separate sections for beet, chard, carrot and amaranth.  For herbs there are slow-growing choices such as fennel, basil, cilantro, parsley, dill, shiso, sorrel and salad burnet.
                                              Photo credit: Linda Langelo, Will Allen's Growing Power,
                                              Pea shoots in flats lining the bench.