CO-Horts Blog

Wednesday, October 31, 2018

2018 “Best Of Winners” from CSU Annual Flower Trials

Posted by:  Jim Klett, Professor, Department of Horticulture and L.A., Colorado State University

The following are some of our “Best Of” winners from the 2018 trials.  The complete list with photos can be found on our website 

Best of Show – Salvia ‘Big Blue’ from PanAmerican Seed 
A later bloomer that is worth the wait was impressive with large flower spikes that are showy in the garden as well as making a good cut flower.  Plants had dark green foliage, strong upright growth habit, excellent branching and very uniform overall.  A strong favorite with bees as well as humans.

Best Novelty - Artemisia ‘MAKANA™ Silver’ from TerraNova
This fine textured foliage plant makes a great complement to many other plants in a classic border.  The beautiful silver foliage is dense on vigorous and very compact and uniform plants.    It would look great in both a container as well as ground.  It makes a good filler plant as well adding a strong textural element to any garden.

Best New Variety – Rudbeckia ‘Rising Sun® AS Chestnut Gold’ from Green Fuse Botanicals
Huge flowers covered this plant all season creating impressive flower power.  Besides the prolific flowering, the intense coloring of the flowers make this a definite “55 MPH plant”.  It is impossible not to be impressed even from a brief glance at a great distance. 


Begonia semperflorens (Shade) - 'Megawatt™ Pink Bronze Leaf’ from PanAmerican Seed
The vigorous plants were characterized by their large leaves, strong stems and large flowers.  The bright pink flowers were very floriferous and had excellent contrast with the dark foliage.  Blooms were self-cleaning so the plants always looked fresh.

Celosia – ‘Kelos® Fire Scarlet’ from Beekenkamp
The attractive dark foliage was impressive all by itself but the abundant petite flowers were bright and made a great contrast with the foliage.  Plants are vigorous and have good garden performance.

Coleus – ‘FlameThrower™ Serrano’ from Ball FloraPlant
The attractive dark red foliage had a bright green edge that created a lot of contrast and a bold look.  Leaf shape was also unique and added interest.  Plants did not flower and kept a very uniform appearance all season.

Combination – ‘Kwik Kombos™ Fire and Ice™ Mix’ from Syngenta
Plants created a ball of flowers in a container that had a very high “Wow!” factor.  Colors were vibrant and made an excellent mix.  It was noted that very few combos work with different genera but this is the exception as the bidens, petunia and lobelia were equally represented and none dominated the other.

Dahlia – ‘Temptation Orange’ from Dümmen Orange
The intense dark foliage makes the color of the clear orange flowers really pop out.  The contrast was especially good in full sun and flower color doesn’t fade.  Dark foliage also hides dead heads and requires less maintenance.  Growth habit was very uniform.

Geranium (Zonal) – ‘Brocade Cherry Night’ from Dümmen Orange
Plants were unique with foliage that has a very large zonation with a rich chocolate color.  The dark foliage makes for high contrast with the bright rose-colored flowers.  The tight double flowers have a bit of a multiflora look to them.  Overall the plants were very uniform.

New Guinea Impatiens – ‘Sun Harmony™ Blushing Orchid’ from Danzinger
Plants were both vigorous and very floriferous and made a very colorful container.  The large flowers held up to the sun and had added interest due to the light lavender striping in the petals.  Growth habit was very uniform.

Osteospermum ‘Osticade™ Lemon’ from Danziger
Abundant clear yellow flowers were unusually large and had a deep yellow eye for added interest.  Blooms were consistent all season long and very showy with uniform plants with clean foliage.

Petunia (Spreading) – ‘Supertunia Vista® Bubblegum’ from Proven Winners
This is a multi-year winner from many past trials and is considered to be possibly the best petunia in the last 10 years.  It always has a dependable show of prolific pink flowers with exceptional vigor.

Verbena – ‘Lanai® Upright Twister Watercolor’ from Syngenta
Abundant flowering covered the canopy almost all season with attractive shades of soft lavender that was attractive even as the blooms faded.  Plants had a long lasting flower display and seemed to “bury its dead” blooms under new ones.  Uniform growth habit and lack of any sign of mildew also made this plant a winner.

Vinca – ‘Tattoo™ Papaya’ from PanAmerican Seed
Very unique flower color and abundant blooms were very impressive.  Flowers had a very unusual and beautiful “inky” blush pattern that helped earn the first part of the name, “Tattoo”.  Plants had an upright growth habit and can grow well in full sun or part shade.

Wednesday, October 24, 2018

Uses for Fall Leaves

By: Sherie Caffey, CSU Extension-Pueblo County Horticulture Agent

I don’t know about your neighborhood, but where I live we have fall leaves covering just about every yard right now! What to do with all of them?! Raking them into a pile to jump in sounds fun, or how about filling up a festive yard bag with a Jack O’ Lantern face on it? Or you could do something more useful with them. Believe it or not fall leaves have many beneficial uses in our landscapes.

My neighbor's Sycamores give me lots of fall leaves to use
You can use fall leaves to add organic matter to your garden beds. Adding organic matter will help your soil hold more water and nutrients, and improve the texture. The ideal soil has about 5% organic matter, which is a lot more than most of natural soils contain. Work leaves into the soil in the beds, and moisten it every so often this fall and winter. The microbes in your soil will break those leaves down into organic matter, which will improve your soil’s quality come next spring.

Do you have fall planted bulbs or garlic? Or maybe some perennials you are hoping to over winter? Mulching plants over the winter helps them to survive until next spring. It stabilizes soil moisture and temperature, giving your plants a more stable environment, and protects them from the elements. It will also prevent newly planted bulbs from frost heaving. Fall leaves are a great source of free mulch. Spread a layer roughly 6 inches deep over your bulbs, perennials, trees, and shrubs this fall to protect them.
Free mulch!

My biggest leaf accumulation is in my lawn. The best thing to do with the leaves on your lawn is to mow right over them and leave them on the surface. It’s much easier than raking them plus it’s good for your lawn! They will break down and add organic matter to your turf. They will also prevent weeds and lower the need to fertilize. If you have so many that you can’t see the grass blades, use your mower bag to collect them and store them for future use.
Leaves waiting to be mulched onto my lawn

Finally, fall leaves can be very useful if you have a compost bin at home. They are a great carbon or “brown” material for your compost. Each time you throw in kitchen scraps, throw in a handful of dried leaves as well to keep a good carbon: nitrogen ratio going. Be aware that leaves that were showing any signs of disease should probably not be used around the landscape.

So don't throw those leaves out in the garbage! Find a use for them around your landscape.

Monday, October 22, 2018

Victor Frankenstein should have taken up gardening

Posted by Carol O'Meara, Boulder County Extension

Cue up some Edgar Winter, it’s time celebrate the birthday of one of our most iconic Halloween bad boys: Frankenstein.  Two hundred years ago, Mary Shelly published the story of the reanimated monster that’s shuffled and groaned its way into the pantheon of ghouls that define the season.

Shelley shocked the world with her gothic horror treatise, widely regarded as the first true science fiction novel rather than fantasy, because it drew on scientific concepts of the day.  Pulled together from pieces of cadavers, the monster was reanimated through electricity from lightning.
A sewn-together creation of bits and pieces is nice and all, but gardeners know her tale isn’t as far-fetched as we’re asked to believe.  We’ve been doing this for thousands of years.  We live with creatures grafted together all the time; in fact, we search them out and make them the centerpiece of our landscapes.

Some are subtle; so seamlessly grafted you don’t realize its two different plants put together.  Others show the graft proudly, and gardeners use this to guide them in planting to proper depth.  Grafting provides us with plants that are sturdier, more disease resistant, or smaller than the original.  It’s how we get cultivars of the same fruit on tree after tree in orchards so we can enjoy Honeycrisp apples or Cresthaven peaches. 
In order to make sweet, edible apples one needs to grow the exact cultivar by cloning as grafts on rootstocks. If you try to grow them from seed, you get the result of apple flowers crossing with other, usually crabapples.

It’s also how we have trees sporting several different fruits on the same plant.  Often called “fruit cocktail” or “fruit salad” trees, gardeners with big desires but small space can have it all: with four, five, even six different fruits on a single trunk.  Nectarines, plums, apricots, and peaches or red, green, and yellow apples come together in a fusion of flavor.
Scientists are running wild having successfully grafted fruit trees they’re grafting anything that doesn’t move in the garden: tomatoes, melons, the neighborhood rabbits.  Ok, maybe not the rabbits, but horticulturists are very excited about grafting.

Clones, too, surround us; they give us perfect replicas of plants we covet at other’s homes or businesses. Technically, the definition of plant cloning is human-controlled asexual propagation of a plant, which doesn’t sound fun at all. But we do it all the time.
While Victor Frankenstein raided graveyards for his body bits, we raid plants we see while walking the neighborhood or sitting at the doctor’s office awaiting our turn.  With a quick, surreptitious pinch, we snitch a bit of plant to put in water for rooting, thus cloning the plant.  Love that African violet?  Pinch off a leaf and plant it.  The begonia at an atrium in the mall?  They root nicely from leaves as well (readers: denuding a plant you don’t own is unethical.  Ask permission before taking anything from the plants you see).

When it comes to bringing things back from the dead, gardeners have much in common with Victor; anyone who’s had a jade plant fall and shatter into pieces knows the desire to resurrect it by shoving a bit of stem or leaf into potting mix (the leaves should be dried a bit before doing this, but that’s a different story).  It takes a while for the leaf to root but shocking it with electricity to speed things up would end in disaster.
Ultimately, Victor wasn’t such a bad guy; he simply needed to take up gardening. 

Monday, October 15, 2018

Fall is for Butterflies, too!

Painted Lady on Okra, Photo Credit: Linda Langelo
Fall is a time when color abounds with the changing season and during that same time there are butterfly migrations.  September is a month where Painted Lady and/or Monarchs can be seen in high numbers.  Unfortunately, there high numbers are diminishing.  According to World Wildlife Fund and the Mexican government due to habitat destruction from illegal logging and tourism in the small patches of forests in Mexico where they overwinter.

If you want to see Painted Lady Butterflies and/or Monarchs and others and help with their population numbers, then think about giving them food sources in your landscape.  Monarch caterpillars require milkweed while the adults take nectar from cosmos, Canada thistle, rabbitbrush, zinnias and many more flowers.
Monarch on aster, Photo Credit Linda Langelo

There are several sites you can go to for information on planting the appropriate plants in your region:

  •   National Wildlife Foundation
  •   Biota of North America's North American Plant
  •   USDA's Plant Database
  •  Colorado State University Fact Sheet on Attracting Butterflies to the Garden
If you are anything like me and want to keep the color in your garden going until the very end of the season, below are a couple of ways to join in and help change the habitat for the benefit of Monarchs, Painted Lady Butterflies and many other pollinating insects:

  • Start a Monarch Watch waystation. You can register your garden.  By doing that you receive a sign advertising your garden's friendliness to monarchs.  Then the name of the city and waystation owner will be listed on the program's website.
  • The North American Butterfly Association has certification program that covers habitat requirements for all butterflies.
  • Wild Ones launched a monarch-specific certification program for gardens planted with species native to North America.
  • The Xerces Society has a certification for "pollinator habitat" program.
All are pollinators need more gardens appropriately developed since cities and even small towns create what is called interrupted spaces.  These are places such as asphalted parking lots and areas expanding with newly constructed developments.  Adding a few key plants to your garden can color up your fall garden and benefit your landscape's ecosystem and attract more color through many fascinating pollinators.

Coloring your garden with key plants can make it a local food bank for butterflies, moths and many more pollinators.  According to Karen Oberhauser, a monarch researcher at University of Minnesota along with other scientists, points out that monarchs "are the flagship species. By preserving monarch habitat that includes nectar sources and milkweed, we're going to be helping a lot of other organisms as well."

Overnight guests on a cotoneaster, Photo Credit: Teresa Howes

Monarchs have a fascinating story.  The Monarchs east of the Rocky Mountains migrate to Mexico to the oyamel fir trees.  The Monarchs west of the Rocky Mountains migrate to Southern California.  Monarchs can not tolerate the freezing temperatures of our climate.  By the end of summer the fourth generation of Monarchs migrate back south starting in October or sooner if the weather turns cold.  They migrate north because of the milkweed necessary for the caterpillar stage of their lifecycle.  This is just a brief summary of their very detailed life.

Fall isn't just for the fascinating colors of leaves, it is for the butterflies, too.  And yes, all the other pollinators, too. 

Monday, October 8, 2018

Colorful Colorado - The science behind our fall colors

by Amy Lentz, Weld County Horticulture Agent

Each year, after the summer season ends and ski season begins, there’s a two to three-week window of color that shifts its way across the state of Colorado. During this short period of time, vibrant colors such as red, orange, yellow and purple will brighten up the sometimes-dreary weather, giving us one last show before winter sets in. I was lucky enough this year to experience the fall colors in early September near Walden, in late September near Frisco, and currently along the lower elevations of the northern Front Range.

This year's predictions for aspen fall color across the state, from

Various hues of yellow, orange and red from Aspen trees near Frisco in September.

As you observe these striking changes in the trees, shrubs and grasses in your surrounding landscape, you might wonder “What is the science behind the beauty?

The genetics of the plant are a key factor in what color they will express during the fall season. Certain trees such as poplar, cottonwood, honeylocust and some ash trees will be various shades of yellow, while others such as maple, sumac and some oaks will lean more toward the orange and red tones.
Yellow fall color of a honeylocust tree.
Environmental conditions are another major factor. As the seasons change and we have shorter day lengths and cooler temperatures, a response is triggered in plants to shift their focus toward going dormant. Not only do these environmental conditions switch on the process of leaves changing color, they can also determine the intensity of fall color from year to year. Along with good soil moisture during the growing season, the warm days and cool nights of autumn help to trap sugars in the leaves, making some fall color displays more vivid.

Brilliant fall color in Jackson County near the Wyoming border in early September.

On a microscopic level, it’s the underlying plant pigments that lead us deeper into the science behind these amazing fall colors. So just how does the leaf make these interesting colors?

During the growing season, leaves have been producing the tree's food using chlorophyll, the dominant leaf pigment that is expressed as a green color. The chemical nature of the chlorophyll molecule allows it to absorb sunlight and use the energy to convert carbon dioxide and water to carbohydrates for the plant. Because the plant is actively growing and needs a large amount of food to be produced, chlorophyll is in high abundance and most of the leaves you see are green. Although other plant pigments are present in the leaves, the large amounts of chlorophyll present during the growing season will mask other, less abundant, pigments.  As the season progresses, the leaves will lose chlorophyll as they senesce, revealing our next pigment…

Carotenoids are also pigments made in the chloroplasts of plant cells, however some carotenoids remain in the cells and are unmasked after the chlorophyll degrades. Because these carotenoids absorb blue wavelengths of light, they tend to show up as leaves with a yellow hue.

Carotenoids expressed as yellow tones on a Kentucky coffee tree. 

The other variations of color that we see in fall foliage comes from yet another plant pigment called anthocyanin. This pigment is actually produced in the leaf of some plants prior to leaf senescence (leaf drop). It’s the combination of the anthocyanin and the carotenoids present that give us the other brilliant fall colors of red, orange, brown and purple. Anthocyanins and chlorophyll can produce brownish colors, while anthocyanins and carotenoids produce orange hues. Those leaves that show a red or purple color have a high proportion of anthocyanins.

Red fall color from anthocyanin production on an Autumn Blaze maple tree.

Red fall color of a burning bush, a common landscape shrub.
So, there you have it...some science behind the beautiful colors of the autumn season that we see not only on trees, but also on woody shrubs and ornamental grasses. These amazing fall colors are another reason we call our state 'Colorful Colorado'!

Monday, October 1, 2018

Planting Fall Bulbs for Spring Color

Posted by: Alison O'Connor, Larimer County Extension

I've always dreamed of having a spring landscape filled with daffodils, crocus and tulips--one that made people drive by slowly, admiring the riot of color. I spent a spring in England during my undergraduate degree and their fields of daffodils were so beautiful...
Thousands of daffodils at a park in London (photo from Flower Magazine)
After a tough summer with countless hailstorms, my gardening motivation has withered. But the thought of starting next year with cheerful and colorful spring bulbs got me excited. So I indulged and bought bulbs. Lots and lots of bulbs. Too many bulbs. I got them home and thought to myself, "Oh no. Now I have to plant these things."
Lots and lots of bulbs to plant. Sigh.
I bought a total of 93 bulbs (allium, hyacinth, daffodils, tulips, crocus). I picked out my bulbs by hand, but if you're planting en masse, then purchasing in bulk is easier and likely cheaper. You can also time bulbs based on bloom period (early, mid or late spring) and color. Confession: I picked out a lot of my bulbs because of their name. For example, I had to buy the hyacinth 'Jan Bos'. Jan is my mom's name and we had a dog named Bosley growing up. Jan Bos!

After such a dry summer, the thought of trying to dig in our soils nearly made me go rest on the couch. But I didn't! And I got those bulbs planted. All of them. And here's how I did it:

Spring bulbs are pretty easy to work with. Essentially, you dig a hole, stick the bulb in, roots side down (pointy end up!), and cover with soil, and water in. Easy peasy. But the type of bulb and the depth at which you plant is important. You're aiming to plant the bulb about 3-4 times the height. So bigger bulbs need deeper holes. Small bulbs are just barely below the surface.
A little comparison of planting depths. Crocus are only 3" below the soil surface; daffodils can be up to 8", depending on the size of the bulb you're planting.
You can decide what bulbs you want to plant together...or have large clumps of the same type. In general, small bulbs will look better if planting in large patches. Large bulbs, like the giant alliums, can stand alone. Hyacinth have wonderful fragrance and the impact is better when in groups. Some bulbs will naturalize and form large clumps over the years (daffodils, squill). You can even plant big bulbs together with small bulbs in the same hole--you just fill in the hole with soil for the correct depths for the bulbs you're planting.
Daffodils just poking their heads out before they are planted.
I planted the bulbs in several areas throughout the front yard. I have planted bulbs in the past, so accidentally sliced a few of the older ones. Oops. But what's fun to see are the new roots that the old bulbs are forming. Check out these crocus:
Crocus that were uprooted during the new bulb plantings. I just tucked them back in.
Following planting, be sure to water in your bulbs and cover with mulch. If you have animals that like to dig up plants, place chicken wire over the top of the planting hole. Consider planting bulbs that are deterrents to animals, like frittilary, allium and snowdrops, among others.
Water in your bulbs and cover with mulch.
The great thing about bulbs is that you kind of forget you planted them and next spring it's a fun surprise to see them bloom! Just knowing the bulbs are there gives my tired fall garden a boost. I'll try to remember to take photos in the spring for you.
(The tired fall garden.)
In the front of this bed I planted 30 crocus and small alliums.
Get out and plant some bulbs--our Front Range Colorado soils tend to stay warm until November, so try to plant by mid-October so that the bulbs can form new roots before the soil freezes. They also need several weeks of cold treatment in order to bloom in the spring. Need more information? Check out the CSU publication on fall planted bulbs. Oh, and should you fertilize? Well, I never fertilize anything in my landscape. The bulb you plant this year should have plenty of "oomph" to bloom next year. If you keep bulbs year-to-year, they will benefit from fertilizer following bloom next year.

The best part about planting was finding this praying mantid...she (he?) was perched on top of my rose, enjoying the beautiful fall day.....and waiting for something to eat.
Hello, world!