Monday, November 18, 2019

Drought hits most of Colorado Again, pray for snow!

By Susan Carter
Here we go again.  Many of you remember the drought of 2017-2018, second worst on record.  Some parts of our state where there is no irrigation did not even bother planting crops; some areas were on water restrictions and then came the snow the winter of 2018-2019.  That was a godsend.  If we would have had two years in a row of severe drought, we would have been hurting for water resources.  With the winter snow and the wet spring, sources of irrigation and domestic water filled up beyond what was expected.  For a brief period, the entire state had no, zero, nada drought.  Then the drought started creeping up from the southwest corner again.  Now ONLY the north to northeast corner of Colorado is not in drought.  Note the Water year starts in October.
So what does this mean for your garden and perennial plants including trees?  Drought stress is not something that just goes away because you watered once or because for a brief period, the state was not in drought.  Water is one of the key ingredients in photosynthesis and other plant processes that help the plant create carbohydrates and move water and nutrients throughout the plant.  When plants cannot adequately produce food, they use up their reserves.  Each plant, like people, is different due to the environment and the type of tree as well as its specific genetic makeup.  So some plants will bounce right back, where others will stumble along for a few years before they give up because they have exhausted their resources.  In addition, stressed trees attract insects that can also exhausts the tree’s resources as they cannot fight off the insects or recover from the damage done.
Old Pinon Pine with IPS Beetles- Incorrect water stress
Photo By Tom Ziola
Leaf Scorch- drought can be a cause
Photo by Susan Carter

So how do we deal with drought that seems to come more often?  Well we can properly water, winter water, direct downspouts etc… to keep what we have alive.  Then we can start by replacing plants that have died with more drought resistant plants.  Remember, if you have a tree in a lawn and you remove the lawn and install rock what have you just done?  The root system of that tree is totally under the lawn.  A tree’s root system is at least twice its width or 2-5 times the height.  Ninety percent of the roots are in the top 12-18" of soil.  That area needs water.
Watering photo from CSFS
Trees are like people in that they do NOT like change.  To change a watering zone from frequent watering of turf to watering the tree root zone, you have decrease the frequency slowly.  You have to wean it off the watering to the appropriate 10, 20 or 30 day of watering interval for the type of tree and environment. (Watering Mature Trees)  I could go on with more ways to save water, but I think that is a blog for another day, the point is think about drought affects, where you water and why you water and come up with a long term plan. 

Snow around Plum trees
Photo by Susan Carter

In addition, we can hope for more snow!  If the ground is dry and frozen when the snow arrives, it does not hydrate the parched soil.  If the soil is dry, but not frozen water so there is moisture in the soil (but not saturated) so if it thaws again there is water available to the roots.  Plants need to go into the winter with moisture available to them as they continue to respire and give off moisture even if they have dropped their leaves.  Of course evergreen plants like pine and spruce trees, evaporate due to having leaves all winter.  A dusting of snow is not very helpful either.  It can just evaporate.  Snow at least 6” deep can insulate the ground and provide enough moisture when it melts to help.  Then there are the reservoirs that need to fill so we have irrigation and domestic water.  So let it SNOW!

Susan Carter is the CSU Extension Horticulture and Natural Resource Agent for the Tri River Area.

Monday, November 11, 2019

Ric Rac Orchid Cactus (Epiphyllum anguliger) by Irene Shonle

My fishbone or Ric Rac orchid cactus this year finally is large enough to have had a wonderful blooming period, and I am smitten!  The fall-blooming flowers are large and white with yellow-orange sepals, and are delightfully, waftingly, fragrant at night and early morning. To me, they smell like Easter Lilies mixed with a little citrus blossom - quite lovely.  The sad part is that each flower only lasts a day - two at the most, so you have make sure you are home to enjoy them. Cancel all out of town travel when you see the buds enlarging! I’m not sure you have to stage a viewing party like people do with their Night Blooming Cereus, but on the other hand, it doesn’t seem over the top, either. My cactus had two flushes of blooms this year, a couple of weeks apart. We’ll see if that is an ongoing phenomenon. 
Ric Rac Cactus flower (Epiphyllum anguliger)

Even out of bloom, it is a worthwhile specimen - the long stems have a unique foliage, giving the plant its common names.The flat, deeply lobed stems vaguely resemble a fishbone. It’s also so called ricrac orchid cactus because ric rac ribbon has that same shape.  The stems are long and arch before trailing downward, giving it a wild and slightly octopus-like appearance. It makes a terrific hanging basket plant!

 Epiphyllum anguliger is a cactus species endemic to Mexico, occurring as an epiphyte in evergreen forests in Guerrero, Jalisco, Nayarit and Oaxaca. Epiphytic plants actually grow on trees or other plants, and find soil and nutrients trapped in small pockets where the branches emerge from the tree trunk.

Epiphyllum anguliger is easy to care for and very low maintenance. I have found they are less finicky than my spring-blooming Epiphyllum which I wrote about in a previous blog ( The fragrant flowers open at night may last into the day on cool cloudy days.

The plants prefer partial to dappled shade or bright indirect light, making it easy for most households to find a location for them. They would NOT appreciate a south or west window.

Because they are epiphytes, they prefer a well-drained soil. They prefer to be somewhat root bound, so don’t pot them in a very large pot. They should not be kept overly moist in order to prevent root rot.  Allow the soil to become semi dry between waterings. They would appreciate a little extra water during the growing season (spring to late summer as a general rule) and should be kept slightly dryer when not in active growth (late fall and winter).  Give plants a brief rest at the end of each flowering period by watering only enough during the next two or three weeks to prevent the potting mixture from drying out. It can be fertilized with a weak cactus or orchid feed over the growing season every two weeks or so. Do NOT over-fertilize.

If your friends fall in love with your cactus after your viewing party, not to worry. The plant is easily propagated. Break off a stem and allow it to callous over a few days before planting. Put in a light soil mix and water lightly. Do not disturb until you see new growth. This may take over a month. 

The occasional unruly long stem can safely be cut back to shorten. New stems will usually grow right from the cut area, and this can help to increase the fullness of your plant. It will also give you a supply of branches for propagation.

You’ll need patience and a bit of room to let this plant come into its full glory, but you won’t be sorry you brought it into your house.

Thursday, November 7, 2019

2019 "Best Of" Winners Announced from CSU Annual Flower Trial!

Posted by Jim Klett, Professor, Department of Horticulture and Landscape Architecture, Colorado State University

Each year, the Annual Flower Trial Garden tests and analyzes the performance of more than 1,000 varieties of annual bedding plants in Colorado’s harsh growing conditions.  Dozens of expert evaluators rate the plants for vigor, growth pattern, bloom and other characteristics.  The trial results help home gardeners identify annual bedding plants that are most likely to succeed.  For more detailed descriptions and photographs, visit  The following are some of the winners selected from the 2019 trial: 

Best of Show – Dahlia ‘City Lights™ Purple’ from Selecta 
The dark foliage and flowers of this variety made a dramatic statement in the garden.  The growth habit had excellent uniformity with upright plants that did not flop despite overhead irrigation.  Plants had strong flower power and were favorites of the bees. 

Best Novelty – Begonia T-REX™ Ruby Slippers from Terranova
The huge red leaves had silvery edges that would make a great contrast for color and texture with other plants in the garden.  Plant is grown mainly for the foliage.  It made a very eye-catching plant for areas with dry shade and can be used in either the ground or in containers.

Best New Variety – Petunia ‘Headliner™ Dark Saturn from Selecta
The unique flower color was very impressive with a bold soft creamy yellow and a dark star shaped eye.  Plants had strong vigor and developed into a uniform blanket of blooms in the container.  Plants and flowers held up well in the heat. 

Begonia (shade) – ‘BK Collection Vermillion Red’ from Beekenkamp
The overall appearance was striking all through the season with a very intense, rich shade of red and abundant blooms.  In addition to the prolific flowering, blooms were double which greatly added to the overall show.  Plants had dark green foliage and were very uniform.

Begonia (sun) – ‘Tophat™ Pink’ from Syngenta Flowers
Plants had great vigor but maintained a very uniform growth habit.  Flowers were unusually large and very abundant which made them immensely popular with the bees.  Plants looked great in either the ground or container and only got better looking even into the fall.

Bidens – ‘Campfire™ Flame’ from Proven Winners
Flowers had beautiful shades of orange/red/yellow and fade to a nice rustic color.  Blooms were prolific and kept a solid canopy of color all through the summer and into September.  Growth habit was very uniform and the overall effect was quite striking in a container.

Digitalis ‘Pink Panther’ from American Takii       
This plant flowers the first year on compact plants with small foliage.  The heavy branching produced multiple spikes at one time and did not require pinching.  The sterile blooms are long lasting and attracts pollinators.   Pink flowers are abundant and very attractive.

Geranium ‘Clarion® Peach’ from Benary+
This regal type of geranium had large blooms with truly mesmerizing shades of peach, pink and white.  The uniform, mounding plants were covered by blooms all season long and were a definite show stopper.  Other entries in the same Clarion® series were also impressive with excellent vigor and flowering.

Impatiens – ‘Beacon™ White’ from PanAmerican Seed
Snowy white flowers covered the plant canopy providing a bright splash of color for shady areas.  The vigorous plants maintained a controlled growth for excellent uniformity.  The added bonus for the entire ‘Beacon™’ series is that they have strong resistance to Impatiens downy mildew which has devastated many Imapatiens walleriana in the past few years.

Lantana – ‘HAVANA Sunrise’ from Dummen Orange
This heat loving plant had good branching, large umbels of flowers over dark green foliage. The compact growth habit with prolific very attractive multi-colored flowers with shades of pink, cream and yellow makes it outstanding. It has a very uniform growth habit and looked great in a container.

Petunia (container) – ‘Crazytunia® Tiki Torch’ from Westhoff
Flower color was exceptional with a bold and colorful combination of red, yellow and orange.  Combined with strong plant vigor and abundant flowering, this entry was clearly a standout.

Vinca – ‘Soiree Kawaii Coral’ from Suntory
Tiny coral colored flowers were bright and prolific making an impressive display of color in either ground or containers.  Additional features were the small white eye on the bloom and glossy green foliage.  Plants stayed compact all summer long with no leggy branches.

Zinnia – ‘Zesty™ Scarlet’ from Ball Ingenuity
Vibrant scarlet flowers had great flower power with the abundant flowering and uniform growth habit.  Plants had excellent vigor and were disease free all-season long.

Monday, November 4, 2019

Where Do Bees Go in the Winter?

Posted by: Lisa Mason, Arapahoe County Extension

I have been asked a few times this season what happens to the bees in the winter. Bees and other insects have special adaptations, so their species survives from year to year. Here is a look at bee adaptations and life cycles in the winter time.

Honey Bees
Worker bees foraged all summer and into fall bringing in food reserves to last them the winter. When temperatures start to drop, honey bees huddle together to make a cluster and shiver their wings. Shivering provides warmth for the hive. Their main goal is to keep the queen warm so the colony can survive. The core temperature in the hive can be as high as approximately 91 degrees Fahrenheit. A healthy hive with adequate food storage is more likely to survive, which reinforces the importance of best beekeeping practices by the beekeeper all year. Read how to prep a hive for winter here.
A honey bee, Apis mellifera. Photo: Lisa Mason
Solitary Bees
Solitary bees live a one-year life cycle. During the life cycle, a female bee builds a nest underground or in a cavity. She will collect pollen and nectar to bring back to the nest. All the collected pollen and nectar is made into a ball called “bee bread” which will be all the food needed for one growing bee. The female lays an egg on the bee bread and seals up the nest. After the egg hatches, the larva will go through full metamorphosis from a larva, to a pupa, and on to an adult before emerging from the nest the following season. The lives ended for the female and male solitary bees we saw flying around this summer, but their brood is warm for the winter underground or in a cavity, and will emerge next summer.
An overview of the solitary bee life cycle. Graphic: Lisa Mason

A native bee emerging from her underground nest. Photo: MaLisa Spring
Bumble Bees
Bumble bees live underground or in large cavities and have a one-year life cycle, like a solitary bee. During the summer, new queens and male bees hatched. They left their colonies to mate. As temperatures dropped, the male bees and worker bees from the current season’s colony died. The new, mated queens found a place to rest and hibernate over the winter, usually underground. When spring arrives, she will emerge, begin to forage, build a new nest, and lay eggs. The eggs will mostly be female worker bees at the beginning of the season. The queen will continue to lay eggs throughout the season. In late summer, new queens and male bumble bees will hatch and leave the colony and the cycle repeats itself. Queen bumble bees are capable of living alone, unlike honey bee queens.
A bumble bee, Bombus sp. Photo: Lisa Mason
For more information on bee life cycles, you can read the Native Bee Watch Citizen Science Field Guide.

For more information on what happens to other insects in the winter, you can refer to this CO-Horts Blog post written by Jessica Wong.

Monday, October 28, 2019

A Halloween Love Story

By Carol O'Meara, CSU Extension Boulder County

Send the children from the room.  Normally this is a family column but in celebration of the end of October, I wanted to share a Halloween love story.  You see, some time ago, another CSU Agent asked if it’s true that spiders scream while mating.  Her friend had read this in the paper and was fact-checking it. 

This set me to wondering: why would they?  From the female’s perspective, the wooing and winning of love often involves having to endure the male dancing about, rushing in to tap her on the head to see if she’s interested, and dashing away in case she’s not.  This goes on, back and forth, until the male, convinced of success at winning her heart, gently enfolds her in his arms.  All eight of them.  Who wouldn’t scream at being held in arms covered in spines and tipped with claws?

How delighted she must be when he runs his fangs in a loving caress along the back of her head.  Oh, yes, the male doesn’t like to approach the front – that’s where her fangs are, after all, and one mustn’t take chances.  His embrace is from the back, and since the female is typically much, much larger than the male, he has to hold on somehow.  His fangs come in handy to use in gripping her in the embrace.  How romantic.

If this weren’t enough, ladies, consider that the male spider has not one, but two pedipalps - the male spider genitalia - with which to woo her.  

Female spiders aren’t the only ones who have good reason to scream.  There’s a lot of risk involved for the male and the whole episode is one long stressful event.  After his final molt, a male spider will leave his web in search of a female.  He may no longer hunt or be interested in food.  Instead, he is so consumed with finding the female that he may wander far and wide to find her. 

This often leads him into danger such as other spiders, predatory birds, or into human houses.  Males wandering in the fall are a large proportion of spiders found in our homes, often meeting a tragic end under some human’s shoe.  The female doesn’t engage in such nonsense; she has better sense than to give up her food and housing just to search for a guy. 

Once the female is found the risk increases.  They are almost always larger, faster, stronger, and, quite often, hungry.  It’s a thin line between being a suitor and being a supper, and males must take steps to ensure that the female is well fed before any love happens.  Some males will use the ‘tap-and-dash’ method to test her willingness, others take no chances and bring living food as a nuptial gift.  “Here, have a fly - enjoy it”, is a good plan when wooing a female of any species.

Once she accepts the male, it’s still risky.  Yes, the male has two pedipalps and that may seem impressive and worth boasting over.  But there is a rather gruesome reason for this:  in many species, after the nuptials take place, the male must seal off the female to make sure no other male can impregnate her.  He does this by snapping off the pedipalp to leave as a plug.  When a spider decides to ‘break it off’ with his girl he really means it. 

To answer the question “do spiders scream while mating?” one has to respond: “who wouldn’t?”  The reality is that spiders don’t have vocal chords or bellows-like lungs with which to scream.  Their sounds come from rubbing legs, drumming the ground and other external means.  Thus, the answer is no, but that doesn’t mean they wouldn’t if they could.

Friday, October 25, 2019

Which Trees to Transplant in the Fall in Colorado

By: Emily Jack-Scott (Garfield County Colorado Master Gardener)

As a rule of thumb the best times to transplant most trees and woody shrubs is in early spring (as soon as the soil can be worked), or in fall (after leaves drop) – the key factor being that the tree or shrub is in dormancy. In some parts of the country, fall planting is actually preferable since most trees are channeling energy into root growth in autumn, as opposed into shoot and leaf growth in spring. However in Colorado, fall can be less ideal since the ground can be very dry in winter and roots of transplanted trees can suffer additional damage. If you do choose to transplant a tree or shrub this fall, there are several considerations that can improve your odds for success.

Firstly, aim to complete the transplant by the end of October. Transplanting any later in fall or winter will leave little opportunity to help water in the new planting before the ground freezes. New transplants are particularly susceptible to winter drought injury due to the dry winter soils in Colorado. This can be curtailed in part by winter watering, which is critical for newly transplanted trees and preferable for all established trees and shrubs in Colorado (refer to Fact Sheet 7.211 Fall and Winter Watering for more information). Winter drought can also be helped by properly mulching a newly transplanted tree (refer to Fact Sheet 7.214 Mulches for Home Grounds).

The species of the tree also factors into transplanting success. This is in part due to the difference in root structure between different species – with some species having shallower, more fibrous root systems that are better adapted to transplanting, especially in fall. Some types of trees really should only be planted in spring including oaks, fruit trees, poplars, willows, redbuds, and birches. Other species can be more successfully transplanted in the fall such as maples, alders, lindens, catalpas, elms, ashes, and honeylocusts. Conifers such as pine and spruce benefit from being transplanted when soils are warmer.

Whether you choose to transplant a tree or woody shrub this Fall or wait until Spring, ultimately the success of your planting depends on following proper tree-planting steps (refer to GardenNotes #633 The Science of Planting Trees). Happy planting!

Additional Resources: