Friday, April 30, 2021


By Cherie Luke

Rheum rhabarbarum, commonly know as rhubarb, originated in China and the Himalayas. It is a true harbinger of spring! Botanically it is a vegetable because we eat its stems and not its fruit, but it is used like a fruit in pies, tarts, crisps, and even in wine making. 

Rhubarb crowns are best planted in early spring or late fall in well drained soil with plenty of organic matter. In a sunny location in your yard, dig a hole so the crown buds are 2-3 inches below the soil surface. Rhubarb plants need plenty of space to grow, so plant them 4-6 feet apart. 

Rhubarb emerging in spring

Mulch plants with compost to provide nutrients and to retain moisture during the summer. Keep your rhubarb patch free of weeds so it will not likely be disturbed by diseases or insects. The first year you should let the rhubarb grow without harvesting any of the stalks so your plants can become established. The second year, if the plants show vigorous growth, you can harvest a light crop. By the third year you can harvest most of the stalks. 

The leaves of rhubarb contain the toxin oxalic acid and should be kept out of reach of children and grazing animals. The leaves can be composted without any danger. Rhubarb can live for 15 years or more with little attention but will benefit from a top dressing of compost or rotted manure in fall, and also by occasionally dividing the roots. If seeds stalks appear they should be removed so the plants can focus their energy elsewhere. 

Rhubarb requires two months of freezing temperatures to break their rest period. Rhubarb like a long cool spring, which makes it an ideal plant for mountain gardens. It is hardy in zones 3-8. 

CSU has a short video on how to harvest your rhubarb. #rhubarb

Friday, April 16, 2021

Watch Your Woody Plants for Damage Caused by Environmental Stress

By Kristina Hughes, Clear Creek County Master Gardener

In spring of 2020 I noticed my hawthorn, lilacs and roses were struggling. They leafed out much later than usual and were growing very slowly. My neighbors were having the similar issues with their woody plants. There was much more winter dieback than usual, even on native plants.


I consulted the Plant Diagnostic Clinic and learned that the damage was a result of the sudden, extreme freeze that had occurred in April 2020, a few months prior. There had been a warm spell and the plants had started to leaf out, then the temperature plunged more than 40F. The first round of growth and buds had frozen. The plants then tried to push out leaves again later in the spring, but by then it was very dry. Plants need water to fill out their expanding leaves and there wasn’t enough water in the soil at that time for the plants to fully expand the second set of leaves. I realized that if the plants were stuck with stunted leaves for an entire growing season they would only generate a fraction of the energy that they would normally make in a season. The entire plant would be weakened the next year.


So I followed the advice of the Plant Diagnostic Clinic and watered my woody plants very well. It took a concerted effort to water by hand until the entire root zone down 12”-18” was moist. But I did it quickly and I watched my plants expand their leaves to full size. I knew they would have a fighting chance of recovering from the freeze damage. 


Late frost damage. Photo by Dana Ellison.

I bring this up now because stress to woody plants can take a long time to show up. The damage done during the extreme freeze of Easter 2020 can continue to appear during this growing season. This year we’ve had a dry and warm winter which has added more stress to the plants, so I’m going to continue to watch my woody plants closely this year and make sure they have enough water if they look like they’re struggling.


For more information on freeze damage:


Jeffco Clinic’s Top 10 Plant Problems of 2020


Environmental Disorders of Woody Plants (sections on drought and freeze damage)


Jefferson County Plant Diagnostic Clinic diagnoses samples for a small fee

Friday, April 2, 2021

High Altitude Natives

By Sandy Hollinsworth, Gilpin County Master Gardener

Increasingly, mountain gardeners and homeowners living above 8,000 feet are interested in landscaping with native plants to increase success and promote sustainable, natural habitats. Native plants are inviting to pollinators, birds, and mammals by providing food, shelter, and nesting material. There are many benefits to using Colorado native plants including biodiversity, beauty, adaptability, plus many are fire-wise plants. They are naturally adapted to Colorado’s climates, soils, and environmental conditions. By choosing native plants, gardeners can work with nature, rather than trying to grow plants that are not suited to our local high-altitude conditions. Native plants are also more resistant to pests and disease when grown in areas where they are found in nature.

The mountain region is characterized by short growing seasons, cool nights, strong sunlight, and high winds. The soils tend to be decomposed granite, low in organic matter, and are usually very well-drained. Many native plants prefer particular soil textures, whether sand or clay or loamy soils. Almost all high mountain natives do not last as long in enriched garden soils; they grow faster and may look fabulous for a few years then die sooner. Because native plants are adapted to native soils they will thrive without fertilizer or soil amendments. A small amount of compost may help work the rocky soil, but gardeners will benefit by using compost sparingly. Species like columbines and Jacobs ladder that grow in moist forests, may benefit from more compost but otherwise, plant natives without fertilizer and other amendments.

Another consideration is microclimates, sections that are hotter and drier, or cooler and wetter than the rest of the property. Every garden and property have microclimates, depending on shade, sun, slope, water, and wind protection. Grouping plants with similar sun, water, soil and protection requirements will add to success and help with supplemental watering as needed. Colorado mountain natives generally require less water unless they naturally grow in riparian areas like Bluebells, Parry’s Primrose, Scouring-rush Horsetail or Blue-Eyed Grass.

Maintenance in your garden may be easier with natives. It is recommended not to rake away all dead leaves and twigs as it helps protect the soil and offers protection to overwintering pollinators. In fall it is best not to cut back plants but instead to leave seed-heads and dead stalks for food, perches and winter homes for native bees, beneficial insects, and wintering songbirds. Wait to cut back dead plant stalks in early spring at the first sign of green-up.

Mulch is critical for starting native plants from seed, and it can be a huge help in establishing nursery-grown plants too. Gravel mulch is best for retaining soil moisture without causing crown or root rot. Next best is locally-sourced shredded bark mulch although it can blow away.

Non-native plants that are adapted to Colorado’s climate, including CSU Plant Select species, may be more readily available. In years with less than normal rainfall and snow these non-native plants may need supplemental water, again pointing out the adaptive advantage of native species. Gardening with native plants also prevents the introduction and spread of noxious weeds. Many noxious weeds were intentionally introduced as garden plants and can crowd out or change the garden’s native characteristics.

In Gilpin County, the following list of native plants are found at 8,500 – 9,500’ on nature hikes and in established natural habitats. Most are available at local native oriented nurseries or through CSU Extension native plant sales. Inquire about sun and water recommendations to make sure to plant the right plant in the right place. Seedlings will take a few years to fully establish. Some reseed freely while others stay put and grow to their mature spread and height over time. Wind, furry critters, birds, and domestic animals may help spread seeds.

Pussytoes Antennaria spp

Kinnikinnick Arctostaphylos uva-ursi

Sulfur Buckwheat Eriogonum umbellatum

Common Yarrow Achillea millefolium (lantana)

Nodding Onion Allium cernuum

Pearly Everlasting  Anaphalis margaritacea

Fringed Sage   Artemisia frigida

Fringed Sage Artemisia frigida

Rocky Mountain Columbine Aquilegia caerulea

Blue Grama grass Bouteloua gracilis

Harebell Campanula rotundifolia

Indian Paintbrush Castilleja spp.

Rocky Mountain Bee Plant Cleome (Peritoma) serrulata

Showy Fleabane Erigeron speciosus

Wallflower  Erysimum capitatum

Blanketflower  Gaillardia aristata

Richardson’s Geranium Geranium richardsonii

Sticky Geranium Geranium viscosissimum

Prairie Smoke Geum triflorum

Sneezeweed Helenium  Hymonoxys hoopesii

Showy Goldeneye Heliomeris (Viguera)

Scarlet Gilia Ipomopsis aggregata

Rocky Mountain Iris Iris missouriensis

Blue Flax Linum lewisii

Silvery Lupine Lupinus argenteus

Bee Balm/Horsemint  Monarda fistulosa

Showy Locoweed Oxytropis lambertii

Rocky Mountain Penstemon Penstemon strictus

Blue Mist Penstemon Penstemon virens

Silky Phacelia  Phacelia sericea

Jacob’s Ladder Polemonium viscosissimum

Pasque Flower Pulsatilla (Anemone)

Black-eyed Susan Rudbeckia hirta

Golden Banner   Thermopsis divaricarpa

Current berries

Wax Currant  Ribes cereum                    

Woods’ Rose  Rosa woodsii

Serviceberry  Amelanchier alnifolia

Chokecherry Prunus virginiana

For more information about native shrubs

Almost this same list, plant photos, and some garden design ideas are in this CSU Extension booklet:

Friday, March 19, 2021

Just a Few of My Favorite Useful Plants

By Yvette Henson, San Miguel Basin, CSU Extension

My definition for herbs is ‘useful’ plants.  The Merriam Webster definition of an herb is “any plant with leaves, seeds, or flowers used for flavoring, food, medicine or perfume.” The past two gardening seasons, I have returned to herb gardening like I did when I was first learning to garden, and I have been using my herbs in many ways!  I would like to share with you my favorite herbs and how I use them. Since I garden at 8,400 feet, all these herbs should grow well for anyone who gardens at a high elevation site, with cooler temperatures.

Calendula flowers and seeds

I will start with Calendula officinalis. Most people call it by its Genus name, Calendula, but another common name is pot marigold, alluding the fact that it is edible.  It can be used fresh in a salad or cooked with spinach or added to soup.  It can also be dried and ground and used to color rice, etc. 

Calendula is useful in salves and lotions and is scientifically proven to be good for skin. The variety that is reported to contain high amounts of the compounds that are good for the skin, is ‘Resina’ but any Calendula variety will work. I use the salve for any skin irritation—it is my favorite salve because it is so soothing.  I also made a diaper cream for my granddaughter that works well.  Many recipes can be found on the internet.

You can find Calendula in shades of yellow, orange and peach, the most common being orange.  It is a cool-season annual that grows in average soil.  If happy, it will bloom continuously until a killing frost, and will reseed itself.  The seeds can be collected and re-planted. If stored properly (consistently cool, dry, and dark) the seeds remain viable for about nine years.

German Chamomile, Matricaria chamomilla

For the past two years, I have grown German Chamomile, Matricaria chamomilla, from seed.  When danger of frost is past, I transplant the young, hardened-off seedlings into pots or raised beds in my garden.  I love it for its abundant bloom and delicious-smelling flowers.  It is the yellow disk flowers that contain the fragrance and oils.

Use in tea and infuse in oil for salves. Besides making a calming tea for us to drink, a strong, cooled chamomile tea can be applied to seedling trays at the first sign of damping-off disease, and it really works!  My daughter has eczema.  She uses the salve I made her when she starts getting an outbreak and it clears it up!  It is also a calming salve for babies.

Grow chamomile in well-drained, lean soil. Plant hardened-off seedlings into the garden after chance of frost. Continuously remove blooms as they open to promote continuous bloom.  I dry the cut blooms in paper bags or spread out on newspapers in a dark area. 

Dandelion blooms--Taraxacum officinalis

We built our house on ‘virgin’ land in a Ponderosa/Pinon/Juniper forest. I was so dismayed when the dandelions started coming up— I did not want anything non-native growing without my permission.  Apparently, we brought them here, because they were not there before. Although I tried to remove them, each year they multiplied in number, until I finally gave up. 

Now, I pick the young greens in early spring and sauté them in oil with a dash of lemon at the end.  What a yummy, although bitter, green for an early spring ‘tonic’!  I also make salve by infusing the dried blooms in oil.  I like the dandelion salve for lip balm and to massage sore, dry feet and ankles.  My daughters agree that it is helpful—we do not know if it is the massage or the dandelion oil or both, but it eases the pain. 

I am not recommending that you plant them on purpose—I am sure you can find some dandelions, somewhere, preferably in a place where no weed killer was applied.  Last year, my favorite spring mornings were spent in the sun, watching the bumblebees collect pollen from the dandelion flowers while I picked a bag full of blossoms.  So, why not make a few dandelion chains and blow some seeds into the wind--“If you can’t beat ‘em join ‘em!” -- I think I may make dandelion jelly this spring.  

Friday, March 5, 2021

What is the purpose of wasps?

 By Lisa Mason, Arapahoe County Extension

What is the purpose of wasps?

I am asked this question quite often. Why do we have wasps? What is their purpose? Do we need them?

We have a couple of wasp species that can be a nuisance to people. They tend to give wasps a bad reputation. In reality, wasps are a fascinating, diverse group of insects that play a critical role in our ecosystem!

A beneficial sand wasp (Bembix sp.) hunts caterpillars and flies. They can often be seen visiting flowers for nectar in the summer. Photo: Lisa Mason 

Here are some important facts to know:

    • Two species of wasps Colorado are considered a nuisance: The Western yellow jacket (Vespula pensylvanica) and the European paper wasps (Polistes dominula).
    • Besides those two species, wasps are a very diverse group of insects with thousands and thousands of species documented worldwide. How diverse? Current science says that beetles (Coleoptera) are the largest group of organisms on the planet representing about a quarter of all described species. However, some research suggests that parasitoid wasps are actually the largest group of organisms but we haven’t been able to document all the species. Here is a fun NPR article on subject.
    • Many wasps can’t actually sting including parasitoid wasps and other solitary wasps.
    • Most wasp species are solitary insects. Only wasps in the Vespidae family are social and live in colonies. Often, the social wasps are brightly colored to warn predators that they are dangerous. They will defend their nest and sting if needed.
    • Many other insects mimic the bright colors of social wasps to protect them from predators. This phenomenon is known as Batesian mimicry. Common mimics include flies in the Syrphidae family, also known as flower flies or hover flies. You can observe these harmless insects in flowers in the summer time.
    • Wasps provide valuable ecosystems services to humans because they provide pest control in your landscape. Some wasps are predators and others are parasitoids, meaning the wasps will lay eggs in another host insect and consume the host. Our world would be full of pest insects without wasps!
    • You can thank paper wasps for our current paper production industry! In the 1700’s, paper was made from cotton and linen until there was a shortage of those materials. A French naturalist named Antoine Ferchault de Réaumer had observed how paper wasps use wood fibers to make their paper nests, and thought people could do the same thing to create paper. Paper products today are still made out of cellulose fibers from wood (Paulson and Eaton, 2018).
    European paper wasp (Polistes dominula). Photo: Lisa Mason

    A syrphid fly (Spilomia sp.) that mimics stinging wasps but can't sting. Photo: Lisa Mason 

    What about the “murder hornets”?

    The Asian giant hornet (Vespa mandarinia), the world’s largest hornet, has received a lot of press recently because a small number of individuals were found in Washington state. While the insect may look intimidating, much of the news media is sensationalized.

    I encourage you to read a media interview with Dr. Cranshaw, CSU entomologist. He talks about how calling them “murder hornets” is unnecessary. Many wasps are predators and hunt other insects. The Asian giant hornet is no different. 

    Much of the media has focused on how Asian giant hornets preys on honey bees. While they can prey on honey bees if near a hive, Asian giant hornets are generalist predators. They will feed on a variety of insects and will be opportunistic in hunting. They will not specifically target honey bees unless there is a hive nearby. Beekeepers around the country have more important challenges concerning honey bees including the varroa mite.

    Will the Asian Giant Hornet come to Colorado?

    Short answer: No. We don’t have to worry about the Asian Giant Hornet coming to Colorado for the following reasons:

    ·       Asian giant hornets thrive in different climate than Colorado. They need low-elevation areas and higher moisture levels.

    ·       There are many geographic barriers preventing the Asian giant hornet from spreading including the Rocky Mountains.

    ·       They are unlikely to hitchhike like some other invasive species. 

    ·       Efforts to eradicate the hornet is Washington are occurring now.

    What if I find an Asian Giant Hornet in my backyard?

    Colorado has some wasp species that large and may appear to look similar to the Asian giant hornet. These wasps are harmless and common in Colorado landscapes. The two wasps that may look like the hornet include cicada killers and horntails. Both of these wasps cannot sting you. 

    Cicada killers target cicadas when hunting and provide the prey to their young.

    Horntails appear to have a large “stinger.” This “stinger” can’t sting you at all! It is called an ovipositor, which is adapted to drill into the bark of trees. Female horntails lay their eggs underneath the bark of trees. They don’t harm trees and tend to lay eggs in trees that are already stressed out.

    Solitary wasps such as these found in your landscape are not aggressive and should be left alone. 

    If you are looking for the identification of a wasp found in your landscape, contact your local Extension office for assistance.

    Here is a visual of the Asian giant hornet compared to common, harmless wasps including cicada killers and pigeon tremex horntails. Photo: Texas A&M Extension

Stay tuned for more info on wasps!

Look for future blog posts about wasps! I will discuss the differences between social and solitary wasps, and well as some common and beneficial wasps you might see in your backyard.

Wasps can be scary to people for a variety of reasons, but I hope to article can help instill some appreciation for what all wasps contribute to our ecosystems.

Friday, February 19, 2021

Indoor Plant Fun

By Ed Powers, Jefferson County Master Gardener

It has been an interesting 14 months. My wife and I have been quarantined this whole time. Like a lot of people we have been catching up on things we fell behind on. We spent our whole summer working on our outdoor gardens. Our flowering plant pots were highly successful, but our vegetable garden was eaten up by the wildlife in our area. We had the garden protected with double netting but the voles and mice got through it and had a feast. So this spring we are going to dig up and turn over our raised garden soil, and find a new protection for them.   

But our indoor plant gardens have been fun. We rely on background info from CSU factsheets and Garden Notes for information on how to take care of them. I can not say enough positive things about these resources. The types of plants we have can be very challenging. We have orchids, African violets, many types of  succulents and cacti. A desert rose, miniature ficus trees, small Japanese Red Maples, indoor geraniums, pothos, ivy, mother-in-law tongue, a small nursery that I start plants in, a small Japanese Black Pine that I am trying to bonsai, several Christmas cactus and a hanging bag full of outdoor plants that I brought in for the winter to see if they would make it.

Plants on steel shelves with only natural light.

Now you may ask how do we house and care for these plants? They are housed in our garage, turned into a sun room and workspace area. It has no heat except for heat coming through basement open areas such as doors or windows.  Our sunny areas face the southwest and some northerly exposure.  We have our stronger plants on steel shelving with some artificial light. We have also put bubble wrap on the windows for insulation while letting the sun light in. The temperature averages between 62 F and 67 F during the winter although when we get below 10 F outside that temperature can drop to 58 F.  

Bubble wrap on windows for insulation and light.

These steel-shelfed plants include all our trees, succulents, desert rose, Christmas cactus, mother-in-law tongue and Japanese Red Maples. They all seem to do well even when it is colder.  Our more sensitive plants are on a plant stand draped with a plastic curtain in back and bubble wrap in front, which can be lifted and thrown over the back of the stand on warm days. The bubble wrap is two sheets 18 inches wide with openings in middle and ends, allowing circulation in the stand. 

Orchids on first shelf of plant stand.

The stand has three shelves. When planting seed in early spring, I put them on the bottom shelf in trays. All shelves are lit with LED lighting. The top shelf holds the orchids, African violets, our small plant nursery and newly rooted trees, and is heated with a heat mat that is controlled by a thermostat.  The second shelf does not have a heat mat. It holds geraniums, pothos and ivy. The stand usually is 65 F to 70 F.  But on colder mornings it may drop to 61 F.

Plant nursery, African violets and newly started ficus trees on first shelf of plant stand. 

All in all it has been a fun time with our plants during this Pandemic and we hope to continue with our success when the Pandemic has passed.

Friday, February 5, 2021

8 Ways Cover Crops Can Improve Your Garden

By Patti O’Neal, Jefferson County Extension Horticulture and Urban Food Systems

Cover cropping, a strategy also known as green manure, has been practiced by gardeners and farmers the world over for over 10,000 years. This organic restoration practice can boost your garden noticeably the very first year you incorporate it into your own best management practices and the improvements increase even more each year as their effects accumulate. These crops are easy to use, do not need much care beyond watering and a mowing/cutting or two and provide tremendous advantages to the garden and gardener.

Cover crops are plants that are considered soil builders. Here are 8 sometimes overlooked ways that cover crops build the soil productivity in your garden:

·       Provides Beneficial insect habitat – pollinators, honeybees, beneficial predator insects will all enjoy the nectar as well as the shelter these crops can provide at every season you use them.

·       Smothers weeds and suppresses their seed from germinating as well.  They provide a dense mat to keep the light from reaching the seeds.

·       Better, more complete soil tillage than any mechanical method.  These crops improve soil structure, allowing more air and water penetration. They can break up soil compaction, loosen tight, hard, or heavy soils and create good tilth.

·       Provides shade for the soil for cooler root temperatures, less moisture losses during hot weather.

·       Acts as a living mulch when established between vegetable rows.

·       Increases organic matter in the soil while feeding the microbes, beneficial bacteria, fungi, and earthworms living in the soil.

·       Conserves soil moisture both at the surface of the soil and in the critical root zone. The extensive root systems conserve soil by reducing erosion from rain by slowing water flow across and through the soil. The living foliage can also buffer wind effects.

·       Fixes nitrogen from the air while recycling nutrients, preventing their run-off and leaching from the root zone, simultaneously bringing up deeper nutrients to plant roots that are usually unavailable.

Use seasonally appropriate cover crops.  Legumes, vetches, rye, and buckwheat are all excellent cover crop plants.  Like all plants, each cover crop germinates and flourishes best in certain seasons. Most reputable seed companies will sell individual crop packets or recommended mixes appropriate for specific season plantings.  Some cover crop seeds are available locally, but seed catalogues have the widest range and generally provide good advice and instruction on using them.

If you are letting a bed or area of your garden go fallow for a season, this thousands year old practice of planting a cover crop can help to replenish the biological community of your soil below while providing nectar as well as shelter for pollinators and beneficials above. Here are a couple of tips to help you be the most successful with a green manure crop.

Allow your crop to flower but watch carefully and do not let it go to seed or you will be battling weeds of a different sort in the months to come.

Flowering red clover

If you plant early enough in the season you can get one or maybe even two mowing’s in (If you garden in raised beds, a weed whacker works great for this) forcing the root material into overdrive to produce another above ground crop.  This action forces the root system further into the soil to depositing additional nutrients while continuing to improve tilth, bringing formerly unavailable nutrients up to the plant root zone.

After your final mowing, fork the remainder of the material under so the microbes and arthropods you have encouraged can break it all down completely to become plant available nutrients.  Be sure and do this at least a month to six weeks before your intended planting date for this bed.  Otherwise, the increased microbial activity will compete with the root establishment of new plants or can even disrupt germination of seeds. You do not want to spoil all the good work you have done.

Ferris helping turn the cover crop

Friday, January 22, 2021

Water Colors in the Garden

By Ginger Baer, Gilpin County Master Gardener

This is the time of the year that we get flooded with our seed catalogs. Oh, to dream of warm, sunny, gardening weather.  Those catalogs do help brighten a grey wintery day. However, when you get through the catalog and make your order, what else can you do?

One of my first paintings

My grandmother and mother were terrific gardeners.  They also were really good at using their water colors to capture the plants that they loved so much. I have many of my mother’s paintings in my home.  I especially love the floral ones because they are reminders of our gardens and sunny, warm weather.

Two paintings by my mother, Caroline English Stancliff

I have gardened as long as I can remember, but only took up painting six years ago when I retired. To get started I took classes at a community art center.  I then bought some lesson books from my teacher to keep me going. I find this to be a great winter-time activity. I am one of those people that needs sunshine and color in the winter.  Painting really helps. I highly recommend it!

Two more of mine. See the sunshine?

So how do I manage to paint a picture of a flower or vegetable when the ground is all covered in white?  Let’s go back to those seed catalogs. Shepherd’s Seeds has great photos.  Botanical Interests has real artsy graphics. If you want to get inspired, pull out one of your catalogs and start thinking of what you love and what would be fun to paint. My mother used to get out the White Flower Farm catalog.  Some of the things that I found in her bag were clippings of flowers right out of a catalog. As a matter of fact, I inherited all of her art supplies.

Some of the supplies from my mother

Of course, there are other mediums you can use besides watercolors. I just happened to have water colors given to me.  Sometimes they are hard, but I love the softness of them. There are oils, acrylics, pastels, colored pencils, and much more.

I didn’t think I could draw, let alone paint. Those lesson books helped. So did practice, practice, practice. Don’t be shy, give it a try! And then have many happy years of painting things from your garden.

Another of mine. How Colorado is that!

Additional Resources:


This is my art instructor


Supplies can be purchased easily on-line.  I have used and


Beginner watercolor techniques -

Friday, January 8, 2021

What is a Pollinator Syndrome?

By Lisa Mason, Arapahoe County Extension

In general, research has shown that plants have specific flower traits that attract pollinators, and the plants provide the pollinator with nectar and pollen rewards. These attractive traits can include flower color, odor, shape, and availability of pollen and nectar. Some plants even have nectar guides which are markings showing where the pollinator should go to collect the reward. Different traits will attract different pollinators. Why would a plant evolve with traits to attract pollinators? Because visiting pollinators will facilitate plant reproduction. This relationship benefits both the plants and the pollinators.

For example, bird pollination is called “ornithophily.”  In Colorado, hummingbirds are primary bird pollinators. We know that hummingbirds generally prefer to visit flowers that are red, orange, or white. The flowers tend to be funnel-shaped, hang loosely on the plant, and have plenty of nectar deep in the flowers. For other birds around the world such as sunbirds, honeycreepers, and honeyeaters, the plants tend to have strong perch support for the bird to land.

Flowers that attract birds typically don’t have an odor, because birds don’t need the scent to find the flowers. You might also notice that the flower petals tend to curve outward to make it easier for a hummingbird in flight to drink nectar.

A female broad-tailed hummingbird (Selasphorus platycercus). Note the pollen on her head. Photo: Nancy Klasky

The USDA Forest Service compiled a chart of pollinator syndromes for the major groups of pollinators.

A wide variety of research is available demonstrating different pollinator syndromes. I want to share two research studies with you.

Darwin’s Prediction of the Long-Spurred Orchid

In the 1860’s, Darwin studied orchids including the long-spurred orchid, Angraecum sesquipedal. He predicted the flowers were pollinated by a long-tongued moth because the flowers have a long spur approximately 12-inches long! The nectar sources are located deep in those long spurs. When Darwin received a specimen of this orchid, his wrote, “… good heavens what insect can suck it” (Darwin, 1862b).

At the time, no pollinators had been observed pollinating these orchid flowers. Scientists predicated pollinator could possibly be the species, Xanthopan morganii, and subspecies, Xanthopan morganii praedicta, commonly called the Morgan’s sphinx moth because they have a proboscis length (tongue-like tube) that averages over 8 inches long. More than 130 years later after Darwin’s prediction, documentation of this moth pollinating the orchid was finally published beginning in 1993 (Arditti et al., 2012). To learn more, I recommend reading this journal article.

Pollinator Syndromes in Columbines

Another research example that we see in Colorado shows that columbines (Aquilegia spp.) have adapted and evolved to attract different pollinators depending on their spur length. This is considered a “pollinator shift” when the plant adapts to the traits of a pollinator (Whittall and Hodges, 2007). 

Besides the spur length, note the other traits the columbines show to attract their designated pollinator. Image credit: Whittall and Hodges, 2007

Your Garden and Pollinator Syndromes

With anything, there are always exceptions to the rules. If you are looking to plant flowers to attract pollinators, you can use pollinator syndromes as a general guideline, but we recommend doing additional research and reading about pollinator-friendly plants that grow well in your area. For instance, to support pollinators, avoid double flowers. Many double-flowered horticultural varieties typically do not have pollen and nectar available for flower visitors.

Here are some resources for pollinator-friendly plant lists:

·         Creating Pollinator Habitat:

·         Attracting Native Bees to Your Yard:

·         Attracting Butterflies to the Garden:

·         Low-Water Native Plants for Pollinators:

·         Low-Water Native Plants for Colorado Gardens: Mountains 7,500’ and Above:

·         Low-Water Native Plants for Colorado Gardens: Front Range and Foothills:



Arditti, J., Elliott, J., Kitching, I. J., Wasserthall, L. T. ‘Good Heavens what insect can suck it’ – Charles Darwin, Angraecum sesquipedale and Xanthopan morganii praedictaBotanical Journal of the Linnean Society 169, Issue 3, 403-432 (2012).

Darwin CR 1862b. Letter 3411-Darwin, C. R., to Hooker, J. D, 25 January 1862. Available at:

Whittall, J., Hodges, S. Pollinator shifts drive increasingly long nectar spurs in columbine flowers. Nature 447, 706–709 (2007).

Friday, December 18, 2020

Seedling Trees, Shrubs, and Perennial Wildflowers Available

Low-cost seedling trees, shrubs, and perennial wildflowers from the Colorado State Forest Service nursery are now available for order, as part of the 2021 Trees for Conservation seedling tree program. The seedlings can be purchased locally from cooperating agencies across Colorado

This year, the nursery is offering a small collection of perennial wildflower plants. Species include Wild Bergamot (Monarda fistulosa), Blanket Flower (Gaillardia aristate), Black-Eyed Susan (Rudbeckia hirta), and Rocky Mountain Penstemon (Penstemon strictus).

Early orders are encouraged as supplies are limited this year. Check out the current inventory here, but remember to make your order through your local cooperator.

The focus of the tree seedling program is to help landowners to meet conservation goals, restore forests impacted by wildfire and other disturbance, reduce soil loss, and enhance wildlife habitat. The program also allows landowners to plant vegetation in areas impacted by tree insects and diseases.

When considering which species to plant, landowners should consider elevation, aspect and soil type. Visit the Colorado State Forest Service website to find your local seedling sale and to obtain local assistance on tree species selection and ordering.