CO-Horts Blog

Wednesday, October 25, 2023

Ripening Tomatoes Indoors

by Denyse Schrenker, CSU Extension, Eagle County

The temperatures are consistently below freezing at my house and I am ready to put my gardening tools up for the season. Now I need to decide what to do with all of my unripe tomatoes that have been stuck in purgatory for most of October; not progressing under their frost blankets but also not dying. I can only handle so many fried green tomatoes and green tomato relish and salsa so I sort my tomatoes into those that will ripen off the vine and those that will not.

Some of the green tomatoes I separated for relish.

Tomatoes that are starting to develop a pink blush will ripen off the vine without any loss of flavor; this is called the breaker stage. Tomatoes that are a shiny green and have a white to light green star shape on the blossom end of the fruit have reached the mature green stage. These fruits will ripen off the vine but their flavor will not fully develop - a small sacrifice I am willing to make to eat fresh garden tomatoes well into November. Tomatoes that are a more matte green have not reached the mature green stage and will not ripen off the vine, these tomatoes can be used for green tomato recipes.

Tomato starting to develop blush color.

Once I have separated out the tomatoes I want to ripen, I remove any stems and wash and air dry the fruit on a clean paper towel out of direct sunlight. The dry tomatoes are then placed in layers 1-2 tomatoes deep in a covered box or a container with newspaper or cardboard covering them. I keep them in a dark cool location out of direct sunlight to ripen. Store the tomatoes at a temperature between 70°F and 55°F. Tomatoes stored closer to 70°F will ripen in a couple of weeks and tomatoes stored closer to 55°F will ripen in about a month. Tomatoes ripened below 50°F will be bland.

Washed, dried and ready to store for ripening.

Humidity can cause issues when ripening tomatoes indoors. Too much humidity causes the fruit to mold and too little humidity causes the fruit to shrivel. I typically have more trouble with too little humidity. To help increase the humidity, the tomatoes can be placed in a strainer or blanching pan and then placed in a covered container with water at the bottom. Make sure the tomatoes are not touching the water though. I check the tomatoes every couple of days and remove tomatoes that are ripe or nearly ripe. If I want the tomatoes to ripen more quickly I will add a banana or one or two red tomatoes to the green tomatoes.

Ripening tomatoes indoors does not need to be reserved for last ditch end of the season efforts! I try to pick most of my tomatoes when they develop that light blush color. I find that I get better yields harvesting them at this stage and then ripening indoors because I do not lose as many tomatoes to sunscald, critters, or simply missing them before they become over ripe. It may be the end of the gardening season but I am looking forward to having tomatoes all through the fall!

PlantTalk: Ripening Tomatoes Indoors

Thursday, October 5, 2023

How to Squirrel-Proof Your Bulbs

 by Angela K. Nickerson, Colorado Master Gardener - Broomfield County

I have one neighbor who feeds the squirrels – daily putting out pounds of peanuts for them which I find buried in my garden blocks away. Another neighbor is absolutely at war with the squirrels doing everything she can to discourage them from entering her yard. Me? They are a bit of a nuisance in my opinion, but we are largely friendly with one exception: bulbs. It's infuriating to find my freshly-planted spring bulbs scattered about the yard, the remnants of a bacchanalian rodent feast. However, last year I was determined to outwit the squirrels, and of all the bulbs I planted last year, the squirrels ate exactly ZERO. 

I was a little late in planting my bulbs last fall, and I happened to hear an interview with Dr. Lucia Jacobs, a professor at UC Berkeley who studies squirrel behavior. She said that squirrels watch each other bury nuts, and then go to dig them up in a competitive game of hoarding each fall. They also watch us when we are planting bulbs, and freshly-dug earth is like an X marking the spot for a squirrel. 

I thought a lot about that. And then I devised a plan to outwit my squirrely neighbors. And it worked!

Squirrel-Proof Bulb Planting Materials:

  • burlap yardage or squares

  • landscape staples

  • mallet or hammer

  • trug or bucket for collecting leaves

  • fallen leaves

  • bulbs

  • trowel

1. Plant the bulbs in bunches of 5-6 bulbs (or more depending on what you are planting). Plant them according to the species and at the appropriate depth. Cover with soil. For more information, check out this resource

2. Cover each planting area with a trug-full of fallen leaves. This is a great mulch and insulation. 

3. Cover the leaves with a square of burlap. Secure the burlap to the ground with landscape staples – drive them in with a mallet or hammer. 

Water each spot well, and continue to water on warm days during the winter when we haven't had recent precipitation or snow cover – generally 1-2 times per month on a day that is above 45°F.

Uncover your bulbs in early March (or even February if you planted very early bloomers). Chances are early bloomers will be emerging under the burlap. There's no need to clear away the leaves. They will have begun to decompose over the winter and will provide a little insulation from cold temperatures. The burlap can be washed and stored away or composted.

I planted tulips in these containers and used the same method to cover them. It worked perfectly!

Spring bulbs bring cheer and promise in those early days as we emerge from a cold winter, and they provide early food for some insects as well. Many including daffodils, muscari, and crocus are perennial, and since they aren't dug up year-to-year, you'll only need to cover them the year they are first planted to outsmart your squirrelly neighbors.

Thursday, September 7, 2023

Some Superior Annuals from 2023


Some Superior Annuals from 2023

Colorado State University

J.E. Klett


The following annuals are some of the top picks from both public and industry evaluations.

The public evaluations were held on August 5, 2023 and industry evaluations were held on August 8th, 2023.

Official winners will be posted in late September on our website: https/


Begonia Hybrid ‘Stonehenge Rose Bronze Leaf’ from Benary®

This plant can go everywhere- sun, shade, ground, and containers! It has performed really well and will just keep getting bigger and better until a killing frost. In addition, the breeder is planning to release more of these into the Stonehedge series but with different color onto the market in the next couple of years!

Centaurea ‘FanciFillers Chrome Fountain’ from Westhoff

The silvery-white foliage makes a dramatic statement all by itself but combines well with many other plants. Heat loving, drought tolerant has an impressive uniform and mounding growth habit. It makes a great thriller in potted or hanging combos as well as a subtle touch in ground displays.

Coleus ‘Flame Thrower Sriracha’ from Ball FloraPlant

Dark red leaves are highlighted with a pop of lime green edging that help create a great looking plant. The overall look is enhanced by its very uniform growth habit. It had almost no flowering which is desirable for Coleus since it is primarily grown for its colorful foliage. It thrives in sun and shade.

Dahlia ‘Dahlegria® Apricot Tricolor’ from Syngenta

This Dahlia was a strong favorite due to its impressive combination of dark foliage and large, colorful flowers. Blooms had a unique blend of three colors that really stood out against the very dark leaves. The single petalled flowers were also a magnet for pollinators. The attractive plants had a nice upright growth habit and size that would work well in both the landscape as well as a container.

Lantana ‘Passion Fruit’ from Ball FloraPlant

Selected for a combination of prolific flowering and great multicolored flower with tropical fruit colors, it is also known for having consistent flowering through the season and not cycling in and out of bloom. Dark green foliage really helps the flower colors “pop”. The uniform habit makes a great groundcover for the garden. Plants are very tolerant of heat and drought.

Ptilotus ‘Joey’® from Benary®

Few flowers in the garden have a form as unique as this one. The large conical spikes of feathery flowers have a great lavender color and are very long lasting. The original species comes from central Australia and have thick silver green foliage which helps make it very tolerant of drought and heat.

Rudbeckia ‘Sunbeckia® Luna’ from Flamingo Holland/Bull Breeding

Few plants have the flower power like this one which caught the eyes of almost everyone, even from across the garden. The large flowers are very showy by themselves, but the sheer number of blooms is also very impressive as the foliage is virtually obscured by yellow blooms. The flowers are long lasting for a great display lasting late into the season. Sunbeckia ‘Ophelia’ had the same ranking and had impressive flowers but with a green eye.

Salvia ‘Black and Bloom’ from Ball FloraPlant

Deep blue flowers and a black stem made a great visual combination which was extremely popular. Plants were noted for a larger flower and darker stems than similar varieties. The breeder noted that it was developed to thrive in drought and heat as well as humidity.

Salvia ‘Mystic Spires’ from Ball FloraPlant

This was a standout with its ever blooming, well branched plant and prolific flowering. Its massive and sturdy stems add great substance to the garden. The hummingbirds are nearly constant every hour of the day. They are easy to grow, reliable for color and have moderate drought tolerance (but preform best with fertilizer and regular watering).


You should plan to plant some of these “best of’s” next year in your gardens. They should perform well along Front Range of Colorado and elsewhere.

Tuesday, August 29, 2023

Native Fruits of the San Miguel Basin

 by Yvette Henson

Last Thursday I led a native fruit field trip that we call Native Fruits and Nuts of the San Miguel Basin.  This is a local class I developed and have taught several times over my years with Extension.  I enjoy it very much!  I thought I would share a little about the day and what we learned.

The San Miguel Basin refers to the San Miguel River watershed.  It is also what we call the area covered by my Extension Office, San Miguel and West Montrose counties.  For this class, we visited 4 locations from 9800' feet elevation in the mountains to 6800' elevation along the San Miguel River. At each location, we looked at plants that produce edible fruit and learned identification characteristics. we also talked about poisonous plants and the importance of being sure about your identification. The class was also given a booklet that gives identification keys, plant habitat and uses, including recipes.  We even harvested several kinds of fruit to make something yummy to share with each member of the class.

I will start with a photo of this year's class participants.

2023 SMB Native Fruit and Nut class participants

Some of the plants we saw in fruit were gooseberries (Ribes inerme), mountain currants (Ribes montigenum), Oregon grape holly (Berberis repens), blueberries and bilberries (Vaccinium myrtillus and Vaccinium cespitosum), raspberries (Rubus idaeus), chokecherries (Prunus virginiana), buffalo berries (Shepherdia argentea), lemonade berries (Rhus trilobata) gamble oak acorns (Quercus gambelii) and service berries (Amelanchier alnifolia).

Gooseberries are tart.

Mountain currants are sweet.

Grape holly fruit make an excellent jelly.

These are bilberry flowers.
Blueberry and bilberry fruit look just like tiny versions of the blueberries we buy at the store.  

Wild raspberries are tart/sweet and are so yummy just to snack on. 
They can also be used mixed with other fruit in almost any recipe.

Chokecherries have a distinct flavor that causes your lips to feel puckery. 
They make the quintessential jelly and syrup of the western states.

Leigh Ann, a class participant, picking buffaloberries.

Buffaloberries are full of tart-sweet flavor!  They get sweeter when dried.

Lemonade berries, when soaked in water make a lemony flavored drink. 
They are refreshing to suck on when out hiking.

Gamble oak acorns are low in tannins and so aren't as bitter as most acorns.

Serviceberries are the sweetest native fruit I know of.  They make excellent juice that can be added to other beverages like tea or lemonade to sweeten them.  The fruit is so good eaten fresh!

I hope you enjoyed this picture blog of native fruits.  I would love to know your favorites, and how you prepare them!

Monday, August 28, 2023

Western Slope Willow Workshop

 Posted by Mollie Freilicher, CSU Extension, Tri-River Area

Even though it meant a trip through Glenwood Canyon twice on a rainy day, last week I attended a willow identification workshop in and around Vail. (Spoiler alert - the canyon stayed open and the workshop was great!) 

The workshop was hosted by the Betty Ford Alpine Gardens and the Colorado Native Plant Society and led by botanist Gwen Kittel. Gwen recently published a book on willow identification Willows (Salix) of Colorado: Their Ecology & IdentificationWillows (genus Salix) readily hybridize, which can make identification difficult. I was hoping to demystify willow identification a bit and learn more about the species of willow here in Colorado, and particularly on the Western Slope. Other attendees included CSU Extension Native Plant Master Trainers, consultants, and others interested in learning more about native willows. 

upper side of leaves
Mountain willow (Salix monticola), upper side of leaves

lower side of leaves
Mountain willow (Salix monticola), lower side of leaves

We dove right in at the bike path at Copper Mountain, elevation 9,830 ft. Gwen handed us a vegetative key she developed for willows (and recently revised for her book). She walked us over to our first prospect and asked us to key it out.  After what felt like an eternity and lots of looks at leaf hairs under a hand lens, we arrived at the species, Drummond’s willow (Salix drummondiana)…and then proceeded to do six more at the site.

conifers and willows along a stream
Willows along the bike path at Copper Mountain.

Some of the things we were looking for as we went through the key -

  • Were the twigs pruinose? That is, did they have a waxy coating on the twig surface? 
  • How hairy are the leaves? Are they hairy above? Below?
  • How much longer are the leaves than wide?
  • And much more

We moved on to the second site at Vail Pass, elevation 10,663. Here we had a great comparison of two willows, we had seen at the first site - planeleaf willow (Salix planifolia) and Wolf’s willow (S. wolfii var. wolfii). We could easily see the hairy leaf underside of Wolf’s willow, compared to the smooth hairless, planeleaf willow.

two different shrubs that look similar
It took a close look to distinguish Wolf's willow and planeleaf willow.

underside of leaves
Looking closely, we could see the hairs on the upper and lower leaf surface of Wolf's willow.

We had, for the most part, dodged the rain, but by the time we got to the last stop, the Betty Ford Alpine Gardens in Vail, elevation 8,200, it was pouring and was not going to stop. 

One of the last willows we identified, coyote willow (Salix exigua). Unlike all the other willows we had seen during the day, this one had much narrower leaves.

We persevered along the bike path and keyed out more new species. The keying got mentally easier the more we did it, but physically harder because of the rain. By the end of the day, we had identified 12 species and keyed even more as review. I came away with improved keying skills and more familiarity with and appreciation Western Slope willows.


Friday, August 11, 2023

Flower-Visiting Beetles--not always visiting why you think!


Posted by John Murgel, Douglas County Extension


We get a pretty regular supply of interesting insects coming through the Extension office as folks find bugs in yards and gardens through the season.  This time of year, with many native shrubs and flowers coming into full bloom, is no exception.  Flowers are entomological restaurants, pick-up joints, and crime scenes; well worth spending a few minutes observing while out in the garden (or on a hike!).


One of the common groups of insects that is brought in for identification are termed “flower-visiting beetles.”  The adults are often seen on open blossoms like sunflowers, asters, and rabbitbrush, sometimes in large groups.  These beetles are perhaps sipping nectar, but don’t let this fool you—many are fierce predators of the insect world.


This week a sample of a flower-visiting clerid, or checkered beetle, came in.  Checkered beetles, both as larvae and adults, are almost all predators of other beetles—particularly bark beetles like ips or mountain pine beetle.  This particular insect, though, was in the genus Trichodes, the bee-eating beetles.  Most Trichodes prey on solitary bees and wasps, laying sticky eggs on flowers for bees and wasps to inadvertently carry to nest sites with them, where the eggs hatch and consume the bee larvae and the food the mother bee stored up for it.  A few even accost hosts at flowers and riding back to nest sites in order to lay their eggs near their bee-victims’.  This week’s beetle was, thankfully, less emotionally taxing for a gardener—its larvae feed on the eggs of grasshoppers. 


clerid beetle side view

beetle from top view

Adult beetles not only eat pollen but also hunt a wide variety of insects smaller than themselves.  They are covered in defensive bristles and have powerful, downward-pointing jaws to get the job done.  Their wings are a beautiful blue-purple with red markings, possibly a warning-color mimicry of stinging insects used to deter predators like birds. 


clerid beetle in side view
Look at those jaws!

A lot is going on in the average garden, and much of it is inconsequential to our gardening success.  It sure is fun to watch, though, and not for the first time I am grateful to be the size that I am and not a grasshopper! 




Thursday, July 27, 2023

What's going on with my Veggies?


Today we’ll go into a few problems that you may or may not be seeing in your vegetable garden. I’m dividing the topics into two categories: Biotic and Abiotic. Biotic problems mean those issues that arise due to a biological, or living agent, whether it be insect, disease, or human! Abiotic are those that are outside of the above category, so can be physiological, environmental, or cultural in origin. Sometimes the line can be a little less than distinct between the two as we’ll see in several examples. Let’s get sleuthing.


Powdery Mildew – this can show up on many vegetable garden plants including squash, cucumber, beans, even peas and carrots can be susceptible although at least here in Colorado we don’t see a lot of that. Typically, powdery mildew begins to make an appearance mid to late in the growing season. It is especially prevalent in gardens that are planted closely, and those that are watered with overhead sprinklers. Planting with adequate spacing and watering the soil not the plant are two great ways to prevent the onset of the disease. Powdery mildew is a fungus which grows thin layers of mycelium along the surface of the leaf or fruit (although growth on fruit is less common.)

David B. Langston, University of Georgia,

Be aware that some varieties of squash or zucchini have patterns on them that may look similar to powdery mildew. If you aren’t sure, you can send a picture to your local Extension office or you can look for patterns vs. a more random distribution. Patterns are likely natural, more random is more likely to be powdery mildew.

If your garden succumbs to powdery mildew every year in your cucurbits, your melons, squash, cucumbers etc. there are a few different management options. You can trellis your vine crops and grow them vertically; this improves air flow and reduces ambient humidity. You can also remove the oldest leaves as the plant grows, leaving 5-7 of the youngest leaves at any time. Finally, if summer squash is the disease-ridden culprit in your landscape, you can succession plant, plant new squash about a month after your first crop, rogue the first set out once powdery mildew begins to establish.

Early Blight in tomato and potato

Paul Bachi, University of Kentucky Research 

and Education Center,

A very common disease, the same one that caused the Irish Potato Famine in Ireland, shows up regularly in our tomatoes, especially those that have come from saved seeds if proper sanitation practices weren’t followed. Symptoms can include brown spots on older leaves, brown concentric rings on stems, leathery/black spots on fruit which may drop from the plant. To manage you can plant resistant varieties, be sure to succession plant (at least two years between using the same soil), increase airflow. You can also remove leaves with leaf spot and dispose of them outside your home compost system (landfill or commercial composting facility). Fungicides are rarely effective in a home setting and are not usually recommended.

William M. Brown Jr.,

Tomato spotted wilt virus – Another of the diseases that can impact tomatoes, tomato spotted wilt virus is another common disease seen in home gardens. This disease can be transmitted by an insect called a thrip, when it feeds on the tomato it can infest the plant with the TSW virus. Leaves may develop a cupped appearance, with the bottoms becoming bronze and then dying (leaving brown or black tissue). Most typically it can be seen on fruit with concentric rings developing across the fruit. Fruit is fine to eat but may have a poor flavor. It is best to purchase resistant varieties if you’ve had issues in the past. Pull and dispose of the infected plant.

Brenda Kennedy, University of Kentucky,

Gerald Holmes, Strawberry Center, Cal Poly San Luis Obispo,

Blossom End Rot – Blossom End Rot occurs in quite a few plant species including tomatoes, peppers, cucumbers, zucchini, squash etc.  We often begin to see it as plants first ripen in the early summer and into mid-summer. While it is technically caused by poor calcium in the fruit, this does not necessarily mean that there is insufficient calcium in the soil. Crushing up eggshells or adding calcium to water is not likely to rectify the issue. Rather, it is good to practice good “cultural care” by this I mean you want to make sure you are watering, mulching, and fertilizing the plants as they need to be cared for. Erratic watering and cold soils lead to most blossom end rot issues, so look to your hose and your temperatures before amending with nutrients that are likely not lacking.

Pollywogging / distorted growth/poor pollination
in beans or cucurbits can be caused by several different issues. First off, if you saved your seed but did not control for cross pollination you may have some interesting hybrids on hand. Cross pollination issues will only show up in fruit grown from saved seeds, not from those that cross pollinate this year. Rather it will show up if the seed is saved and planted in the following growing season. However, far more commonly distorted growth is caused by poor pollination. If a bean, cucumber, or zucchini is insufficiently pollinated and continues to grow you may see one half of the fruit mature, but the other remain small.

A good way to ensure distorted growth does not occur is to encourage pollinators throughout your garden. Avoid spraying insecticides unless necessary and grow flowers throughout your space to feed your pollinator friends.

Possible herbicide damage on homeowner tomato

Dr. Joey Williamson, Clemson University.

Curling leaves – can have many causes but the most common are temperature, irrigation issues, and herbicide. Cool and warm temperatures can cause strange growth in leaves. Irrigating too much, too little, or erratically can also lead to leaf curl. If soil dries out too much, or is too saturated, leaves may begin to curl. Finally, some herbicides may cause cupping or curling or other distorted growth. Be cautious when purchasing manure, mulch straw etc. as one particular herbicide, Aminopyralid, can persist in these materials and may cause problems for your vegetable garden growth. If you suspect you have herbicide in your manure or your mulch do a test growth, if distorted growth appears remove if possible. Check out for details on herbicide issues in vegetable crops.

As always, check with your local Extension Office to get more information on this, or any other garden issue. Happy Gardening!

Monday, July 17, 2023

The Amazing Summertime Blues

The backyard entry garden greets people with
native flowers including penstemon and flax.
Posted by: Todd Hagenbuch, CSU Routt County Extension

The only thing that really makes me really blue in the summer is knowing that it is but a fleeting moment for us in the Yampa Valley. This year that seems especially true as the winter snows stayed longer than usual and we had an exceptionally short spring. As a result, our growing season seems even more compressed than usual…which is saying a lot. Those winter snows and spring storms, however, provided water for a spectacular season of blooming native plants, and not only those growing in wild areas.

As part of a landscaping plan that focuses on reducing water use while also providing bountiful color, natives have played a key role in making our family’s yard a sea of red, white, and blue over the July 4th holiday. Rocky Mountain penstemon plays the starring role for blue, with flax and lupine playing a supporting role. Red columbine, white snow-in-summer, and white campion help complete the colors of our flag, with some annuals in pots thrown in for good measure. But it’s the blues that really make a statement.

Penestemon rises above the flax with
snow-in-summer in the background
Rocky Mountain Penstemon (Pensemon strictus) is a long-lived native that grows naturally in sagebrush pastures, meadows, scrub oak stands, and openings in aspen/spruce mixed forests. It has blue flowers that range in shade from light blue to almost purple, with most in my yard blooming a shade of royal blue. Being adapted to many of our local soils and ecological sites, it is an easy-keeper in the garden and requires little, if any care. Pollinators love it, with not only bees and wasps visiting it, but hummingbirds, too, on occasion. It will spread and reseed, so if you don’t have an area where it can run free, note that some control may be needed to keep it in check.

Blue flax (Linum lewisii) has been a favorite of mine for years. In fact, when my wife and I got married 17 years ago (!), we gave packets of flax seeds to our wedding attendees to plant in their yards to remember the event as our colors were pale yellow and flax blue. I love seeing flax bloom in pastures, on hillsides, and along roadways, where it is a favorite reclamation plant. This fine-leafed plant is a perennial, and if you save the seeds and spread them, you can get stands to spread, even though I don’t find it to be aggressive. It is exceptionally drought tolerant and tolerates most of our native soils.

Silver lupine (Lupinus argenteus) is another native that we enjoy having in our yard. Our particular plants are a blue that tends toward lavender, but they can be many shades of blue, purple, and even pink! Lupine are very drought resistant and are liked by all of the same pollinators as the penstemon. Note if you have livestock that propagation of this plant isn’t warranted because it does have toxic principles that make it unsafe for grazing, but in a yard can be a great addition. The fact that it is a nitrogen fixer and helps add nitrogen to our lean soils is a real bonus.

If you don’t have the summertime blues, find a friend who will save you some seed from one of these pollinator-friendly, low-water-use natives; you’ll be thrilled you did!

Lupine in the foreground with penstemon and 
campion filling in behind