CO-Horts Blog

Thursday, February 28, 2013

Want to grow your own transplants? Well it is almost time to start

If you are anything like me, then the winter doldrums have set in. The recent snow along the Colorado Front Range has lifted my spirits a bit with the promise of drought relief, but I am still anxious for spring. And all of those seed catalogs jamming my mailbox are not helping. Yet it is precisely those catalogs that initiated this post.

Meanwhile, back at your local wholesale greenhouse, the growers are busy sowing, germinating, transplanting, and growing bedding plants for your garden. And with any luck, they will have a grand selection of vegetables and blooming plants for your garden. However, if you want something different or just want the fun of growing your own transplants, it is now time to get started.

Growing your own transplants is not hard nor does it have to be complicated. But there are a few points that you need to remember to be successful.

Choosing the right seed


As spring approaches, the seed racks in most retail shopping centers will start to appear. Of course, most will be very generic with your standard selections of popular tomatoes, peppers, cucurbits, assorted herbs, and flowering plants. Unless you are shopping in an independent local retailer, you are probably only going to find a list common to most locations in the nation or region if you are lucky. It will not be until you shop at a local independent vendor will you find a seed selection with varieties better suited to your specific location. Also, many retailers ignore the fact that the seed inside these packets are living organisms and place the racks in a brightly lit, sunny spot or right smack dab in front of the door, which exposes the seed to drafty blasts. So my advice is to buy your seed from a retailer that specializes in garden plants and make sure that the seed is fresh and packaged for the current year.

One of the many advantages of ordering your seed from a seed catalog is the opportunity to choose different and unique varieties. From the many mail-order (online for you internet geeks) seed companies, you can choose many different varieties heirloom, organic, unusual, rare, or just plain hard to find selections. One of my favorite finds has been the Naga Bhut Jolokia pepper, but that is another story. When I browse and make my annual seed selections, I often choose what sounds fun and has a potential in my kitchen. Make sure that you pay attention to the days to harvest, plant size and other environmental needs, but I typically am willing to try just about anything. Don't be afraid to experiment.

Now that you have your treasures, it is time to think about starting your transplants. Here is where you can show off your gardening skills, even if you don't have any. The key factor here is cleanliness. Here are some of my dos and don'ts:



Use only clean fresh germinating mix. When choosing your germination substrate you always get what you pay for. Buy the good stuff. Make sure that it is mostly sphagnum peat moss with vermiculite or perlite.



Do not use garden soil or leftover potting soil from another project. These are likely contaminated with damping off diseases. Yes I know you can cook it in the oven, but save your oven for cookies. I also only buy small bags. It is easier to keep your germinating mix clean by keeping it closed.


Use clean containers. I like to use the clam shell containers that fresh berries are packaged. They are clean, have drainage, and are instant miniature greenhouses. Ideal for the intense recyclers in the house. To wet the germinating mix, I prefer to add water from the bottom up. I use a mortar mixing tub, but you can use anything that you like, just keep it clean. Uniform moisture is crucial for successful germination. You can keep your germination mix moist with a mist bottle (rinse out the window cleaner please) until your seeds have sprouted and have started to form leaves.



Avoid old and dirty flats. You can re-use flats from earlier seasons, but make sure that they are scrubbed and sanitized. You can mix some regular household bleach with water (1:10) for a nice disinfectant. Make sure that your containers have good drainage.



Choose a warm space for your seed near a sunny window. Most seed needs to be sown and started four to eight weeks before your transplant date. Choose a sunny spot. Bright light is crucial to many cultivars. Read the instructions on the seed pack.


Starting too soon can result in tall and weak seedlings. If you are energetic and willing to make a small investment, artificial light may be in order for you. A simple shop light with fluorescent bulbs is more than sufficient for many applications. However, if you plan to grow your own transplants for many seasons, don't be afraid to invest in a quality grow lamp. You can find these at most independent garden centers or specialty grow shops.



Transplant your seedlings on schedule. Overgrown seedlings are a pain to transplant and separate. Your seedlings will grow faster and be stronger with proper transplanting. Make sure your seedling mix is moistened before you transplant.



Many beginning gardeners make the mistake of using too big of a container for transplanting. In this case, smaller is better. I prefer peat pots, but you can also use just about any container. as long as it is clean. The k-cups with the new single cup coffee makers are perfect. And no, don't grow in the old coffee grounds, Coffee grounds are better when composted.

When the last danger of frost is present, starting to harden off your transplants by gradually exposing them to out doors. Make sure that you don't allow them to wilt, but they will harden off more quickly if you allow them to dry a bit with reduced watering. I am always anxious for spring and often put my plants out too early. Some times I get an early harvest, but sometimes I lose. If you grow your own transplants, you can move a portion out and save some in reserve.

For more information on growing your own plants from seed, please see our Fact Sheet at:

Steven E. Newman, Ph.D., A.A.F.
Greenhouse Crops Extension Specialist and
Professor of Floriculture

Floriculture and Greenhouse Crops Extension

Friday, February 22, 2013

School Gardens Get A Jump On the Growing Season

Posted by Linda McMulkin, CSU Extension-Pueblo County
CMG Sylvia adds the final window to
 a straw bale cold frame

Before window greenhouses and grow lights were available, cold frames were widely used to start plants that would later be planted in the vegetable garden after the danger of frost passed.   Modern technology made growing plants indoors easier and many gardeners gave up their cold frames in exchange for additional garden beds or a new shed.  But a cold frame doesn’t have to be a permanent or an expensive structure. 

CMG Terry explains how to build a
wooden cold frame.  The finished
 structure was donated to a
 local school garden.

The finished wooden cold frame. 
All photos above by C. Hopewell.
Recently, the Colorado Master Gardeners in Pueblo County taught a class on building cold frames in a local school garden.  The goal was to demonstrate how an inexpensive cold frame could extend the spring planting season, allowing for cool weather crops like lettuce and carrots to be planted early enough for students to harvest produce before the end of the spring semester.  Cold frames can be built with old windows and a number of easy to obtain materials, like straw bales, concrete blocks, boards, or door frames.   These temporary structures can then be stacked in an out-of-the-way location when the weather warms, allowing the same space to be used for warm weather crops. 
Sylvia enjoyed the class so much she went home and built a
cold frame for her garden out of a door and door frame
left over after a remodeling project.
Photo by Sylvia.
      In a letter to CSU Extension-Pueblo County Assistant Horticulturist Liz Catt, Christina Hopewell from the Pueblo City-County Health Department said, “I would like to take this opportunity to sincerely thank you and the Colorado Master Gardeners for so graciously volunteering to teach the Cold Frame Construction Class to the UGARDENS Participants.  Without the knowledge and expertise offered by your team, such an opportunity would not have been possible.  The instruction that you provided them on the multitude of different cold frame designs and materials will be critical in the upcoming weeks, and will undoubtedly enhance the sustainability of the community and school garden programs in Pueblo County”.

Tuesday, February 19, 2013

Miracle Plants

Posted by Robert Cox, Arapahoe County Extension

Miracle Plants
(If they survive and grow in Colorado… it’s a miracle)

About this time of year, many Coloradans yearn for spring and the gardening season.  February magazine and newspaper ads seem to target those with spring fever.  

Various trees, lawn grass mixtures, vegetable seed or plants, or plants that repel pests are often hyped.  Some of these ads are, ummm, pretty fraudulent.  Not at all miraculous, such plants and seed mixes can be a disappointment for well-intentioned homeowners.  

Gardeners should exercise common sense - “let the buyer beware” and “if it
sounds too good to be true....” are phrases worth remembering.

In general, avoid responding to plant advertisements that over-hype.   Avoid responding if the advertiser is a marketing or sales group rather than a mail-order nursery.  Post office box mailing addresses rather than actual site addresses may also be cause for skepticism. 

But let’s backtrack just a moment, OK?

One of these over-hyped plants, a tree called Empresstree or Royal Paulownia (Paulownia tomentosa), can become a fun-for-kids (and adults) plant in your backyard.

A Catalpa relative, Empresstree is hyped as a fast grower (“grows to 68 feet the day after you plant it”).    The problem with it in most of Colorado?   It is marginally cold-hardy.  It tends to die back to the ground after cold dry spells in winter (OK, OK, when does that ever happen in Colorado?).  But new shoots from the roots do grow very fast in spring, resulting in a large-leafed, tropical-looking “Jack and the Beanstalk” plant.

Empresstree- not the tree we hoped for, but kinda fun to have.

This die back to the ground and new growth from roots is repeated annually.
So unless you believe that earth warming will continue (or you live in Grand Junction, where Empresstree might actually grow as a tree), have some fun with this unusual “herbaceous perennial”.  Just prune out the old dead stems and allow the new shoots to remain, growing into your "show all the neighbors" plant.

Empresstree - new growth after dieback

OK, I exaggerated the “68 feet of growth” thing a little.  But trust me, Empresstree is a great landscape tree for Colorado...I know because the ad said “as seen on TV”.

Sunday, February 17, 2013

When Junipers Go Bad...

Posted by: Alison O'Connor, CSU Extension in Larimer County's generally not their fault!  But how many times have you seen poor defenseless junipers pruned into shapes like this? (Please note that I am not a fan of junipers in the landscape, but this is just ghastly....and really funny!)  I took this picture on my way to Fort Collins this morning...a route I drive nearly every day.  I was shocked that I hadn't seen it before now.  So like any good plant dork, I pulled over to take a photo.  I'm guessing one of two things:
1. The company (who shall remain nameless) wanted a pineapple-like shrub to welcome clientele.
2. The person responsible for pruning couldn't reach the top.

What do you think?  Anyone else have pictures of plants that have been pruned, um...artfully?

Friday, February 15, 2013

Demystifying the Organic Food Controversy

Posted by: Alexis Alvey, CSU Denver Extension

Back a couple months ago, there was a big hoopla about a scientific article that reviewed the safety and nutrition of organic foods.  This eighteen page article was published in the esteemed journal, Annals of Internal Medicine by Stanford University* and concluded that, “the published literature lacks strong evidence that organic foods are significantly more nutritious than conventional foods.”  Wow, I thought.  Well that is a huge blow to organic producers, food activists, environmental leaders, and anyone else who gives a damn about where their food comes from!  My sentiments were felt even more strongly by others.  For weeks, my Facebook newsfeed was littered with status updates from various people and organizations proclaiming all sorts of things like, “Stanford is a pawn of big ag industry!”, “Academia should DIE!” and “Scientists don’t care about organic growers!!”.  Well, these emotional reactions kind of pissed me off a bit, because, one, I work in academia; two, I consider myself to be a scientist; and three, I went to an Ivy-League school (which isn’t a pawn of big ag industry, as least as far as I know).

In 2012, the CSU Denver Extension Vegetable Demonstration Garden at Harvard Gulch Park produced 750 lbs of organic food, which was donated to the St. Francis Homeless Shelter

So, like the good scientist that I am, I figured I would actually read the article before I made any judgments about the academic integrity of our higher education system.  Most of the eighteen page article was filled-up with nearly three hundred different citations and references, so it didn’t take me too long to read it.  I quickly realized that the authors were not presenting anything new; instead, they were merely reviewing existing studies, synthesizing the information, and trying to draw some sort of conclusion from 240 published studies on organic vs. conventional.  After reading the paper, the biggest conclusion I came to was that more studies are needed on this topic.  As the authors state, many of the studies they examined were “heterogeneous,” and from a statistical perspective, they were difficult to compare.  Furthermore, the authors admit that there have been no long-term studies comparing the health of populations consuming organic food versus populations consuming conventional food (controlling for socioeconomic factors of course).  These types of studies would be extremely difficult and costly to conduct, but are most certainly needed.  Nevertheless, the authors did find some really interesting results –
  • The levels of the nutrient phosphorus are significantly higher in organically-grown produce compared to conventionally-grown produce;
  • Organic produce has a 30% lower risk for contamination with any detectable pesticide residue than conventional produce;
  • E. coli contamination risk does not differ between organic and conventional produce;
  • And, the risk for isolating bacteria resistant to three or more antibiotics was 33% higher among conventional chicken and pork than organic alternatives.

I was also shocked to learn that bacterial contamination is really common in animal food products.  About 65% of both conventionally-raised and organically-raised chicken samples were contaminated with Campylobacter and about 35% of both were contaminated with Salmonella.  49 – 65% of pork samples were contaminated with E. coli for both conventional and organic.  Ewww.  How disgusting.  I will now be even more vigilant about cooking my meat, and will be more empathetic towards my vegetarian sisters.

Veggies growing at the CSU Extension - Jefferson County office

As I sat that night in my quite apartment munching on some hummus and baby carrots (and yes, the carrots were organic, but the hummus was not), I began wondering why people get so upset and so angry when they are presented with new scientific evidence that challenges their views and beliefs?  Perhaps the organic vs. conventional debate, like so many other issues in horticulture, can’t be boiled down to mere facts.  It is the passion, emotions, and values that underlie an issue that really motivate and move people.  There are so many disparate reasons why people buy or grow organic or conventional food that knowing the amount of phosphorus in an apple isn’t going to change people’s actions.  What about the apple grower who decides to use only organic pesticides because he is worried about chronic exposure to organophosphate pesticides?  What about the single mother on food stamps who is relieved to find conventional apples on sale for fifty cents a pound?  Is one person right and one person wrong?  There are many reasons why an individual may buy or grow organic or conventional food, and we should find it in our hearts to be nonjudgmental and open to all different viewpoints and choose what is best for us as individuals.

*Smith-Spangler et. al. Are organic foods safer or healthier than conventional alternatives? A systemic review. Ann Intern Med. 2012; 157:348-366

Tuesday, February 12, 2013

Piñon pines under attack in SE Colorado

Posted by:  Linda McMulkin, CSU Extension-Pueblo County

In southeastern Colorado, Pinus edulis (Piñon) and Juniperus monosperma (One-seed juniper) are part of the native landscape and we often look at them as indestructible.  Unfortunately, our piñon are under attack by an insect that most of us didn’t know much about until two years ago.  The damage caused by piñon pitch mass borer in natural areas and local landscapes has been devastating.        
I’ve personally visited more than 30 sites in various parts of Pueblo County where one or more piñon showed symptoms of piñon pitch mass borer (Dioryctria ponderosae).  The Colorado State Forest Service office in Cañon City reported that they have seen infested pines in Fremont County and a local rancher says he has found evidence of infested piñon in northern Huerfano County.  While the problem is primarily on piñon, I’ve found evidence of the insect on Ponderosa (Pinus ponderosa) in landscapes in Pueblo West.  In the Midwest, the European native Scots (Pinus sylvestris) and Austrian (Pinus nigra) pines have also been attacked, but we haven’t seen piñon pitch mass borer on those species in Pueblo as of early 2013. 
Many pines are overwatered in urban landscapes, making them more susceptible to pitch mass borer due to excessive succulent growth or bark cracks.  And while many of the plants I’ve examined are in landscapes, others are in unirrigated natural areas.  Those trees are likely weakened due to the continued drought in our area.  
Fresh and dried pitch on Pinus edulis
Photo by CMG Sylvia Sanchez.

Infested trees look stressed, with thinning or browning needles.  The most noticeable sign of infestation is pinkish pitch on the trunk or larger branches, often near the branch crotch.  The pitch is spongy and sticky, about the texture of chewing gum on a warm day.  Pitch will drop onto lower branches and dries to a cream color. 
The insect, a small moth whose larval form is a wood borer, is responsible for reduced vigor and tree death.  The adult insect is small and may be unnoticed in most landscapes.  It is a moth, about one-half to three-quarter inch long, grey- brown in color with white markings.  The adult emerges from the infested tree June to August, leaving a small hole in the bark.  Eggs are laid on the bark, often near wounds, pruning cuts, or the crotch of the larger branches.  The larvae, a tan worm with a brown head, tunnel under the bark and feed on the vascular tissue of the tree.  
Pitch mass borer larvae and fresh pitch.  Photo by: 
Dr. Whitney Cranshaw,  Colorado State University,

            An interesting characteristic of this insect is that the larval stage can last for one or up to two years, depending on weather conditions.  Eggs are laid from late June to August and hatch from one to four weeks later.  The larvae go through four molts and then pupate in a pitch and silk-lined chamber in their tunnel.  In Nebraska, the life cycle can take 14 to 24 months.  Dr. Whitney Cranshaw, CSU Entomologist, reports that the life cycle of Dioryctria ponderosae in Colorado is at least 2 years. 
             Officially, once the larvae are under the bark, chemical controls are ineffective, but you can try to stab the larvae inside the tunnels with a flexible wire.   Unofficially, local nurserymen and gardeners report that soil drench products containing Imidacloprid, labeled for some types of deciduous trees borers, has been effective on pines.  No research on the effectiveness of this chemical on pitch mass borer has been published and the insect is not listed on product labels, so there is no guarantee that it will be effective.  But I stopped by to check a couple of tress that I know were treated with Imidacloprid last summer and they show no additional signs of damage.  Actually, they look great, which I didn't expect after what I saw last spring.

Thursday, February 7, 2013

Gardening for Our Winged Friends: Butterflies and Hummingbirds

Posted by: Kurt M. Jones, Chaffee County Extension Director

Here in Colorado we are lucky. Not only do we have many species of butterflies that frequent our area, but we also have several types of hummingbirds that visit Chaffee County. Many of these creatures may simply stop in our yards for a break on their way up to the high country. However, if you want to encourage them to stick around for a while, there are a few steps you can take. To set up a butterfly and hummingbird garden, keep a few simple thoughts in mind.


First, realize that each life stage of the butterfly has specific needs. The food sources for immature stages (various caterpillars) and adult butterflies can often be very different. Food supply is critical and so is the physical environment they each need.

Since Colorado is prone to high winds at certain times of the year, it is helpful to provide shelter from wind for butterflies. Using windbreaks or a sheltered area is a good start. It is also important to know that most butterflies have specific host plants on which they develop.  Monarch butterfly caterpillars will only develop on milkweed. Black swallowtails feed only on parsley, dill and related plants.

The food supply for adult butterflies usually consists of nectar, or sweet liquids, produced by flowers.  Some types of flowers produce more nectar than others and even flower color can attract or deter butterflies. Some of the more common butterflies in Colorado and their favorite annual flowering plants on which adults feed include:

Painted Lady butterfly on Agastache
(photo by Curtis Utley, Jefferson County Extension)
  • Two-tailed swallowtail (geranium)
  • Western tiger swallowtail (zinnia)
  • Monarch (cosmos)
  • Painted lady (cosmos, zinnia, and others)
  • Clouded sulfur (phlox, marigold)
  • Orange sulfur (marigold, zinnia)
  • Silver-spotted skipper (zinnia, sweet pea)
  • Checkered skipper (verbena, aster)

Keep in mind that the caterpillars (immature stages) of butterflies can be destructive to desirable plants.  For example, as mentioned earlier, black swallowtail caterpillars will munch on dill, parsley, fennel, and carrot. So be careful where you plant these if you want them for your dining room table instead of for caterpillar food. The same applies to the European cabbage butterfly which likes broccoli, cabbage, and other members of the mustard family.


There are several types of hummingbirds that live in Colorado. The most common is the broad-tailed hummingbird. Others that we may see from time to time include rufous, calliope, and black-chinned hummingbirds. During the summer we see hummingbirds most frequently in the foothills and the mountains, because they nest in these areas.

It is a little harder to attract hummingbirds to our gardens than it is to attract butterflies. First of all, the garden must be visible to them from 30 to 50 feet overhead. The colors must be vivid in order to catch their eyes on their migratory trips from mid-April to mid-May and again from mid-July through September.

There is a long list of flowers that are attractive to hummingbirds. Some annuals that you might have success with include geraniums, verbena, dianthus, vinca, morning glories, salvia, and smaller-flowered petunias.

Here are some other tips that may help you in luring butterflies and hummingbirds to your garden. Plant several separate gardens to minimize competition between butterflies and hummingbirds. Plant masses of color closely together to create islands of bright color. Annuals work particularly well for this. Plant some of the annuals that attract both butterflies and hummingbirds, such as geranium and verbena. Plan your garden so that some flowers are blooming all summer. Timing is everything. And, lastly, minimize the use of harsh pesticides if at all possible. Not only will they harm many butterflies and hummingbirds,
but they may also kill spiders and insects that are also eaten by hummingbirds.

Finally, Utah State University just released a terrific publication titled "Gardening for Native Bees and Beyond."

Tuesday, February 5, 2013

Colorado Garden and Home Show kick starts spring fever

Posted by: Carol O'Meara, Boulder County Extension

You wouldn’t expect a garden of perfumed flowers and lush greenery in the middle of February, but at the Colorado Convention Center in Denver, a landscape of beauty is waiting for you just inside the door.

At the 54th annual Colorado Garden and Home Show, February 9 - 17, ponds, waterfalls, and foliage celebrate the rarefied air of the Rockies.  Soar with the 5,500-square-foot “Flowers and Flight” entry garden, featuring air and space-themed gliders, a Piper J-3 Cub, DK-1 “Der Kricket,” Velocity XL, and Flying Machine courtesy of the Wings Over the Rockies Air & Space Museum.

Visitors to the region’s largest home and landscape show will be treated to lush gardens, do-it-yourself tips, and expert companies ready to help you wade through home improvement projects. 

Garden after garden fill the 400,000-square foot hall, showing off the natural landscapes and urban getaways that are possible for your yard.  Landscapes add to home investment, adding between seven and twelve percent to the value of a home, according to a Michigan State University study. 

But if you’re looking for innovative ways to improve your home’s value, chances are one of the 700 companies from 25 states and Canada can help. They’ll introduce new technologies and trends in landscaping, gardening, energy-efficient heating and cooling products, window treatments, siding, flooring, lighting, indoor and outdoor fireplaces – in short, everything you need for remodeling kitchens, getting new roofing, or redoing a bathroom.

Headlining the wish list in 2013 is tips for being water-thrifty without compromising gorgeous gardens.  And environmentally savvy consumers are clamoring for sustainable products, so exhibitors are showcasing products made from recycled materials, renewable energy sources, or energy conservation.

Look for the Colorado State University Extension booth, where tips for making the most of a water wise landscape are showcased.  From broiling western spots to cool, shady northern yards, the Colorado Master Gardeners are ready to help you with information on plant selection, placement, and irrigation.  Leave time to browse the Plant Select portion of the CSU booth; the plants on display are proven best for Front Range gardens.

In an effort to help area food banks, the Colorado Garden & Home Show will offer $2 off admission to attendees who present a nonperishable food item at the ticket window at the Colorado Convention Center. All of the food gathered will be distributed to local area food banks (discount is not good with any other offer).

For a complete list of the show’s schedule, check out their website at

What: Colorado Garden and Home Show
When: Feb. 9-17, noon to 8 p.m. Monday through Friday; 10 a.m. to 8 p.m. Saturdays; and 10 a.m. to 6 p.m. on Sundays.
Where: Colorado Convention Center, 700 14th St. in Denver.
Admission: Admission is $12 for adults and $10 for seniors; children 12 and under are free.
Information: 303-932-8100;