CO-Horts Blog

Wednesday, January 31, 2018

Adventures with Weird Seeds from the Internet

Cassey Anderson- Adams County Extension

All of this warm weather has been starting my gardening itch early. Intuitively I know that we still have months of winter left and that getting the garden going should wait at least another month even for starting seeds indoors. With that in mind, we were inspired in my office to think about what you can start in January. Ornamental plants can take much longer to germinate and grow when started inside, so they are excellent candidates for satisfying that early (or even pre-) season itch.

Coincidentally, last year on a whim we ordered iris seeds off the internet, the seeds were cheap, the picture seemed very unique (and possibly photoshopped so the hue saturation was way off) so we decided to take a try. When the seeds arrived we could not decide if they were actually iris seeds or not, there are definitely a solanaceous seed and a grain seed mixed in the bunch, whether it was tomato or some weedy member of the nightshade family remains to be seen.

The picture from the advertisement for Iris we ordered.
Iris seeds we received, notice how one seed is not like the others...
Since obviously one small batch of iris seeds didn’t seem sufficient we decided to branch out further and found some more unlikely seeds: a set of succulents called bunny ears, once again possibly victims of photoshop as the plants are supposedly vivid baby blue, a color I personally have not seen on any plants. The shape also very unique, a small round stem with two “bunny ears” sticking up.

Bunny Ear Stone Flower  
In an effort to grow something practical we also ordered a few other sedums, particularly a mix of various cold-hardy sempervivum as a way to experiment. If these grow successfully we can plant them in our demonstration gardens

Tiny Seeds!
With the seeds decided it was necessary to create a good setup for starting seeds. So we purchased a heat mat, complete with temperature control, and two lovely LED grow lights. The lights are definitely becoming a conversation starter in the office.

We have hung the lights from our ceiling with some string (with plans to upgrade to a chain at a later date) over the seeding trays which are placed over our heat mat. We got the heat mat on sale so the set up cost us just under $50.

We planted each type of seed in its own flat. The sempervivum seeds are extremely tiny so we just covered them very very lightly. The iris seeds we dibbled in with a pencil (including the errant mystery seeds!). Each tray has been labeled so we can remember what went where.  To wrap it up we covered the whole thing with a clear plastic cover. This retains both heat and moisture to aid in germination.

If we have any success in our office seed-starting adventure we will post later in the year! 

Wednesday, January 24, 2018

Spanish Greenhouse Tour

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

A sea of green...houses
Late last year, I was lucky enough to help facilitate an educational tour of the agriculture industry in Spain. On this tour, we visited many interesting facilities ranging from stud farms, to feed lots, to wineries. For me, one of the most impressive facilities that we visited was operated by a company called Bio Procam. This company cultivates, packages, and markets organic vegetables and subtropical fruits. They crank out over 15,000 tons of produce every year, using farmers that belong to the cooperative, and 25 acres of company owned greenhouse land. They have 26 full time workers that keep their greenhouses going. White plastic greenhouses stretch as far as the eye can see in the area where their operations are located.

Organic produce
43% of the company’s production is cucumbers, tomatoes and avocados each account for 20%, zucchini is 9%, and subtropical fruits are 8% of their total production. 28% of what they grow gets exported to Germany. This is followed by France getting 22%, 21% stays home in Spain, the UK gets 8% and the other 21% is spread throughout the rest of Europe. The success of this company is even more astonishing when you consider that they only grow and distribute produce during the fall and winter months. They have found a niche growing all winter long until April or May, when competition becomes too much.

Bio Procam is committed to being 100% organic. For this reason, everything is grown in the soil, no hydroponic production is done. There cannot be any kind of organic contaminants presented into the system, so the workers cannot live on the site. To keep things clean and working well, they replace the plastic on all of the greenhouses every three years. They have a company that recycles the used plastic for them.

Food for beneficial insects
Bumblebee box
 In front of the vegetable crops, they grow wheat and barley to feed beneficial insects that will feed on aphids and other pests in the event that they arrive in the greenhouse. In the summer, the greenhouses are taking a break from vegetable production, but they grow radish and mustard seed for bio fumigation. These plants will help to rid the greenhouse of things like nematodes and fusarium wilt. They also use sticky traps to control whiteflies, and sulfur dust to keep spiders at bay.


This one is ready to pick
             To pollinate the vegetables, the company buys bumblebees. They live in a box in the greenhouse, and come out during the day to do buzz pollination. Our guide described to us how they harvest the tomatoes when the ends just start to turn red. He showed us how at this point, the inside is already red, as they ripen from the inside out. They use moisture meters to know when the tomatoes need watered. After February, the humidity will be lower and they can prune the tomato plants without the concern of disease. They clean up the bottom of the plant up until the first large branch. The company practices crop rotation, after the tomatoes are all harvested they will plant dutch cucumbers. They purchase all of their seedlings from another great company we toured, Saliplant, but that is another blog…

Monday, January 22, 2018

Avoid Leafy Office Follies

By Carol O'Meara, Boulder County Extension

Keeping green and growing houseplants as office companions?  Spending long days in cubicles and offices can make the hardiest gardener pine for leafy companions.  But not all offices are ready for green thumbs; I’ve heard tales of well-meaning employees locked in battle with supervisors.  One side thinks plants need round-the-clock illumination, the other views plants as energy gluttons draining the world in a vampiric thirst for light.

Before your workplace engages in a war of wattage, clear up confusion on how much, and how long, plants should be illuminated.  Here are a few tips on lighting your foliaged office mates:

Light is essential for plant growth, and for your plants to be happy, keep three things in mind: intensity, duration and quality.  

Intensity, or brightness of the light, governs the manufacture of plant food, stem length, leaf color, and flowering.  Plants kept in low light rooms, as many offices are, tend to be spindly with leaves light green in color. In very bright light the plant would be stockier, with better branching and larger, dark green leaves.

Houseplants vary in their light needs: high, medium and low light. Control intensity of light by placing the plant closer to, or farther from, the light source, keeping in mind that light decreases rapidly as you move away from the source.

Southern windows have the most intense light, followed by eastern and western exposures.  Those receive about 60-percent of the intensity of south-facing windows, while northern exposures receive the lowest light levels of approximately 20-percent.

Duration of light received by plants is of some importance, but generally only to those houseplants that use day-length to stimulate bloom, such as Poinsettia, kalanchoe, and Christmas cactus.  Many flowering houseplants are indifferent to day-length; they respond to other factors so be sure to talk encouragingly with them. It may not inspire the plants to bloom but your co-workers will give you a wide berth; you’ll get plenty of projects done in that time.

  If you’re in a low light office, help your plant survive by increasing the length of time it gets artificial light.  This longer period of light during the day gives the plant more time to photosynthesize, producing food for itself. Comfort yourself with the knowledge that at least one thing in the office isn’t on a post-holiday diet.    

If artificial lights are to be used as the only source of light for growing plants, the quality of light (wavelength) must be considered. For photosynthesis, plants require mostly blues and reds but for flowering, infrared light is also needed. Fluorescent lights vary according to the phosphorus used by the manufacturer. Cool white lights produce mostly blue light and are low in red light. Foliage plants grow well under cool white fluorescent lights and these lights are cool enough to position quite close to plants. Blooming plants require extra infrared which can be supplied by incandescent lights or special horticultural type fluorescent lights.

However, plants require some period of darkness to grow; they should be illuminated for no more than 16 hours. Too much of a good thing is as harmful as too little.  Protect plants by turning off your lights as you leave for the day or put the lights on a timer.


Monday, January 15, 2018

Arthritis and Farming

Arthritis and Farming
By Linda Langelo, CSU Horticulture Program Associate
Arthritis is a debilitating disease that afflicts some 54 million citizens in the United States.  This disease does not discriminate across age, gender or race.  Farmers are among the afflicted.  Being a farmer is a massive job where you need your body to be flexible and in minimal pain to farm effectively. This is not to exclude ranchers and gardeners.  Unfortunately, farmers are at a higher risk for arthritis according to the Arthritis Foundation.  Yes, all types of farming operations and farmers can be in this group.  Beyond the main types of farming operations of corn, wheat, millet and potato farms, the photos below demonstrate the varied types of farms which include tree nurseries, watermelon/cantaloupe farms and organic farming just to name a few. 

Photo Credit: Wikipedia

Photo Credit: Wikipedia

Photo Credit:
Osteoarthritis is the arthritis that most commonly affects farmers and ranchers.  This is when the cartilage –the gliding surface of a joint- is destroyed.  Then, the joint rubs bone on bone creating bony overgrowths called “spurs”.  Osteoarthritis is a heredity disease.  Being overweight can cause this as well.  How?  According to the Arthritis Foundation for every pound you gain adds four pounds of additional stress to your knees.  Worst of all, this translates to six times the pressure on your hips. 
As with gardeners, farmers do frequent heavy lifting and repetitive motions, such as constantly bending and kneeling.  The average age of our farmers in the United States is 58 years.  If those farmers have been bending and kneeling for 30 or 40 of those years, it sets the stage for arthritis.
The best thing to do is go to a doctor or visit a rheumatologist for a correct diagnosis.  Then, there are many options such as exercises which help with strength training, range-of-motion, fitness and endurance.
The Arthritis Foundation states that resting during the day is beneficial.  They also state that a good night’s sleep goes a long way to resting the joints.  Pacing yourself through the day by scheduling and taking breaks.  Changing the type of repetitive motion that you do over a twenty minute period.  This sounds like a lot of work even for a gardener.  It is more about rethinking what you do because you are learning a new habit.  It is not always possible to hire someone or pass tasks along to other members of the family.  Taking the time to rethink and invest in yourself helps you preserve the business you have worked your entire life.  You are worth investing in your health.
If you wish to research more information go to .

Thursday, January 11, 2018

Dormant Oil and Pruning Fruit Trees

This is a tough year.  With dry, warm weather some of our trees are confused.  Many of our fruit trees never really hardened off as reported by our local research station in Grand Junction.  And now many of the buds are swelling on trees in the Grand Valley.   I always tell homeowners to wait to prune their fruit trees later than the commercial orchards so they are closer to spring for the trees to heal.  Growers have to start early due to the sheer volume of pruning they need to do.  And I prefer to spray dormant oil after pruning but this may be one year I decide to do the opposite on my own trees.
Colostate photo-Our goal-Fruit!

I think everyone that growers fruit trees should spray with dormant oil.  This product used to be made from petroleum products but is now usually made from cotton meal seed so it can even be used on organic trees.  Yes, organic trees are sprayed, but that is a whole other article.  This oil is very thick and is only used in winter versus horticulture or summer oils that can be used during the season.  The reason we spray this is to suffocate any insect eggs or overwintering insect adults on the trees to limit pest pressure on the fruit tree in the coming season.  It is an especially good control of aphids.  Make sure the weather is warm enough to spray and that your buds have not broken (not showing any color).  The oil can burn the contents of the bud if open.  Always read the label, it’s the law.  And be sure to cover as much as the tree as possible.  Here is our fact sheet on dormant oil.  It can also be a good control for some insects on ornamental trees as well.

So why do we even prune fruit trees?  Well of course to get better fruit.  Pruning a fruit tree is vastly different than pruning an ornamental or shade tree.  Many of those rules go out the window because with fruit trees you are actually trying to stress them to induce fruiting.  So our goal is to capture enough sun in the fruit tree canopy without sun burning the fruit.  The best shape to do that would be an upside down umbrella.  Now if you do not want to have a tree that looks like an upside down umbrella in your landscape, you can prune to have a central leader with spaced side limbs.  This is an older method of pruning apple trees and cherries also do well with this system of pruning.
Before pruning different types of fruit trees it is important to understand what year wood gives you the fruit.  With peaches the fruit occurs on one year old wood, the new growth from last year.  On apples, it is typically 2nd to 4th year wood but some depends on variety.

With pruning these trees we want to remove 50-60% of the tree if it is young and used to being pruned that way.  Don’t take an old tree and do this, it will stress too much.  Talk to your local agent if you have an older tree.  Here is a link:

Open Center Peach Pruning- Photo by Susan Carter
So young trees have their central leader removed when they have established root systems.  Here is a a diagram from UMN. 

Now back to in their prime trees; when pruning you want to think of the side shoots of the limb together looking like a feather.  So there are very few branches going up or down.  Branches underneath tend not to get enough light and too many branches going in or up can shade other branches and leaves.  But you want a few interior and upright branches to produce future growth and to provide some shade for your trunk and main branches or they may develop sunscald.
There are different types of cuts used to prune fruit trees.  My favorite to help keep the limbs going out instead of up is called a bench cut.  This cut removes the tip of the upward growing branch and brings is back to an outward facing side branch.  This side branch will then become your growing tip and will help keep the height of the tree down and to create that upside down umbrella shape.  Dutch  cuts are vertical cuts that are made on side limbs of mainly apples to induce dormant bud break below.  Something you would never do on an ornamental tree. 
Apple tree with dutch cut- photo by Susan Carter

So to summarize, start pruning and training your fruit trees when young;  Spray with dormant oil prior to bud break;  Don’t  be afraid to remove half the tree yearly;  Know the age of the wood that produces fruit so you don’t remove too much of it. 

Lastly, look for a local training on fruit trees thru Extension.  The Tri River Area offers a fruit tree class as part of their Master Gardener training.  I promise a future article on picking which fruit tree is right for you or should you support the orchards and let them do the labor.  By Susan L. Carter, Horticulture Agent, Tri River Area

Monday, January 8, 2018

How to Save Your Holiday Poinsettia:

Posted by: Amy Lentz, Weld County Extension

The holidays are over, decorations are being put away, Christmas trees are being recycled into mulch…but what about that poinsettia plant?  Should you try and save it for a few months?  Maybe keep it alive until next year?  Or should it be thrown out with the tree?  That choice is one that only you can make, but if you decide to keep it around for a little while longer or even until next year, here are a few tips that can help you be successful in your endeavor.

Hopefully, when you purchased your poinsettia plant, you were careful to get a good specimen; one that had nice dark green leaves, colorful bracts (these are the upper leaves that many people think are flower petals), a tight cluster of yellow flower buds in the center…a real beauty!

See the following article, featuring CSU Floriculture Professor, Steve Newman, offering tips on choosing a good poinsettia plant and keeping it healthy during the holiday season:

With a little extra TLC, your poinsettia plant can keep its colorful bracts for several months and ‘bloom’ again next year. Once the holidays are over, placement of your poinsettia plant will set it up for success. Your poinsettia should remain in a location with plenty of natural light, keeping it away from appliances, drafty areas like a front or back door, heat registers, and far enough away from a window so that its leaves do not touch the glass. Poinsettias prefer temperatures between 60 and 70 ⁰F, so room temperature is ideal.

Throughout the year, you will want to water deeply only when the plant is dry, allowing for the excess water in the pot to drain. Allow the container to dry out before watering again. If you see lower leaves drying up and falling off, you may need to water more often. If those leaves are turning yellow and then dropping, you may be watering it too often. Fertilize your plant every few weeks as needed. Important!...monitor your plant throughout the year for insects such as whitefl, aphids, and fungus gnats – all which can be attracted to poinsettia plants. If you notice a pest, take measures to get it under control promptly.

In late March or early April, your plant may be looking a little sad, but have no fear. It’s time to start shaping the plant and encouraging new growth by cutting back the original stems to a height of 4 to 6 inches, leaving back a few leaves which will allow for additional new shoots to emerge from the nodes of the remaining leaves. You might also see new shoots starting to emerge from the base of the plant. If so, you can encourage their growth by cutting back those older stems which will divert more resources to growing these new shoots, too. You should wear gloves during this process because poinsettias exude a white sap that can cause skin irritations or eye injury.

Two year old poinsettia.

May is a good time to step up your plant into a slightly larger container. Your plant is going to have more shoots and will be larger the following year, so stepping it up will give the roots plenty of room to expand. 

In early June, you will need to encourage some side branching of the stems which may look a little leggy at this point by cutting off the upper 2 to 3 inches of leggy or tall stems, removing the top leaves.

By mid to late June, you should be able to safely move your plant outside in a lightly shaded location. Once outside, you may need to increase the frequency of watering. After a few more weeks (mid July), you can trim the plant again. The last trimming of tall growth should be completed toward the end of August.

Bury the pot in the ground for added stability.
When Labor Day comes in September, it’s time to bring your plant back inside to that bright location in your house. And by mid to late September is the time to think about relocating your plant to a place in your house to condition it to flower…
Poinsettias are a short-day photoperiod plant that naturally start to flower when nights become longer than days (around the time of the Fall Equinox). The shorter days and longer nights signal flower initiation and over the next couple months, usually 8 to 10 weeks, the plant will create the beautiful bracts you see around the holidays. Due to advancements in breeding, many poinsettia varieties on the market today will flower naturally with the length of the night at our latitude and be in full color and bloom right in time for the holidays. However, even a small amount of light during this mandatory dark period can delay this process.

If you want to go the easy route and rely on the natural light and dark cycles, you will need to locate your plant in a spot that gets plenty of light during the day but no supplemental lighting once the sun goes down. If there are streetlights nearby or you flip on the light switch, even for a moment, you could delay or halt the plant’s ability to flower.

However, you can artificially create these long night conditions from late September until you start to see the leaves changing color, usually around the end of November or early December. Everyday, around 5 or 6 pm, cover your plant with a large box that does not allow light to reach the plant or place the plant in a completely dark closet. The next morning around 8 am, remove the box or place the plant back in the light. This will ensure that your plants get at least 14 hours of complete darkness each night and should be repeated for approximately 8 weeks. Once you start to see the bracts changing color, you can stop covering the plant each night.

So there you have it! Sounds easy, right? But, even if it seems intimidating, it might be worth the reward!

My mother-in-law's poinsettia plant is now over 3 years old!
 For more information on the care of poinsettias, see this CSU fact sheet:

Monday, January 1, 2018

Hort Peeves (or a New Year's Resolution?): Stop the Topping!

Posted by: Alison O'Connor, Larimer County Extension

You've heard this before: Stop topping trees! And to be honest, I've seen photos, but I've never really seen the practice, until last week. I've seen plenty of bad pruning jobs, but never topping.
Tree Topping (photo from Northwest Arbor-Culture)
For those unfamiliar with this hideous practice, it's essentially slaughtering the poor tree from the top down, removing large branches and the entire top of the canopy. Some claim it's a "tree haircut" that the tree will grow out of. But no, the tree doesn't "grow out of it" (unlike perms in the 80s) and it always ends up making things worse. Essentially, the trees produces a lot of suckers (water sprouts) that are structurally unsound and prone to damage and breaking. Oh, and the cuts made to do the topping are often large and can lead to disease and insect issues, because the trees can't produce the correct tissues to seal off the wounds.
Water sprout growth following tree topping. All of this growth is structurally unsound and is more susceptible to breakage in storms and can cause tree failure. 
Tree topping is a terrible practice. I should point out that educated and certified arborists never do this. Don't pay someone to do this to your trees.

On the way home from work last week, I saw tree topping in action. I couldn't believe it and immediately pulled my car over to circle back. What I saw was a gentleman in a bright orange shirt hacking his way through a line of trees in his backyard. I cannot be certain if this was a paid service or the homeowner. Regardless, it was horrifying. These trees lined the back fence and were far enough away from the utility lines. The trees didn't deserve this (and it looks like it wasn't the first time they were topped, since I drove by again after the bloodbath).
Yes, I know the dangers of taking photos while driving...I had to do it on the sly. I couldn't stop and just take photos of the man in action!
Here's another shot after zooming in on the photo from the road.
And what do the trees look like after the wrath of a pole pruner? They look awful. And ugly. They do nothing for the landscape. But there's a nice pile of firewood! Oh, and this was done the last week of December 2017...not the most ideal time to prune woody plant material.
Tree topping is wrong. Resolve NEVER to do this.
Let's all make a resolution to stop this practice! It's one that is far easier to accomplish than going to the gym and eating healthier. Happy 2018 fellow horties!