The Best of Red, White, and Blue

Posted by: Alison O'Connor, CSU Extension in Larimer County

To all those who have served our county, are currently serving, or sacrificed their life: Thank you. On this Memorial Day, please know I am very grateful to all of you and your families.

My dad served in the National Guard for over 20 years and my grandpa was a WWII veteran. I am very proud for what they did for our country and proudly fly a flag in their honor. I also love the color combination of red, white, and blue! It's a great threesome.

So...it got me thinking...what are the best red, white, and blue flowers if you wanted to have your own patriotic garden? It turned out to be a really long list, so I'm just highlighting a few below. Feel free to share your favorites in the comments below!

THE BEST OF...RED FLOWERS

Obviously roses are at the top of the list. What's more red than a rose? But red is a hard color--is it more candy apple red? Mustang red? I'm Not Really a Waitress red from O.P.I. nail polish? Red is a very personal color and can be subjective in the eyes of the gardener.

A very good red rose that is fitting with our theme is 'Veterans' Honor' hybrid tea. This rose actually has roots to a special Master Gardener in Larimer County, Roger Heins. Roger is a veteran and worked as a breeder for Jackson and Perkins and this is one of his introductions. Hybrid teas can be fussy, but if you want that perfect red rose, this is this one for you.

Veterans' Honor hybrid tea rose from Jackson and Perkins

If you want to add some color to your summer garden, then plant some zinnias. They are non-stop bloomers, great cut flowers, and come in many colors, including red. In the CSU Annual Trial Gardens, the top zinnia was 'Zesty Scarlet'. Another option is 'Benary's Giant Scarlet'.

Benary's Giant Scarlet zinnia

Runner up red flowers: geraniums, dahlias, tulips, petunias, cardinal flower, anthurium, poinsettias, and amaryllis.

THE BEST OF....WHITE FLOWERS

White is simple. It's pure. White is a neutral and can be paired with anything. Fortunately there are many great white flowers:

Bleeding heart is one of my spring-blooming favorites. It reminds me of my Grandma Stoven who used to tell me a story about each part of the flower. For the life of me, I can't remember! I know it involved two bunnies, a bottle of wine, and button hooks. Bleeding heart loves cooler weather and fades when it gets too hot, but comes back reliably each year. Its cousin, the pink bleeding heart, make a good match in the garden.

White bleeding heart

Iris are another spring bloomer, and iris come in every color of the rainbow. The white bearded iris are absolutely beautiful--a very clean, crisp white. Plus, iris are tough-as-nails. They are drought tolerant and bloom their hearts out every year. Maintenance is minimal and they just need to be divided every few years.

White bearded iris

Finally, an annual that loves the heat and blooms non-stop is bacopa. Looking for a spiller for your containers and hanging baskets? Bacopa is a great choice. This little annual is covered in blooms all summer and doesn't need any pinching or deadheading. 

Bacopa

Runner up white flowers: Shasta daisies, Annabelle hydrangea, cosmos, sweet alyssum, Spring Snow crabapple, and datura.

THE BEST OF...BLUE FLOWERS

Did you know the Pantone Color of the Year is Basic Blue? Yep, so now you can be patriotic AND trendy in your garden, if you plant blue flowers. Blue is a tough color--there's not a lot of true blue flowers, but breeding is getting better and there are many that are close enough. A couple options:

Lobelia. The darling of hanging baskets. The good news about lobelia is that it's being bred to be more heat tolerant. In the past, lobelia would melt with hot weather and all that would be left in your baskets by August were petunias. (Note: there are some very good white lobelia too!) Lobelia blooms all.the.time. 

Blue lobelia. The flowers are just getting started.

My co-worker just texted about love-in-a-mist the other day. She loves it and wants more. With fennel-like foliage, this annual is a great cut flower and will reseed freely in your garden. It does prefer some moisture. After it blooms, the seedpods add additional interest.

Love-in-a-mist (photo from sowtrueseeds.com)

Speedwell (Veronica) is another great blue...with shades of purple. This perennial can range in height from just 12" to over three feet, depending on the cultivar you choose. Pollinators love speedwell and will attract butterflies, bees, and hummingbirds. After the first bloom, cut back the plant to encourage a second (smaller) set of flowers. 

Dark Moody Blues speedwell

Runner up blue flowers: lupine, foxglove, Endless Summer hydrangea, delphinium, Himalayan blue poppy, lily of the Nile, and forget-me-not. 

Red, white, and blue also pairs well with greens, so don't forget those foliage plants! 

Roses are all the rage!

Posted by: Alison O'Connor, Larimer County Extension

I feel that roses tend to polarize people--some think they are amazing and wonderful garden plants (me!) and others feel they are too "needy" and hard to grow. I've had a love of roses my entire life, primarily because my Grandpa Stoven was an avid rose grower, and my dad has followed in his steps. Growing up in Minnesota, roses were not for the faint of heart. And to top it off--Grandpa Stoven grew hybrid teas, which are the ultimate Prima Donna of plants. His favorite was 'Peace', a tribute to the end of World War II and a beautiful bloom.

Peace hybrid tea rose (photo courtesy of Jackson and Perkins Roses)

Most of you know that my patience to baby plants is thin, so hybrid tea roses don't grow in my garden. My philosophy is that if you can't thrive on neglect, you're not a plant for me. But I do have several shrub roses, which I find to be easy to maintain, bloom profusely, and have little (if any) insect and disease problems. They really are easy to grow!

And yes, I know that Japanese beetles are munching their way across Colorado's Front Range, as far south as Pueblo. Roses are one of their favorite hosts, but our state entomologist, Dr. Whitney Cranshaw is evaluating roses to determine if there are cultivars that are less tasty to the hungry beetles. He's been studying this for a few years and has some promising results. For those in infested areas, I realize roses are not going to be at the top of your list, but hand picking can be very effective. Or pick and feed to chickens--they love to munch Japanese beetles and will eat them faster than you can pick them.

Chickens adore Japanese beetles (photo courtesy of New England Habitat Gardening Blog)

Larimer County Master Gardener, Roger Heins, is our rose expert, so I consulted him to see what he would recommend if someone wanted to plant roses. His own garden has dozens of specimens, plus he's been active in the rose demonstration garden at Treasure Island in Windsor. Here's our top recommendations:

Above and Beyond climbing rose (Rosa 'ZLEEltonStrack' PP24,463)
I absolutely adore this rose. And yes, it's a climber, so it needs some support. But what I've found after three years in the garden is that it just needs a little training in the spring and mid-summer. My dad is growing this in his Zone 3B garden north of the Twin Cities. This past winter it had very little dieback and had a magnificent bloom set in early summer.

Above and Beyond in full bloom in June

I have seen zero disease and zero insects, and it's super cold hardy. Height can reach 10 feet, so make sure you give it space! The apricot-flowers bloom in clusters and look like a double flower. It will bloom again later this summer, but the foliage is so clean that's it's just a beautiful plant any time of year. I did quickly snip off the spent blooms, not paying attention to the "rule" of pruning back to five-leaflets.

Above and Beyond in mid-July

Paint the Town shrub rose (Rosa 'BAItown' PP18,060)
Paint the Town is cute as a button, since it's a petite shrub rose that doesn't know when to stop blooming. I have this in my front, west-facing yard, and it gets very little (if any) irrigation. The red blooms cover the shrub all summer and stay a good red, even with the intense sunlight. Topping out in height at four feet (and about the same width), this rose can fit in small spaces if you need some color. The foliage is very dark green and I have seen zero disease issues. My brother has propagated this plant for years at Bailey's and it's on the top of his list too, since he doesn't see any disease issues in the greenhouse. In the photo below, it's planted next to hummingbird carpet, a 'Blonde Ambition' grass, and hopflower oregano. As you can see, it's just a bit taller than each of those. You can remove the spent flowers, if you wish.

Paint the Town shrub rose

Paint the Town flower bloom (just past peak)

Strike it Rich grandiflora rose (Rosa 'Strike it Rich')

Roger said this rose is performing amazingly well in multiple locations, so it's on the list. A grandiflora rose, the blooms are larger (about 4" tall) and have a spicy-sweet fragrance. The blooms are a beautiful orange with hints of pink. Introduced back in 2007, this rose has been a garden favorite for over a decade. Don't shy away from grandifloras...they can replace those high-maintenance hybrid teas with less work. And this rose is very cold hardy too.

Strike it Rich rose (photo courtesy of Destinations, Detours, and Dreams)

Golden flowers make this rose a must for your garden (photo courtesy of Edmunds Roses)

Sunrise Sunset shrub rose (Rosa 'BAIset' PP16,770)

There must be something in the water at Roger's house, because his Sunrise Sunset roses are breathtaking...and big! (Roger tends to both fertilize and water, which might be why his are superior to mine.) This non-stop summer bloomer has bright pink blooms that fade to a paler pink as the blooms age. This plant is truly a show stopper. Cold hardy, disease resistant, clean foliage--what more can you ask for in a rose? 

Sunrise Sunset rose (photo courtesy of Easy Elegance)

Bloom for Sunrise Sunset rose (photo courtesy of Easy Elegance)

Drop Dead Red floribunda rose (Rosa 'WEKcharlie' PP22571)

Described on one of the grower's websites as "jaw-droppingly delicious red", you can envision the bloom before you see the photo. Roger states that this is a fantastic red, especially with the dark green foliage. And it's a red that stays red throughout the entire bloom life. As a floribunda, it will produce clusters of flowers. But if you lust for a good red (like finding the perfect nail polish red), try Drop Dead Red.

Drop Dead Red floribunda rose (photo courtesy of Spring Hill Nurseries)

Obviously there are many roses out there that do well in Colorado gardens. What are some others you love? 

Battling Japanese Beetles

Posted by Lisa Mason, Arapahoe County Extension

If you live in certain parts of the Denver Metro area, you are probably very familiar with this pest. Littleton and other parts of Denver are inundated with this insect starting around mid-June.

Japanese beetle population levels in Colorado. Source: Colorado Department of Agriculture

This invasive beetle has two unique challenges: 1.) Japanese beetles cause damage during the larval/grub stage in turf grass, and adults cause damage by feeding on a variety of landscape plants and trees, and 2.) adult beetles feed on blooming flowers at the same time pollinators and beneficial insects are pollinating those flowers, which limits control options.

Japanese beetles were first introduced in the United States in 1916 and has spread throughout the US via nursery stock. The beetle was brought to Colorado in the 1990s but only recently have populations grown considerably. The larval stage feeds on the roots of turf grass, and the adult beetles feed on vegetation, including popular plants such as roses, crabapples, Virginia creepers, and linden trees. They can feed on over 300 plant types.

Japanese beetle life cycle. Source: University of Minnesota

A Japanese beetle larva. Source: David Cappaert, Bugwood.org

An adult Japanese beetle. Source: David Cappaert, Bugwood.org

You won’t see adult Japanese beetles appear until around mid-June, but now is the time to start planning for their return. Here are some things you can do:

For now and longer-term:

• Keep your plants as healthy as possible. A healthy plant will be able to sustain more damage. Practicing good cultural care will help reduce the stress on your plants.
• Keep turf as healthy as possible, too. A strong root system will be able to tolerate more feeding from grub.
• We are providing a perfect environment for Japanese beetles: well-irrigated turf provides their habitat and a wide variety of plants provides their diet.
• Consider planting other cultivars or plant varieties in the landscape. Research which cultivars are not susceptible to Japanese beetles.
• Be creative with plant selection! Evergreens, annuals, perennials, some vegetables, and many tree varieties are not susceptible to the beetle.
• Research your options for biocontrols and pesticides.
• Choices can be limiting depending on if pollinators are foraging on the same flowers that the Japanese beetles are feeding on. Pollinator-safe options include Bacillus thuringiensis var. galleriae (marketed as beetleGONE!, beetleJUS!) and chlorantraniliprole (marketed as Acelepryn SC).
• Look for plants that do not produce flowers or their flowers bloom at a different time than when the adult beetles are active. For example: crabapple trees bloom in the early spring when adult beetles are not active and other treatments may be an option.
• Remember the label is the law! If you chose to apply pesticides, the directions must be followed exactly.
• For a complete list of control options on foliage and turf and how they affect pollinators, see the Japanese Beetle factsheet.

When the beetles arrive:

Hand picking Japanese beetles off roses. Source: Lisa Mason

• Hand-pick Japanese beetles to your hearts content! You can squish them or dump them in a bowl of soapy water. This effort may seem tedious, but keep in mind each female beetle can lay 40-60 eggs. Hand-picking will also reduce the volatile attractants produced by plant wounding.
• Think twice before using Japanese beetle traps. Research shows that traps can attract more beetles to the area. As they fly towards the trap, they may find new food sources along the way. If you choose to use traps, place them at least 30 feet from any vegetation that the beetles will eat.
• Make sure you have grubs in your turf before treating the turf with products. Checking can save you time and money. Grub damage looks very similar to other turf issues. Try doing a “tug test”. If you tug on your turf and the grass pulls out of the ground immediately, then you have may have grubs that have been feeding on the roots. If the grass is rooted into the ground, you may have another issue.
• If you do have grubs, consider drying out the lawn when the grubs are active. They need well-irrigated soil to survive.

A native bee and Japanese beetles on a rose. Source: Lisa Mason

Are geraniums a plausible solution? Not likely. Research indicates that if Japanese beetles feed on geranium flowers (not leaves), they become paralyzed and rarely recover. However, geraniums are not a very favored host plant and if more attractive plants are nearby, such as roses, Virginia creeper, or lindens, then they would not visit the geraniums.  Also, if they do feed on geraniums, they mostly feed on the leaves, which are not toxic.

Japanese beetles are here to stay, unfortunately. With some longer-term landscape planning and persistent treatment efforts, we can try to disrupt the perfect environment we have created for them. 

More questions on Japanese beetle? The Japanese beetle factsheet is a great resource! You can also call your local county extension office.

Best of luck battling the beetles this summer! 

Cut Flower Challenges

Posted by: Sarah Schweig, Broomfield County Extension

Valentine’s Day is upon us. Love it, hate it, or indifferent, let’s at least appreciate the holiday as an excuse to enjoy fresh flowers! The beauty of cut flowers is ephemeral by nature, and maybe that’s part of the appeal. Still, folk remedies and DIY solutions for prolonging vase life abound. We can explore the science behind these solutions by taking a look at the most common reasons flowers don’t last at home.

Challenge: Insufficient food supply

DIY Fix: Table sugar

This idea here is simple. Plants need sugars to maintain cellular processes. Cut flowers have carbohydrates stored in leaves and stems, and these reserves will be depleted to maintain basic metabolic activity. For flowers that are harvested when fully open, like gaillardia or yarrow, insufficient food supply may lead to early senescence. For flowers that are harvested at earlier budding stages, like gladiolus or peony, insufficient food supply means those flowers may never fulfill their destiny.

Flower food is formulated to provide the ideal amount of sugar (typically glucose), as well as acidifiers (see next problem). However, because sugar is so essential to prolonged vase life and continued development, adding table sugar (sucrose) will do in a pinch.

Challenge: Microbial activity

DIY Fix: Softened water, lemon juice, aspirin, pennies

Unfortunately, plants aren’t the only sugar-lovers living in your vase water. Fresh cut flowers will lose some of those stored carbohydrates where the stems are cut, resulting in a sugary solution that encourages the growth of microbes. While supplemental sugar will support plants, it only exacerbates the microbe problem. Bacteria and fungi block flow of water and nutrients through xylem tissue, and some produce ethylene, which encourages senescence.

The vase life claims of our first DIY fixes are based on the fact that lowering the pH of your vase water will discourage microbial activity. Although hard water tends to be alkaline, chemically softened water contains sodium and should not be used in flower vases. The citric acid found in lemon juice, however, is quite effective and is a common component of commercial floral solutions. While dissolving aspirin in water does lower pH, studies are mixed on whether it has any effect on vase life. Even those studies that report a positive effect on vase life agree that floral solutions are much more effective.

Adding pennies to vase water is based on the fungicidal properties of copper. Pennies have been made from around 98% zinc since 1983, and the copper in pennies is not - and never was - water soluble. We can fully myth-bust this one (satisfying, huh?).

Challenge: Ethylene-induced senescence

DIY Fix: Vodka, gin, whiskey, etc.

Ethylene is a plant hormone involved in ripening and senescence, and thus there is generally an inverse relationship between ethylene and shelf-life. The principle here is that the ethanol, which is contained in distilled spirits, can affect the production of and response to ethylene. Ethanol has been shown to delay maturation in plants in a number of contexts. A study published in HortTechnology investigated adding distilled spirits to water to reduce tipping of paper white narcissus by reducing plant height. At certain concentrations of ethanol, plant height was successfully reduced without apparent toxicity to roots and with no effect on flower size or timing. Ethanol has also been shown to delay the ripening of tomatoes, among other fruits. While there is evidence to support this solution, at-home success would require a high level of precision. Depending on your vase size, the difference between an effective ethanol concentration and a toxic ethanol concentration could be a matter of a few drops!

What You Can Do

There are many practical and effective ways to reduce the effect of ethylene on your cut flowers without the need for laboratory precision. Place them in a spot with good air circulation, away from heat sources. Do not place flowers near your fruits and vegetables, which produce ethylene as they ripen.

Though I generally support the DIY spirit, commercial floral solutions are by far the safest bet for meeting your flowers’ basic needs. One size is not fits all for maintaining cut flowers. Roses and snapdragons, for example, need extra sugar to push blooms open. Sunflowers are highly susceptible to bacterial plugging of xylem tissue and may require a stronger biocide. While it’s tough to get a perfect solution for a mixed bouquet, you can get as close as possible by going with the pros on this one. Floral solutions are readily available and contain, at a minimum, necessary plant food and an acidifying agent to help keep xylem tissue freely conducting water and nutrients.

Another cause of reduced xylem function in cut flowers is embolism. Cut stems under warm water to help prevent these air bubbles from forming. Use clean, sharp tools to prevent crushing the stem tissue. Ensure that leaves growing below the water line, and any fallen leaves or flowers are removed, as this decaying matter will encourage microbial growth.

Eventually, even though you’ve done everything right, you’ll see signs of the battle with the microbes. When water turns cloudy or you notice fuzzy-looking growth on stems, change your vase water and re-cut stems.

How long will your Valentine’s Day flowers last? Try it out, maybe add a penny for good luck just in case, and let us know!

The Plants of Summer

Posted by: Alison O'Connor, Larimer County Extension

Co-workers and friends often joke about my landscape. By now you realize that I adore my lawn, but the landscape plants don't get much attention. My gardening philosophy is that you have to be tough to survive in my landscape. If you need a lot of attention, water or regular pruning, forget it. I've killed A LOT of plants in my tenure in Colorado, but those that have survived have my greatest respect.

And right now, it's tough to be a plant. It's hot, dry and everyone just feels sluggish--including the gardener. But a few are standing up to neglect and thriving. Let's review them:

False indigo (Baptisia australis)

False indigo: Awesome on every level! This has been planted for about six years and this is the first time I really noticed it bloom. Pale lavender flowers on pea-like foliage. The great thing about this plant is it's right where Maple the beagle stalks the squirrels who are trying to eat from the bird feeder, so it gets a lot of paw traffic and abuse. The flowers fade to hardened chocolate brown "pea pods." I cut it back to the ground in the spring.

Sedum

Sedums: I have many sedums in my garden, but I couldn't tell you any of their names, except for the lime green 'Angelina' (not pictured) and 'Autumn Joy' (not pictured). But ground cover sedums are tough as nails, love it hot and dry and fill in gaps. I call them "gentle creepers" and are not at all invasive. I don't really like the flowers, so sometimes I clip them off.

Above and Beyond rose

Roses: For those who don't grow roses because of the myth they are too much work, you should try them! Roses are one of the easiest garden plants, especially the shrub types--a spring pruning job and occasional clipping in the summer. There are several introductions that you can try. 'Above and Beyond' (pictured) is a climbing rose from the Bailey Nurseries First Editions series. It had incredible blooms just a few weeks ago and is ready for another flush. It also has clean foliage and sparse thorns. Other roses I love are 'Paint the Town' and 'Sunrise Sunset'. Some of the shrub roses have great fragrance, so be sure to stop and smell them!

Hopflower oregano (Origanum libanoticum)

Hopflower oregano: This is a wonderful ornamental that can serve as a ground cover or a trailing plant over a ledge. I love the unique flowers tipped in purple. It's in full bloom right now and the flowers will persist through most of the fall and winter, turning a straw color. The foliage is dainty, held on wiry stems.

Smoketree (Cotinus coggygria)

Smoketree: These large shrubs/small trees are very noticeable when in full bloom (pictured above). The flowers look like plumes of smoke. It's versatile, as it can be left as a multi-stem shrub, pruned to a single-stem tree or cut back to maintain the height you want. The first few seasons it died back almost to the ground in winter. I also love the obovate leaves, which are slightly waxy. The best purple color will occur in full sun. Mine is planted under a honeylocust.

Lavender (Lavendula angustifolia) and threadleaf coreopsis (Coreopsis verticillata)

Lavender and coreopsis: I have seen a lot of lavender in landscapes, which is great, since it's a wonderfully fragrant, bee-attracting perennial. It also does very well in dry, high pH soils. Whack it back to the ground in the spring and watch it re-grow. There's a new introduction called 'Wee One' that is pretty much the cutest lavender you've ever seen. As for the threadleaf coreopsis, also called tickseed, it's a reliable bloomer and I love the purple-yellow combination. Tickseed is a no-brainer. After it blooms, cut it back for a second flush.

A world record prickly lettuce plant?

Check out this record-setting prickly lettuce that was growing up through the lilacs! It was nearly five feet tall. It's amazing how I can wear blinders in the garden and not notice these things...

Maple the beagle is off to investigate other summer-blooming plants for the garden!

Learn How to Graft Apple Trees

Posted by: Curtis Utley, Jefferson County Extension

One of the most fantastic horticultural tools discovered by man has to be the art of grafting. The ability to attach a piece of one tree to the branch of another is nothing short of magic. Detached scion grafting was discovered sometime during the first millennium B.C. and contributed to the movement of woody tree fruits out of Asia and into Europe along the silk road (Mudge, K. et al 2009). For Centuries now mankind has been able to perpetuate superior clones of tree fruits by removing a twig or bud from a superior mother plant and attach that twig or bud to a seedling of the same tree species. The result is a replicate of the mother tree growing on the root system of a seedling tree of unknown fruit quality.

Macintosh branch grafted onto Crabapple 

 The practice of grafting is not reserved for fruit trees alone however; many horticultural plants are also reproduced by grafting the most common example is the production of hybrid tea roses. Before the development of tissue culture, the fastest way for a horticulturist to rapidly build up the inventory of a newly discovered rose or other woody plant was by bud grafting. The bud grafting technique is great because the grafter can produce a new plant from a single vegetative bud. If the bud is attached to a large and vigorous rootstock, the plant will often be ready for sale following one season of growth. Grafting is not the only way to produce clones, many plants including roses can be cloned by rooting a cutting. The advantage of grafting is the horticulturist can produce much larger clones and many more of them in a shorter length of time.

Hybrid Tea Rose

Chip bud grafting

Other advantages of grafting include size manipulation, avoidance of juvenility, disease and abiotic stress resistance, damage repair, and the creation of unnatural growth forms. Orchardists and home hobbyists alike have found dwarf fruit trees advantageous. Producing full size fruit on a small tree allows an orchardist the opportunity to plant multiple varieties in the same space it would take to grow one full size fruit tree.  Dwarf fruit trees are also much easier to manage and pick than full size trees. Many fruit bearing trees grown from a seed will not begin bearing fruit until they are mature this is called juvenility. Grafting mature wood onto a seedling tree overcomes this natural habit and allows for fruit production a few years after grafting instead of 15 or more years for a seedling tree to come into bearing.

Production orchard dwarf apple

 Starting in the Twentieth Century research scientists began actively selecting under stalk of horticulturally important crops for resistance against, disease, insect pests, drought, and soil issues allowing these crops to be grown more widely. Even annual crops such as tomatoes and watermelons have been grafted onto hearty rootstocks that have been selected for resistance against soil borne pathogens and greater production. 

Dwarf  limber pine

Grafting also allows horticulturists to produce unique unnatural ornamental growth forms, think of weeping mulberries, weeping cherries, tree form roses, and bonsai conifers.  The last reason for grafting I’ll mention is a technique called inarching. Inarching is a rescue operation orchardists use to save trees that have been girdled by rodents or attacked by a root fungus. New resistant root stock trees are planted directly beside the suffering orchard tree the top of the small rootstock tree is cut off, whittled into a chisel point and inserted (by bending the stem) into a slot cut into the trunk of the suffering tree. When the graft union takes the new rootstock serves as a bridge across the damaged lower trunk or disease ridden root system.

Whip graft

Whip graft budding strip

Successful whip graft union

If you are interested in learning how to graft woody plants I will be teaching a hands-on grafting workshop open to the public on March 31. The workshop will be held at the Jefferson County Extension office located at the Jefferson County Fairgrounds. Participants will be producing their own grafted apple tree to take home and plant. Dwarfing rootstock and a variety of apple cultivars to select from will be provided to participants. This workshop will be repeated April 1 and again on April 2. This workshop costs $20.00 per person, space is limited and reservations are required. 

Register at: http://jeffcohort.eventbrite.com

The Jefferson County fairgrounds are located at: 15200 West 6th Ave., Golden, CO 80401

Citation: Mudge, K. et al. 2009; A History of Grafting. Horticultural Reviews, Vol. 35; John Wiley &Sons, Inc.  

Aw Snap! (Cold snap, that is.)

Posted by: Alison O’Connor, Larimer County Extension

As weather forecasters were predicting our cold snap that we’re currently suffering through, I began thinking about our outdoor plants and wondering if they had hardened off. Others thought the same thing, because a recent listserv had chatter of comparing this cold snap to the Halloween Freeze of 1991. In short, the spring of 1992 proved to be fatal to many trees and shrubs, particularly Siberian elms. 

Nerd alert! Taking photos of plants in sub-zero weather.

I don’t have any elms in my landscape, but I do have many roses. And my curiosity was spurred this week by a woman who emailed asking what she could do to protect her roses. After all, ours were both still blooming and the leaves hadn’t dropped. It seems all of these things (below-normal temperatures, tender green tissue and blossoms) are pointing to one thing—likely major dieback and possibly plant death come spring 2015.

Boy howdy. That stinks. I love my roses.

I consulted with Larimer County Master Gardener and Rose Guru, Roger Heins, on his take on the subject. He expressed similar sentiments, unless people did some extra preparation (he did). I did not. But here are his recommendations for future consideration:

1. Two or three days before the cold weather sets in (and when daytime temperatures are above freezing), deep water your roses. Actually, take the time to water all of your trees and shrubs.
2. After the first two initial temperatures of nighttime temperatures below 30 degrees F, but before a hard freeze (<26 degrees F), pull bark chip mulch (or soil) around the base of the roses. If there is still foliage, don’t make the bark mulch too heavy…wait until leaf drop.
3. If you have roses with long canes (one of my “shrub” roses is over 8’ tall), you can prune the canes back by 1/3 to reduce injury from snow, ice and wind.
4. If you have blooms on the plant, remove these, as they can collect snow and ice and cause the canes to bend or break.
5. After the roses go dormant and lose their leaves, increase the mulch depth around the base of the plants. The rule of thumb is to mulch about 6-8” up the canes. As the roses come out of dormancy in spring, remove the mulch.
6. If you have the time and ability, you can wrap the roses in burlap.

Roses in bloom on 11/12/14.

Remember, snow isn’t a bad thing—and can act like an insulator.  But we generally can’t rely on continuous snow cover through the winter, so extra precaution is a good thing. Because my roses are an important part of my landscape, I will mulch them once I can stand to be outdoors for longer than 30 seconds. And I’ll put it on my schedule to water them once we get those glorious warm winter days. 

Snow can be a great insulator for roses.

Until then, I’ll be anxiously awaiting the arrival of spring to see how this polar vortex affects our landscapes. And keeping my fingers crossed (inside my mittens).

Not a rose! But the red arils on burning bush are beautiful.