Who's ready for a for a sneak peak of 2020? I have been very busy getting ready for next year, and I thought this was a perfect time to spill some of my excitement over to you. As the nursery industry moves forward, we here at Christensen’s want to move forward as well. So allow me to introduce you to some of the new stuff out there, as well as maybe a few older items that will be new to us.

(In no particular order)

Physocarpus Summer Wine® Black: Ho-Hum... just another dark leafed Nine-Bark. Nope! These guys clearly stand out and make a mark. The foliage is so much darker and slightly shiny. They stood out across 3 large nursery blocks of plants!

Thuja occidentalis Tater Tot®: The name alone makes it a must-have! I really like the look of this one. Although a dwarf (reaching 1-2’ tall) it is considered a faster grower than a 'Hetz Midget' or 'Danica'.

Pinus Mugo var. Mugo ‘Slowmound’ and ‘Enci’: Although not new to the world these will be new to us. ‘Slowmound’ will eventually reach 4’ tall, but it will take 20-40 years to do so. The ‘Enci’ (which has a normal mugo growth rate) will only reach 2-3’ tall. (As a comparison, a “Mugo” will reach about 20’ tall and P. m. ‘Pumilo will reach 5’ tall)

Sedum takesimense ‘Atlantis’: This one is getting awards from all over – so I had to sneak in what few I could this fall for some division work. I honestly don’t think there are any left as I think the employees around here now have them in their own gardens! I am on the hunt for more! It is a medium sized (6-10” tall) Sedum with incredible serrated cream variegated leaves tinged slightly pink. I am guessing it flowers but who cares.

New Ilex verticillata? Really?? Yep! I am sorry to all the ‘Red Sprite’ aficionados but I have found a new love affair. Ilex verticillata Berry Heavy®. It is a fall and winter showstopper! Huge masses of red berries are spectacular. Also new is Ilex v. Little Goblin® Red: It has extra-large reddish orange berries on a dwarf 3-5’ tall plant. (Both can be pollinated by ‘Jim Dandy’.)

Andropogon gerardii ‘Blackhawks’: Another WOW! This Bluestem emerges deep green to dark purple in the late spring. As the summer progresses the grass gets darker and darker, finally ending up nearly black by fall. At about 5’ tall and very upright this grass looks best en masse. PS Did I tell you that it also has awesome red-purple flowers to sway in the breeze?

I am saving the rest for next year’s surprise!

I still remember planting my first serviceberry with my dad a long time ago – actually, a very long time ago. What struck me most were the many names for the same plant – Amelanchier canandensis, Shadblow, Juneberry, Serviceberry. Somewhat unusual at that time, little did I realize what a high-demand plant it would become. Therein lies the problem. It seems no matter how many are brought in every year we quickly run out. Landscape contractors, designers, and architects ignore so many other great similar-usage plants. Even when repeatedly told we are out till fall dig season, the requests keep coming. There are many good substitutes. In fact, there are many plants that would be better first choices!

Even more shade tolerant than Amelanchier are witchhazels. Larger, fall-blooming, native Hamamelis virginiana could match serviceberry with respect to growth rate and size. H. vernalis and the many crosses of H. mollis and chinensis (i.e.’ Diana, Jelena, Arnold Promise,’ et al.) are slower-growing but offer patio shade and a much greater color range. Native multi-stemmed dogwoods (Cornus florida and fl. ‘Rubra’) give a layered look; same usage but different than the arched or cascading habit of A. canadensis.

Also, a terribly-ignored, rugged, and problem-free group of plants are the Wrinkled Viburnums. In particular, Viburnum rhytidophyllum, Leatherleaf, and V. x rhytidophylloides ‘Willowwood’ are monsters. Achieving height and spread toward fifteen feet, they have an arching habit and are semi-evergreen. These offer spring flower, fruit, fall color, (and winter foliage interest).

A perfect match for Amelanchier ‘Rainbow Pillar’ is Cornus mas ‘Golden Glory.’ This Male Dogwood is very hardy and an early bloomer not usually susceptible to freeze damage. It has exfoliating bark and edible fruit. Its structure provides great winter interest.

Another easy sub for Amelanchier is Viburnum prunifolium, native Blackhaw, large, global, and a great bird attractor. A shrub easily surpassing fifteen feet in height and spread.

So, yes, there is life after serviceberries. I can't promise you that these or any other plants are going to be in stock when you are looking for substitutions, so don't be afraid to consider other options. Let's enhance our landscapes in terms of variety and plant health!

We do this all the time!

We over use, we abuse, we’re in a hurry, and we’re lazy! The landscape/nursery industry is a repeat offender! We have our “go-to,” easy-money plants. On the surface that doesn’t seem to be a bad thing. Almost every contractor has their favorite group of plants; almost every contractor is stuck in some sort of rut! Week after week we get the same list from contractors. Only the numbers change!

Need proof? Recent history provides great examples! Let’s start with the Green Ash. (I hope you don’t need an explanation!) Another great example is the Norway Maple. Our storage field used to have hundreds of Norways of many varieties. It’s “go-to-ness” turned it into an invasive species banned from most cities due to its ability to reseed into alleys and easement areas. The resulting offspring were often not very landscape worthy. Tree growers were left with fields of trees with no market in which to sell them!

Looming on the horizon is the fate of the beloved Callery Pear. The Bradford Pear’s (a.k.a. “Banana-Split Pear”) popularity succumbed to the hyper-popular Cleveland Pear. It’s been the near-perfect tree: Popular, household recognition! Transplanting into most any soil, great form, great bloom quality, and rich, long-lasting fall color!

The overuse of this species has led to outbreaks of Pear Rust, and its ability to reseed has begun to clog open spaces with again undesirable offspring. States and cities have begun restricting its usage. And then there’s probable, correcting fireblight….

What’s next? Will growers develop a truly seedless Callery? Or, what will be the new big seller? Haven’t we learned anything? We don’t need another “go-to” plant. This industry needs good practices and diversity!

We already offer a number of trees that would substitute well for the Cleveland Pear. Some of these are:

•  Acer rubrum ‘Brandywine’
•  Acer saccharum ‘Legacy’

• Acer x freemanii Armstrong’
• Amelanchier laevis ‘Cumulus’
• Carpinus caroliniana

• Cornus mas ‘Golden Glory’
• Ostrya virginiana
• Syringa reticulata ‘Ivory Silk’

• Taxodium distichum ‘Shawnee Brave’

Resist the temptation, don’t be a repeat offender! Mix it up out there!

Ever wonder how Christensen’s stores and maintains trees in "the field" to keep them viable all year long? If you've ever tried to keep above-ground material healthy over a long period of time you know there are challenges to be met. But for the most part, it’s really not that far off from what you do when you plant a tree in a landscape - except we do it for a few thousand trees.

First, we grade out the area where the trees are going to go and then auger holes to place the trees in. After the tree is straight in the hole we backfill it with dirt and lightly pack it down.

Then an irrigation emitter is placed into every root ball. We use two different sizes of irrigation emitters, yellow for trees that are 3” or smaller and black for anything larger. We do an irrigation check on the trees at least once a week depending on the time of year. The irrigation system for the field might run 24 hours a day in the summer, so making sure that the trees get the required amount of water is sometimes difficult. We check the emitters to make sure they are not clogged, that they are spraying correctly, and that they haven’t come off of the feeder line and are flooding the tree.

After the trees are put in the ground we apply pre-emergent to prevent weeds from growing in the root balls and the surrounding soil. We generally do this twice a year. As the year goes on if weeds begin to grow we spray with non-selective herbicide. We add a non-toxic blue indicator dye to make sure that we are only hitting the targeted weeds and not the trees.

We do several other sprays throughout the year to prevent disease or insect damage. For instance, we spray for apple scab in the early spring as the trees just start to leaf out. There's also a scheduled spray to prevent gypsy moth, when the temperature is right. We do other targeted sprays as issues come up. Our nursery is inspected regularly for pests so we can be sure that our material is ready for distribution.

At the end of the season we put tree guards on the trunks to prevent damage that could be caused by roaming rabbits and deer. In the spring we remove any guards that are made from solid material in order to allow the trunk of the tree to stay dry and also to prevent bugs from making a home there.

Lastly, when we lift trees from the field to go on your truck, we carefully re-wrap the rootball with fresh burlap if needed. You can be confident that the trees we store are ready to go on your landscape job, spring, summer, or fall.

Anyone who knows me, knows that I do NOT follow fashion trends. In no way am I a fashionista! In fact, according to my wife I should go on one of those TV shows where the Dad gets a makeover on his wardrobe. On the other hand she knows all of the fashion trends. As a hair stylist, she keeps up on what is hot, what is not, and what is coming back around.

So how are landscape plants like the fashion industry? Well, new plants are constantly being introduced, replacing older models. Other plants fall out of use, some for good reason. We have watched flowering pear go from the tree that everyone planted everywhere, to one that goes on a landscape only rarely. Or how about creeping junipers? Anyone remember those? One of our veteran employees and I were recently lamenting how we used to get a semi-load of creeping junipers almost every week “back in the day”. Now we get them about once a month, and never a full truck load. They are still a great option but it seems that people are planting other things instead. I am betting it won't be long before they come back around.

So plants are like pants. They come into fashion, they go out of fashion, and sometimes they come back in again. And sometimes to be different, you have to look at what is old or out of fashion. For instance, Kolkwitzia (Beauty bush) is a cool plant that no one uses anymore, but should. You see them often where an old farmhouse once stood, or in older neighborhoods like downtown Plymouth. The masses of pink flowers in the spring are really striking and the dark green leaves turn an awesome yellow in the fall. A great plant to use in areas where viburnum or forsythia would go.

So change your p(l)ants! Look at using something old or different and your designs can appear fresh, new, and not like everyone else's. I would still avoid the pear, though.

The first time I saw a plant reversion, I wasn’t sure what I was looking at. A customer had called and said there was a TREE growing out of her Dwarf Alberta Spruce. I had never seen this before, so I had to get my Dad involved. He said it was a classic! One of the buds one year cast off the dwarfing gene and the regular white spruce began to grow instead. I have to admit it was pretty cool looking - the white spruce growing straight and tall - but the customer wasn’t thrilled. The reversion is always more vigorous and would eventually take over the plant if not addressed.

Many of the most interesting and unique plants in the trade come from a spontaneous mutation, like a witch's broom or a variegated sprout. The mutation is discovered, a cutting is taken, and the variety eventually propagated and introduced. Some of these mutations aren’t that stable, and you will see parts of or entire plants reverting to the original form. I would like to point out that this is different than when the rootstock takes over a grafted plant, in that case you can see the growth is coming from below the graft.

Reversion can be brought on by many factors, but environmental stress seems to be a common cause. If you are observant when you are out on landscapes, you can see reversions all the time. That spruce example happens now and again, and loss of variegation is another one that’s fairly easy to find.

So getting back to my “Classic” scenario, my Dad suggested to our customer that we should prune it out immediately, as it was only going to get worse. There was a good chance the plant would survive and eventually fill in around the removed portion. If we didn’t, the reversion would dominate, and the resulting tree was never going to be an attractive specimen. I’m a tree hugger and my Dad’s even worse so of course we recommended trying to save the tree. In the end, we replaced the plant - because of its location and visibility the recovery time was unacceptable.

Each case is a judgement call. If you catch it while the reverted growth is fairly small, a simple pruning may be sufficient to eliminate it. Perennials such as hosta can be dug up, split, and replanted.

So be on the lookout for reversions. They are kind of cool, sometimes a little weird but definitely more common than you think. Take some pictures, share with us what you are finding and I will pull together a follow up discussion on this topic. Remember: Prune out all you can to “nip it in the bud” - if it’s too late replace it - and get a picture for our discussion.

In 2006 Nintendo introduced its new home video game console called "Wii". Six years earlier the Austrian company Redbull introduced the advertising campaign “Redbull gives you wiiings!"  No, “wiiings” is not spelled wrong and it doesn’t really make you fly - my guess is that it mimics its German equivalent “flügel” which has an umlaut above the “u” - or two dots. And it does give you wiiings to soar, if caffeine and taurine work for you. A multi-sensory metaphor unparalleled in its success.

In 1753 Linnaeus introduced his binomial nomenclature system for plants in Species Plantarum. His system consisted of Genus - usually expressed as a noun in the Latin nominative case - and species expressed adjectivally. Simple enough! Then comes along the International Code of Botanical Nomenclature which spells out in rigorous detail its do’s-and-don’t’s.

In Division II Rules and Recommendations, Chapter III Nomenclature of Taxa, Section 4 Naming of species, Article 23 it describes in nauseating detail how to describe one plant within a Genus from another. Its awful! But this finally gets me to my point. On more than one occasion (but not many) a contractor has asked me “What’s with the double i?"

You’re probably going to be sorry they asked.

Using the Genus Viburnum because it happens frequently there, you will see V. x juddii, V. x burkwoodii, V. x sieboldii, et al. The double “i” is used with proper names of people and places giving credit to them as discoverer, propagator, caretaker, or in honor of. For example, in 1924 William H Judd of the Arnold Arboretum planted his hybrid seedling, observing its first bloom in 1929, and naming it in 1934. Viburnum x burkwoodii was introduced by the Burkwood and Skipworth Nursery in Kingston-on-the-Thames, England in 1924. Philipp Franz von Siebold was a German doctor who went to Nagasaki, Japan in 1823 acting for the Dutch government as physician, botanist, and political spy.

It is a simple but tedious process to Latinize English names and places. Adding “us” to masculine names converts an English noun to Latin. For species, inserting a long “i” before the “us” can turn a name into an adjective; similarly in English adding an ”y” ( or “ly”) to the word - “bump” becomes “bumpy” and “friend” becomes “friendly.” Finally, the adjectival species name must be in the possessive or genitive case to show ownership or origination which is “i.” Ergo, “us" becomes “ius” which becomes “ii” (which is pronouced long e, long i). In English we would add ”-’s” as in “Judd” which becomes “Judd’s.”

Hopefully that wasn’t too painful!

The usuage of “-ii” is so rare in English that it makes us stop and take notice. The advertisers of Redbull probably knew this and Linnaeus, by accident, makes us pause to wonder about some of the great contributors to horticulture and to many of the plants we commonly use but take for granted!

Selecting plants that can grow under dry conditions can be challenging. Selecting plants that can grow in the shade can be challenging as well. Finding plants that can grow well under both conditions? Well, that narrows your plant selection down a bit, but there may be more options than you think.

It must be realized that even though a plant is considered drought tolerant, this is only the case once their root systems are firmly established. Until that point, they must be watered regularly. This could take up to a year or more of effort before you can cut back on the watering, but during extended droughts, even established plants need a little help to survive. Using mulch will help by retaining water that is provided by you or mother nature.

Also, there is a difference between shade loving and shade tolerant plants. Some plants that grow well in full sun can tolerate shade, but they will be a bit thin and wispy and not blossom as much. If these plants are to survive, all of their other needs must be met to compensate for the lack of sun.

I will start with shade tolerant varieties. The one selection which, can in some cases, be considered a small tree, is hamamelis (witch hazel). Shrubs include buxus (boxwood), taxus (yew), aronia (chokeberry), and diervilla (bush honeysuckle). Hydrangea quercifolia (oakleaf hydrangea) are surprisingly drought tolerant once established, and of all the shrubs mentioned will tolerate the shade best as they are considered shade loving.

Shade tolerant perennials include campanula (bellflower), hemerocallis (daylily, especially stella d’oro), digitalis (foxglove), geranium sanguineum (cranesbill), liriope (lilyturf), euphorbia (spurge), and phlox subulata (creeping phlox).

You may have better luck with these shade loving varieties. Hosta (plantain lily), ajuga (bugleweed), pachysandra (spurge), vinca (myrtle or periwinkle), tiarella and huecherella (foamflower), hellebore (lenten rose), brunnera (bugloss), lamium (dead nettle), athyrium niponicum (painted fern), and bergenia (pigsqeak).

It may be difficult to plant a shady dry area, but if you put the time in to make sure the plants will be healthy and establish a good root system, I think you’ll do fine. It’s not the biggest plant list, and may not cover every possible candidate. Hopefully you don’t also have deer around making the list even smaller (as well as your hostas).

Designers need to consider many factors when choosing plant material. Evergreen, herbaceous, deciduous? Foliage or flower color, bloom time, preferred growing conditions and so on. One of the most important considerations is plant habit and "ultimate size".

What does "ultimate size" mean?

• Complete in natural development or growth.
• A tree or plant that has reached a desired size or age for its intended use.

Like the old saying goes “Right plant, right place”. Planning and research is vital when evaluating ultimate size to avoid future problems. In addition to knowing how large a given plant may grow, you also should factor in the growth RATE. Dwarf plants aren't always that small at maturity but if it takes them 50 years to get there is that really going to be an issue? On the other hand, popular plants like Colorado Spruce or Weeping Cherry tend to outgrow their siting in a decade or two.

Research is important, and not just on the habit and size of the plant but also the root system, which is often overlooked. For example, don’t plant a Willow tree over a septic tank. Yes, someone I will call ...John Doe... did this to get back at his landlord. Now that might be an example of someone who knew what “ultimate size” would do with the wrong intentions but, planning is everything.

Is it going next to the house? Sidewalk? Driveway? Near power lines? If it’s a row of pine, are you planting them too close to each other making them susceptible to needle diseases in the future? Will the property owner be able to shimmy past the planting bed to get to the building entrance a few years from now? These are just a few examples of what to consider when choosing the right plant.

Above image courtesy of the Arbor Day Foundation (www.arborday.org)

Of all the questions I get about growing hosta the most common one is: which varieties will take sun - and how much sun is too much sun? Many shaded areas get SOME sun and choosing the right varieties for the conditions will be the difference between success and...

Maybe we won't talk about that.

All hostas prefer to have morning sun and maybe some late afternoon sun. It is that midday sun that is the challenge. Sun tolerance, is to some degree, leaf-color related.

Most hosta with whitish variegation will burn in hot afternoon sun. Those that have more green to chartreuse variegation will handle some of that midday sun as long as they are getting plenty of water. You should avoid putting blue hosta in the sun as the blue color is a waxy coating on the leaf and will melt off, turning your blue plants green. Golden hosta WANT sun. If they don’t get enough sunlight they will turn that sickly greenish-yellow chartreuse color. You know the one. Green hosta will typically take some midday sun, and I have found that the thicker the leaf the more sun they will take.

Do you have a shady area that merges into a more sunny area and looking for some continuity? Here is a list of sun-loving hostas to fill in the sunny areas. Remember, soil moisture is key to keeping the plants looking good.