first published December 18, 2008

Ah, there’s nothing quite like a kiss under the parasitic scourge of an evergreen…
Most of us know the consequences—good and bad—of standing beneath mistletoe, but I would venture that few really know what mistletoe is? Well, that’s about to change.

Long before mistletoe became the venerable Christmas icon it is today, it was but a plant parasite. As such, it was known only for how it surreptitiously invaded the branches of evergreens and hardwood trees, stole water and nutrients, and left its victims stunted and weak.

There are several species of mistletoe: the traditional Christmas type found in Europe called common or leafy mistletoe (Viscum album) and dwarf mistletoe (Arceuthobium americanum), which can be found right here on the prairies. Common mistletoe has shrubby-looking, leafy branches and primarily attacks hardwoods, while our dwarf mistletoe is more moss-like in structure and prefers spruce and pine. Dwarf mistletoes have also been known to fire their seeds, in a very missile-like fashion, up to 15 metres in search of a good attack spot on an unsuspecting tree. So, now that you know what mistletoe is, let’s take a look at its rich mythological history.

Through the years, mistletoe has undergone an image makeover of unimaginable proportions, transforming from a parasite into a highly romanticized Christmas icon—the kind of feat a dandelion might accomplish if it had a really, really good press agent. Here’s how it all began.

Back in 1200 AD, mistletoe earned the title of being the first organism to be recognized as a plant disease. In doing so, it also became the first disease for which a control was recommended (simply cut off the affected branches). The ancient Greeks ascribed mystical powers to mistletoe, believing that not only could it protect against poisons, but also that it could act as an aphrodisiac and could bestow fertility (one does tend to follow the other). The Romans also saw a lot of merit in mistletoe and decorated their temples and houses in midwinter with sprigs of it to please their Gods.

But the relationship of mistletoe to Christmas really got started with the Scandinavians. In Nordic mythology, mistletoe was sacred to Frigga, the goddess of love. Unfortunately though, Loki, the goddess of evil, carved some mistletoe into an arrow and used it to kill Frigga’s son, the god of summer sun. Well, as the story goes, Frigga managed to revive her son under a mistletoe tree, at which point her joy kissed everyone who was standing beneath it. However, because no good story is without a twist, Frigga decided that as a warning to all, she would condemn the mistletoe to life as a parasite. Of course, she did cut the mistletoe some slack, decreeing that anyone standing beneath a mistletoe tree would be not only protected from harm but also entitled to a kiss as a token of love and peace.

Subsequently, the Scandinavians adopted the mistletoe as a plant of peace. Under mistletoe, spouses could kiss and make up, and enemies could formulate a truce. Also noted was that any young lady standing beneath a mistletoe could not refuse to be kissed, otherwise she could not expect to be married the following year.

So the next time you walk through an entrance at Christmas and cringe as you notice a pair of pursed lips beneath a green sprig, try to think about mythology and romance rather than the parasites…er…make that parasite in the doorway.

Hits & Misses: Tropical vacations & cold shoulders
Question of the Week: Why are the tips of my palm trees turning black?
The Business: Enjoy Gardening, Spring 2009

Pine trees adorned with decorations are not all that unusual at Christmas—unless, of course, the pines are Buddhists. In our house, we always have a traditional tree beneath which we put the presents. But we also have a tropical tree called a Buddhist pine that we (meaning my wife) decorates in an effort to add some extra punch to the Christmas season. However, since Buddha was ascetic and refrained from self-indulgence, we try to keep the baubles to a minimum.

The Buddha’s path to enlightenment probably didn’t include
decorating plants that now bear his name.

Hits & Misses
Hit: Tropical Vacations
Our ornamental grasses are currently taking a bit of a tropical vacation in our greenhouses. They are relaxing in Greenhouse 2 where they enjoy 24°C heated floors, tanning lights (high-intensity grow lights, to be more accurate), all of the drinks they could wish for (via a perfect concoction of water-soluble fertilizer) and a babysitting service (thanks to the meticulous care of our growers). The result is some rather luxurious-looking grass blades. Enjoy the vacation, I say. Spring is only five months away.

Miss: Cold Shoulders
Murphy’s Law states that no heating system shall fail until the arrival of the coldest day of the year. Just as the temperatures plunged, not one—but two!—boilers gave us the cold shoulder at the greenhouse. Thankfully, we have backup boilers, but that didn’t prevent some poinsettias from having to endure a rather chilly night of 7°C temperatures. Being that poinsettias are indigenous to Mexico and Central America, I’m sure they were wishing they were home for the holidays.

Question of the Week
Why are the tips of my palm trees turning black?
Black leaves are all too common this time of the year and are often the result of over-applied fertilizer. During the winter, plants grow very little (if at all) and therefore do not require much (if any) fertilizer. If fertilization of plants is not stopped or drastically reduced, root damage is inevitable and leaf margins rapidly turn black or brown. To correct this mistake, stop fertilizing and start leaching the soil by heavily watering your plant and disposing of the water/fertilizer solution (called leachate) that collects in the tray. If there isn’t too much root damage, the affected plant should recover, albeit slowly.

The Business
Enjoy Gardening Spring 2009
The publishing department has been busily putting the finishing touches on the Spring 2009 issue of Enjoy Gardening magazine. It’s going to print this week and should be available on newsstands by the beginning of February! Recipes, floral designs, how-to’s and plant recommendations—our new issue has it all. Here’s a sneak peak at the cover.

Did You Know?
The dry weight of oil stored in a corn seed is about 5 percent of the total weight of the seed. Macadamia nuts have a whopping 75 percent of their dry weight stored as oil!

“An optimist stays up until midnight to see the new year in. A pessimist stays up to make sure the old year leaves.”
–Bill Vaughan

Jim’s Notebook will be taking a break over the holidays and will return on Thursday, January 8, 2009. Until then, Happy Holidays to all our readers!

Hits & Misses: O Canada & limited availabilities
Question of the Week: Why are my poinsettia bracts turning black?
Science & Technology: Grafting fruits and vegetables

This past week, I had the opportunity to talk gardening with the Torskeklubben branch of Edmonton. Torskeklubben is the Scandinavian Society that provides social activities and education for all those with an interest in Scandinavian culture. Now I’m not a member of the society, but I do have a few ancestral connections. The origin of my surname, Hole, is Norwegian and, according to both a professor of horticulture from Norway and Ken Domier (a favourite professor of mine from the U of A), the proper Norwegian pronunciation of our family name is Hola. My grandmother, however, was born across the Norwegian border, way up in northern Sweden, in a town called Skelleftea. Long story short…my visit with the Scandinavian Society reminded me of an old Norse gem that my mother (with tongue firmly planted in cheek) would repeat to us when we were kids: “Ten thousand Swedes ran through the weeds, at the battle of Copenhagen. Ten thousand Swedes ran through the weeds chasing one Norwegian.”

Har en god jul! (Have a good Christmas!)

Hits & Misses
Hit: O Canada!
It seems that Canadian-made food items are a real hit this year in the Garden Centre. Everything from saskatoon berry spreads from Prairie Berries in Keeler, Saskatchewan to savoury herbs from Farmer John’s in Canning, Nova Scotia have captured the imagination of visitors to the Garden Centre. From far and wide, O Canada, we enjoy our food from thee. (My apologies to those with true patriot love).

Miss: Limited Availability
With global economic uncertainty, many gardeners are wondering if the availability of plant varieties will be affected in 2009. My opinion is that the selection of varieties next year will be as good as the selection has ever been but that most suppliers will grow only to “spec.” In other words, in anticipation of a tighter market, growers are unlikely to give themselves that extra 10% buffer in production as a contingency plan for strong sales. In all likelihood, once a product is sold out, gardeners won’t have the opportunity to wait for the next shipment of plants because there may not be any next shipment…until next year.

Question of the Week
Why are my poinsettia bracts turning black?
I’ll bet the first symptom you actually saw was a wilting of the bracts. Many people automatically think their poinsettia is in need of water when they see wilting bracts, but that isn’t necessarily the case. Poinsettias are extremely sensitive to cold. If they aren’t properly wrapped (in paper, not plastic) or if they are left in a vehicle when it is cold outside, you will first see the plants wilt and eventually the bracts will begin to turn black. That’s why we use heated delivery trucks.

Science & Technology
In the 1990s nearly 60% of Japan’s cantaloupe, watermelon, cucumber, tomato and eggplant were grafted to overcome soil diseases and other pests. Rather than just sowing seeds or transplanting seedlings directly into fields, the Japanese sliced off the desirable fruiting part of the seedlings and then, through the magic of grafting, “knit” that top to other pest-resistant, “decapitated” seedlings.

Did You Know?

Although your plants may not care, there is a difference between a frost and a freeze. A frost is caused by radiational cooling that occurs on a clear, calm night; a freeze is heat loss caused by wind.

Never worry about the size of your Christmas tree. In the eyes of children, they are all 30 feet tall.
–Larry Wilde

first published December 04, 2008

Non-blooming poinsettias are about as likely to ignite the Christmas spirit as a Christmas tree completely devoid of lights and decorations. Both allude to Christmas, but neither is likely to make you spontaneously belt out a carol or two.

Now, the denuded Christmas tree problem can be solved fairly easily with a few decorations and a little sweat, but nothing short of a can of red spray paint will get your poinsettia ready for Christmas if it’s completely green in early December. So if you’ve been trying to entice yours to bloom but have had little success, here is a little primer on how the flowering process works.

The first step involves understanding a bit about the intricacies of the poinsettia flower itself. What many people refer to as the poinsettia flower is, in fact, not a flower at all. The brilliantly coloured “flower” is really just a cluster of modified leaves called bracts. Bracts begin their lives as green leaves but soon lose most of their sunlight-absorbing structures (a.k.a. chloroplasts), which contain green chlorophyll. The bract chlorophyll is then eventually replaced by red pigments, which then lure pollinating birds (primarily humming birds) towards the poinsettia’s true flowers: the yellow, nectar-rich blossoms found in the centre of the bract whorl. That’s the what; now on to the how.

To develop colourful bracts, poinsettias require one key ingredient: several nights of uninterrupted sleep. Poinsettias are categorized as short-day plants, meaning they must have a sequence of short days (and, therefore, long nights) before they will bloom—about two weeks of uninterrupted darkness during the night will do the trick. But remember this: uninterrupted means that your poinsettias cannot be exposed to any light (sunlight or lamps) during those nights. That may sound simple, but I’ve heard more than a few greenhouse growers talk about how a left on light ruined a crop of poinsettias during the critical flower-initiation period. And as little as 20 minutes of exposure to a light that emits 2 foot candles is enough to prevent poinsettias from flowering. It’s an odd unit of measurement, but the concept of foot candles is quite simple: if you stand 1 foot away from 2 lit candles, you’ve exposed yourself to 2 foot candles worth of light energy.

Getting it right
In one’s home, the short-day treatment can be accomplished by putting your poinsettia in a light-free closet for 14 hours per night, for a period of two straight weeks. Remember, however, that although poinsettias need darkness at night, they also need as much light as possible during the day—a little step often overlooked by many. Not surprisingly, the poinsettia found in a closet after a few weeks or darkness wouldn’t even keep Charlie Brown happy.

The “flower” of a poinsettia is actually found at the centre of the colourful bracts.

Once your poinsettias are triggered to flower, they still need sufficient time to colour up and develop their yellow flowers. To achieve this, you need to start the closet treatment somewhere between the end of September and mid October. The rest of your success is really dependant on the light conditions in your home and the amount of clouds in the sky. So, if you’re up to the challenge, give it a try next year. If you’re lucky, the right amount of sun will shine and your poinsettia will bloom by Christmas. If you’re not so lucky, well, you’ll be set for St. Patrick’s Day!

first published November 20, 2008

I think of plants from the agave family as being rather mystical and enigmatic. I mean, really, how else could one describe plants that are edible, that can make you falling-down drunk and that also happen to be a cornerstone of a planned-parenthood program?

So what exactly is this quirky agave family all about? Well, for starters, it’s comprised almost entirely of succulents, a.k.a. fleshy leafed plants that have evolved to withstand the harsh, dry environments of arid regions. Most are indigenous to the southwestern United States and to Mexico, but the southern Canadian prairies are also home to a representative: the spiky-looking Yucca glauca. In fact, my yard has two that I lovingly never water. As appealing as that resilience is, the real value of the plant comes from the biochemical cauldron that’s found beneath an agave’s fleshy stem. That is, of course, if you don’t question the value of what is arguably the most famous member of the agave family: Agave tequilana.

As the name implies, Agave tequilana is the species that provides the raw material from which tequila is distilled. Not surprisingly, Mexico has the corner on the tequila market, thanks to all the Agave tequilana that grows wild in the Mexican state of Jalisco. What is a surprise to most people, however, is this little fact: the worms added to a well-known brand of tequila were dropped into each bottle as a type of “critter quality assurance.” In other words, a decomposed worm in a bottle was a surefire indication that there wasn’t a high enough concentration of “preservative” in the tequila. An intact worm in a bottle meant that the tequila was of a high enough proof. As for the logic behind eating the worm, let’s just say once you find the bottom of a bottle of tequila, it’s not likely that a worm is gonna intimidate you. Or so I’ve heard…

Not a tequila aficionado? Well, don’t give up on the family entirely. Agave tequiliana does have a number of more noble cousins. Agave sisalana, for example, has very strong fibres that are extracted and used in the production of sisal, which eventually finds its way into ropes and carpet. Other species of agave contain high sugar content and are used for food.

OK, that covers the food and drink aspects of agave, but leaves what could be the most intriguing use for this plant’s biochemicals: family planning and medicine. It just so happens that some agave species produce steroids (or at least the precursors of steroidal compounds) that mimic those in humans. As a result, the steroidal compounds in agave are used to manufacture oral contraceptives and cortisone.

So if you’ve been inspired to grow some agaves next year, here’s what you’ll need to know. Few members of the agave family can reliably endure our winter climate; however, Yucca glauca is one that has the fortitude to survive. Just be sure to reward that fortitude with dry, well-drained soil and plenty of sunlight. It’s really that easy.

Yucca glauca

So why not plan on growing a few. True, they aren’t likely to be the showiest ornamental plants in your yard, but I think what’s concealed within their flesh more than makes up for any shortcomings in the beauty department. Tequila and oral contraceptives? Hmm…agave gives whole new meaning to regret on those mornings after.

Hits & Misses: Small victories & girl noses
Question of the Week: I haven’t repotted my Christmas cactus in years, should I?
Science & Technology: *,5,5,∞,10.

Whenever I diagnose a diseased plant, I rely on a vast wealth of information. Some of it comes from personal experience and having grown millions of plants. Other bits live in my library of plant pathology books. A few thousand years ago though, information was not as available as it is now. For example, when the ancient Romans’ cereal crops were dying, they had no way of knowing that the destruction was due to a cereal rust disease. Instead, they deduced that it was the wrath of a God laying their crops to waste. The logical solution then was to create a God called Robigus that would protect the Romans from the dreaded rusts. A special holiday called Robigalia was established to honour the newly minted God, and red dogs, foxes and cows were sacrificed to pacify him (which, I’m guessing, didn’t provide a whole lot of benefit). Thanks to science, Robigus is not as popular as he once was, and we now have a pretty thorough understanding of plant diseases. Gardeners, commercial growers and a few animals are breathing just a bit easier because of it.

Hits & Misses
Hit: Small Victories
As you may remember, I mentioned back in October that our Plumerias (a.k.a. the plants that produce flowers commonly used to make Hawaiian leis) were a smidge reluctant to bloom. Well, two months later, I’m happy to report that about half of them have developed flowerbuds. One is actually in bloom right now and has a fragrance that’s out of this world. In fact, if Plumerias aren’t the most sweetly aromatic flower of all time, I would like to know what is.

Miss: Girl Noses
Some of the potted ferns that we were storing in our coldframe got a little too frosty this past week and turned from an emerald green to an earthy brown. According to the growers, the colour wasn’t as much of a problem as was the horrific smell emanating from the frosty leaves. To be honest, I didn’t find the odour all that bad. As a result, the growers (the majority of whom are women) accused me of having a “boy nose.” Uh, thanks….I guess.

Question of the Week
I haven’t repotted my Christmas cactus in years, should I?

A Christmas cactus has an extremely small root system and can, therefore, be grown in a very small pot for years. However, the soil in that pot will need to be freshened every few seasons. Here’s how.
1. After the cactus finishes flowering, tip it out of the pot and shake off all the old soil.
2. Transplant the cactus into a pot that’s preferably the same size or, at most, one size larger.
3. Water it in.

Science & Technology
*,5,5,∞,10.
No, I didn’t fall asleep at the computer. The above sequence of symbols and numbers is an example of the universal code used for describing flowers. The asterisk means a flower has radial symmetry (i.e. like a pie where each side looks the same wherever the pie is bisected). The first 5 refers to the number of sepals (the green “things” at the base of petals). The second 5 refers to the number of petals. The infinity symbol refers to the number of stamens (too many to count, obviously), and the10 describes the number of carpels (the seed cells). Even in the garden, there’s just no escaping mathematics…

Did You Know?
An amaryllis bulb may produce flowers for up to 75 years!

“Perhaps the truth depends upon a walk around the lake.”
–Wallace Stevens