Boxwood Issues

If you can handle the anger, frustration and disappointment of being a Kansas gardener long enough, you'll eventually receive the practical equivalent of a PhD in horticulture or plant pathology.  That wisdom, of course, comes in bits and pieces bestowed by innumerable little plants who came into your garden wholesome and happy from their nursery greenhouses and then exited from your well-intentioned care  in a brown and unhappy state.  Now, I'm not claiming that I am solely and personally responsible for all the plants that have expired in my garden despite or because of my efforts.  I'm certainly aided in that regard by ferocious winds, summer droughts, frigid winters, rabbits, deer, pack rats, and the occasional insect pest.  But when push comes to shove, I can usually point to a lack of knowledge or foresight that resulted in my abetting the actual criminals.

My hard-won garden lesson this year comes in the form of my front boxwood hedge, formed 8 years ago from twelve tiny plants of Buxus microphylla koreana 'Wintergreen'.  I planted this hedge around the curve of a driveway circle in front of the house to both define the circle when it was just a dirt and later a gravel path, and also to block a little Sha energy from the front entrance (some attention paid to Feng Shui never hurts).  These grew well for the first 6 years, but last year, in arguably the snowiest and coldest winter of the past decade, one bush in the center of the group had some stems which yellowed and died back. I wasn't sure of the cause, but a large snow drift did cover the center of this hedge for a couple of weeks in January, 2010, so I surmised it might be a little winter damage.  I treated it by some judicious pruning of individual branches and assumed new growth would cover the defect.

This year, after a second snowy winter, perhaps even colder than last, several of the center bushes have the same damage visible, as you can see from the pictures above right and below.  The picture below was taken just as the last remnant of another snow drift was melting, and as you can see, the damage is in the center of the hedge, right at the point where the highest drift occurred.  A little Internet research tells me that since it is unlikely that insect or fungal damage would occur only in the center bushes, this is probably just a classic case of winter injury to boxwoods.  Symptoms include yellowish, reddish, or colorless foliage, dead branches that occur particularly in the middle and apical parts of the crown, and loose bark or cracks in the stem, all of which fit my hedge.   Winter damage in boxwoods is exacerbated by allowing them to suffer in dry summers and  to go into winters without applying supplemental water, and I'm guilty of that since I haven't hand-watered these since 2005.  And it can be minimized by spraying with anti-desiccants in November and January, and my no-maintenance goals caused me to be guilty of that gardening transgression as well.  Guilty, guilty, guilty-as-charged.

Admittedly, hardy boxwoods are new to landscapes in the Flint Hills, and this hedge is an experiment to see if Global Warming has allowed us to shift climate zones.  After the severity of the past two winters, of course, I'm not sure that even Al Gore still believes in Global Warming.  I planted these because I like broadleaf evergreens more than conifers for Kansas landscaping, particularly since bagworms seem to be particularly plentiful in this area for gardeners who forego pesticides. I knew the constant cold dry wind in winter would be a challenge for the boxwoods, as would the full sun exposure of this area.  'Wintergreen' is one of the most cold-hardy of its cousins, as well as being the variety recommended to stay more green than bronze in winter so I thought I'd give it a shot. I also grow 'Winter Gem' and 'Green Mountain' in more protected areas as specimen plants and they seem to be doing alright where the wind isn't so dessicating and where the snow doesn't pile up.

So, for this hedge, instead of letting it grow au natural, unpruned, as I have in the past, this year I'm going to give it a second chance by pruning it to half-height, which will get rid of most of the damage and even out the topline.  I'll keep it watered better if it is a dry summer, but I refuse to stoop to spraying anti-desiccants.  the survival of these boxwoods is certainly dependent on thin ice, literally and figuratively.  Further bad winter damage in the near future and these babies get shovel-prunned in favor of something more resistant to the whims of Kansas.  Like a stone wall. 

Linseed Learnings

In a recent post I recommended the use of boiled linseed oil for the annual care of wooden tool handles and in doing so, and making sure I was conveying correct information, I got quite an education on linseed oil.  Here are ten facts about linseed oil that every gardener should know:

1. Linseed oil is actually flax seed oil.  I always wondered what a "lin" plant looked like.  Flax, I know. As an old man who hates burping  the fish oil recommended by the doctor, and who has been taking flax oil (also high in the Omega-3 fatty acids) instead, I think it's important to know that I'm preserving my arteries with the same crap that dries sticky and yellow on my wooden handles. Now the question is, should I, as a frugal gardener, save money and just drink from the $5.00 linseed oil can instead of buying the bottles of gel-caps?  Maybe the "do not take internally" text on the Linseed Oil can is a message in itself.

2.  The particular characteristic of linseed oil that makes it useful for our purposes is that it is a "drying oil" (along with tung, soybean, safflower, and poppy)  that polymerizes in combination with oxygen into a solid form.  It also shrinks very little on hardening and penetrates wood well. It is a traditional finish for gun stocks, cricket bats, billiard cues, and surfboards.

3.  In Europe cold-pressed linseed oil is eaten with potatoes and Quark cheese (a bland type of cheese).  The "hearty taste" of linseed oil supposedly offsets the bland taste of the cheese.  That means that a really terribly bland meal is made to taste like cardboard and is now considered edible.

4.  Linseed oil is water-repelling, but not water resistant.  Water penetrates a linseed oil finish in minutes and water vapour bypasses it completely.  Garden furniture treated with linseed oil may develop mildew.

5.  Linseed oil is a common carrier in paints, puttys and varnishes due to its drying properties.  Okay, no surprise, everybody knows this one already.

6.  Linseed oil was once used commonly to bind wood dust and cork particles into linoleum, a floor covering invented in 1860.  The use of real linoleum has declined as more durable PVC floor coverings have been developed.

7.  Linseed oil used to be boiled to cause it to begin polymerization and oxidation, thus making it thicker and shortening drying time.  Today most "boiled linseed oil" products are a combination of raw linseed oil, petroleum-based solvents, and metallic/catalyst dryers.  Modern boiled linseed oil is not edible, so stop chewing on the handles of your garden tools. 

8.  There was a National Linseed Oil Trust, formed in 1885 and based in St. Louis, that protected "linseed" interests in the United States.  It was dissolved in 1920 under charges that it violated the Sherman Antitrust Act.  As I read the history, essentially this was a linseed oil "cartel" that was accused of colluding to raise linseed oil prices.

9.  The polymerization of Linseed oil is an exothermic reaction, which creates a cascade of  heat buildup and make linseed oil-soaked rags particularly likely to cause spontaneous fires.  Always. always spread these rags out to dry before disposal and never just throw them into a trash can wet. 

10.  The primary world producers of flax seed  are Canada and China.  The United States was fourth in production in 2007 and almost all of the crop is from North and South Dakota, Minnesota, and Montana.

So, that's the short story of linseed oil.  Now that I know more about it, and have learned that it is one of the worst protectants of the natural oils against water, I probably need to choose something else to protect the handles of my garden tools.  Tung oil, for example, is more resistant to water, doesn't yellow with age, and would be a much better choice as a protectant.  But that brings up a whole bunch of other questions about using local versus imported substances (not many Tung nut trees are raised in the US) and the environmental effects of growing flax in mass quantities and on, and on.  Being a world-conscious consumer is so exhausting.

Spring?

Well, it was almost Spring.  For a moment.  We've had a few days in the last few weeks where it was warm enough that I had a decent start on cleaning up the spring beds.  In fact, Saturday I cleared the last bed adjacent to the house of the debris of fall and it is ready for mulch as soon as the last of the daffodils break through.  Then, yesterday, this:

Just God's little way of reminding me that Spring doesn't officially begin until the vernal equinox; March 20th, 2011, at 7:21 PM EDT.  I fear not for the daffodils, but it probably doesn't do the new red poppy foliage any good.

Shrubs for Your Soul, cont.

  Continuing with an earlier post (also published in a new online gardening magazine titled Toil the Soil at Bestgardenblogs.com) discussing early flowering shrubs that are well-adapted for the Great Plains.  Suggestions 1 through 3 were for  Forsythia sp., Magnolia stellata, and Lilacs, and we continue now with:  

'Arnold Red'

Honeysuckles:  Honeysuckles are great performers in Kansas gardens, and I’ve seen decent success with either bush-type introductions such as Lonicera tatarica ‘Arnold Red’ (blooming in late April in this region), or with the more vine-like and later-flowering Lonicera japonica cultivars such as ‘Hall’s Honeysuckle’. I grow the latter on a woven-wire cylinder-form trellis and it can always be counted on for a bright display in mid-May just as hummingbirds arrive in the area.

'Arnold Red' Honeysuckle

'Hall's' Honeysuckle

Lilac 'Josee' in front of Viburnum 'Nannyberry'

Viburnums: Visitors to Kansas gardens often seem surprised that many Viburnum sp. are among our most stalwart spring shrubs, and it is often perplexing to me to find that many experienced gardeners don’t believe that viburnums, as a group, tolerate full sun well. Take it from me that many species of viburnum tolerate the worst August sun that Kansas weather can throw at them. The viburnum season starts for us with fragrant offerings from Viburnum fragrans ‘Mohawk’ and Viburnum juddii, proceeds through the Viburnum lentago ‘Nannyberry’, and Viburnum opulus ‘Roseum’, and then finishes with the Viburnum dentatum cultivars such as ‘Christom’ and ‘Synnestvedt’, all flowering in their own special times and in their own ways.

  

'Coles Red' Quince

Quince: Chaenomeles japonica, or Quince, cultivars such as the older ‘Texas Scarlet’ and newer varieties such as ‘Coles Red’ bloom in late April in Kansas gardens, and these shrubs are all so well-adapted to our climate as to be almost rampant in their growth habits. I have, in fact, grubbed out several of these shrubs who overgrew their anticipated bounds. Many local landscapes count on these shrubs in late April to shine briefly for a week or so and then to fade into green, undiseased obscurity as the summer and fall move ahead.

Variegated Weigela

Weigela:  I was always jealous of a neighbor who had a beautiful specimen of Weigela florida ‘Red Prince’, which always shone like a spotlight beside his front door, until I realized that just about any gardener can grow Weigela in the Flint Hills. Lately, I’ve been partial to the variegated form (pictured), whose white flowers make a different statement against their pale green and white foliage than ‘Red Prince’ does against its dark green clothes. Occasionally, Weigela will take a little extra water in the heat of the Kansas summer, but it is well worth it to carry a bucket or two at a critical moment if the reward is this early display next spring.



Philadelphia lewsii 'Blizzard'



Mockorange:  Finally, I believe no Kansas or Midwest garden is complete without a specimen or two of Mockorange to perfume the air in May. Philadelphia lewsii ‘Blizzard’ makes a 6 foot tall tower of blinding white flowers every spring in my garden, but visitors have been known to swoon with range of its dangerously strong scent.

'Marie Bugnet'

As an unabashed rosarian at heart, I can’t simply end an article recommending flowering spring shrubs for Kansas without rounding out the spring season by mentioning a few early shrub roses for the area. Without fail, the first rose to bloom in my garden every spring is the Rugosa hybrid ‘Marie Bugnet’, a white, disease-free shrub that reaches about 3 foot in both height and width in my garden. ‘Marie Bugnet’ is followed a week later by the dependable prairie pioneers of ‘Harison’s Yellow’ and ‘Therese Bugnet’, and then the whole rose season ushers me finally into summer. Soon, another growing season moves along, from June promise through August doldrums to November quiet. And I’m left as I am now, in the depths of Winter gloom, waiting for the Spring shrubs to soothe my soul.

'Therese Bugnet' (pink) and 'Harison's Yellow' (yellow)