Testing the limits: 2015 winners

If you're going to "test the limits" you have to be willing to take a few losses.  That was the point of my previous blog post (see Testing the limits... and finding them: 2014-2015 losers) when I wrote about the plants I lost last winter, which along with 2013-2014 brought my area's two coldest winters in 20 years.  Each of those two winters, on its own, wasn't so unusual; we get winters like that every 10-15 years and we were several years overdue.  What was unusual was getting two such winters back to back.  That makes the survivors all the more special to me.  They don't necessarily look their best this year, but considering the minimal protection I gave them I'm more than happy.

Testing the limits... and finding them: 2014-2015 losers

August 2015: no more windmill palms

I've always been interested in testing the limits of marginally hardy plants, plants that are new to cultivation, and plants whose hardiness is otherwise unknown.  For better or for worse, my last two winters have been very good ones for testing hardiness!  The low temperature in my back yard in Washington, DC (zone 7a) during both winters was about 5 degrees (-15° C), my area's coldest temperatures in 20 years.  Despite the similar low temperatures, the two winters were very different in terms of wind, snow cover, and timing and duration of the cold.  Several plants that survived the first of the two winters didn't make it through the second; in some cases I think they were weakened going into the second winter, but I also think the ground froze more deeply, doing more damage to otherwise healthy plants.

Summer means great gardens in Washington, DC

National Museum of Natural History (Constitution Avenue entrance)

I'm privileged to work at the Smithsonian's National Museum of Natural History in Washington, DC and a beautiful garden greets me as I arrive at work every morning.  As the summer gets hotter and hotter, it just keeps getting better and better.  I know a lot of people don't like the heat and humidity of a Washington, DC summer but this is when our public gardens really start to hit their stride.  Don't get me wrong, I love spring gardens with their tulips, daffodils, peonies, bleeding heart, foxglove, poppies, and bluebells, but by mid-summer, most of these plants look the worse for wear.  Some of them, like oriental poppies, bleeding heart, and most spring bulbs, have the good sense to go dormant in our summer heat but gardens that depend too heavily on these spring-flowering plants aren't worth seeing the rest of the year.

Winter, winter, go away

Winter in the city

I promised a blog post about my recent vacation in Ft. Lauderdale, but the weather has intervened.  An unusually late snowstorm that produced a record amount of snow for this date (ca. 5 inches) shut down the federal government on Thursday and generally pissed off everybody in the Midatlantic region.

Needle palms: big, bigger, biggest

Needle palm, January 2015

Something smells a bit funky in my garden this time of year.  The fruits of needle palms (Rhapidophyllum hystrix) ripen in late fall in dense clusters at the base of the plant and look--and smell--like some wild animal came along and pooped out a big pile of scat.  I suppose this must be attractive to some animal that disperses the seeds, but I don't think anybody has figured out for sure what animal that might be.  The flowers it produces in late spring are about as appealing, looking like some strange fungus attacking the plant.

Throwback Thursday: January 2014

Sunset, January 2014

This is how I'd like to remember January a year ago: a month of breathtaking winter sunsets.  Instead, it was a month of breathtaking cold: a disaster for my garden, and for anybody growing hardy palms or any other marginally hardy plants.  Meteorologists had been making dire forecasts for several days, prompting me to ask in early January "Is this the apocalypse?"  I wrote then, "The weather forecasters are starting to talk in apocalyptic terms, telling us that this event is likely to give us our lowest temperatures in 20 or maybe even 30 years."  Two days later, when I posted "It was @!#$% cold last night!", we had recorded DC's coldest temperatures since 1994.


Trachycarpus wagnerianus at 5° F (-15° C), January 7, 2014

The low that morning in my own back yard was about 5° F (-15° C).  My Trachycarpus wagnerianus, which I had grown from seed in 2001 and had been in the ground since 2003, was the first casualty.  The damage was immediate and irreversible, with the leaves appearing freeze-dried and never recovering.  My other two windmill palms looked almost as bad, but when the weather went above freezing again, they sprang back and showed little damage.   I think they would have made it, and maybe the waggie too, if we hadn't gotten several more visits from the "polar vortex" later that month.  Although the subsequent lows were several degrees warmer, some of them were more extended and the cumulative damage proved too much for two of my palms.  I wasn't surprised to lose my waggie but my T. fortunei "Nainital" was a more surprising casualty.  Even the sole surviving windmill palm, T. fortunei "Bulgarian", lost all its foliage--even the ones with a bit of green left in them ended up dying completely--but began to push out new leaves come April, and in May it even bloomed.


Trachycarpus fortunei "Bulgarian", March 2014

Since then it has recovered a bit, but not nearly as much as I'd like going into another cold winter.  Normally, I wouldn't be worried about windmill palms until lows drop below 10° (-12° C) but in its weakened state, I fear that it won't take temperatures nearly as cold as last winter's to kill it.  But I'm as determined as I was last year to forgo any protection, to see just how hardy this plant really is. 


Trachycarpus fortunei "Bulgarian", early January 2015

Last winter killed about half of the windmill palms in the Washington, DC area.   2015 got off to a mild enough start, with a high of 65° (18° C) just 3 days ago.  I was hoping this hinted at a warm winter but no such luck.  A year later, almost to the day, we're having a near-rerun of January 2014: the low temperature last night was 12° (-11° C).  That was at the upper range of the range that was forecast, so not as bad as it could have been, but I'm just not ready for temperatures like that again.  What will the rest of this winter bring?  I don't even want to think about it; better to dream about the warm weather, just a few weeks away.


Edgeworthia chrysantha, dreaming of spring

I'll end as I began, with a January sunset, this one from just a few days ago.


Sunset, January 2015

A year of blogging

Garden one year ago

Today marks one year since I started this blog and published my first post.  The most immediate reason for blogging was the shutdown of the federal government last year: being stuck at home for an indefinite period of time, I decided to use my time productively rather than watch TV and surf the web!  I had been thinking about blogging for a while, and in fact had tried my hand at blogging once before (I was particularly proud of Transitional Species in Insect Evolution, about the evolution of termites from social, wood-eating cockroaches); but before I get too self-congratulatory I should also note that my previous attempt at blogging lasted just over a year!  Finally, after years of posting commentary and photos on several plant and gardening-related websites and discussion lists, I realized that in a very real sense I was already blogging; I might as well pull it all together on one site, attached to my own name.  Plants and gardening have always been a passion for me, and I hoped to direct and focus that passion.

Washington windmill palm winners (and losers)

Scottish Rite Temple, October 2012

In early February, when we were in the middle of our coldest winter in a very long time, I wrote a blog post rounding up several windmill palms (Trachycarpus fortunei) that I've encountered in the city.  Most of these palms were several years old and had suffered little damage from our recent mild winters but as I wrote in February, "...our coldest winter in 20 years will surely put these palms to the test.  A general rule of thumb is that single digit temperatures are likely to cause damage, and temperatures below zero will cause massive damage and in many cases kill the palm outright (although duration of the cold is also critical).  This makes windmill palms marginal in zone 7: sooner or later, they will experience temperatures capable of killing them."

What's missing from this picture? (Hint: palms)

Garden, late August 2014

What's missing from this picture?  Those of you who have been following my blog since last year (or who read the post title) probably have a good idea.  But this photo from the same time last year really brings it home:

Southeastern Palm Society summer meeting

Southeastern Palm Society members

Members of the Southeastern Palm Society were treated to a meeting last weekend at Plant Delights Nursery and Juniper Level Botanic Gardens in Raleigh, North Carolina.  It had been several years since my last SPS meeting, and I'm always looking for any excuse to visit Plant Delights, so I decided to drive from Washington, DC to Raleigh to attend the meeting.  (I was fortunate to make it in 5 1/2 hours this trip.  I've made the trip in 4 1/2 hours, but once it took almost 8 hours.  The less said about I-95 through northern Virginia, the better.)

Smithsonian Gardens, part 1: National Museum of Natural History

Monarda fistulosa, Butterfly Habitat Garden

[This is the first in a series of posts about Smithsonian Gardens.  Please see my introductory post here.]

The National Museum of Natural History is one of the Smithsonian Institution's largest and most popular museums, vying with the National Air and Space Museum as the most-visited Smithsonian museum.  But many visitors overlook the gardens around the building, including the Butterfly Habitat Garden and Urban Bird Habitat Garden.  These gardens deserve more attention; not only are they beautiful, but they are AAM (American Alliance of Museums) accredited and have been designated as wildlife sanctuaries by the National Audubon Society.

Recovery

This has been a bit of an odd spring for me and my garden.  After my area's coldest winter in 20 years, here it is the last day of May and I'm still waiting to see what survived and what didn't.  Many plants that I thought for certain were dead and gone are finally showing signs of life, so in the meantime I'm trying not to disturb plants that may or may not be alive.  For example, just a few days ago I decided to transplant something, and accidentally uncovered a begonia that was sending up a strong new shoot from deep underground.   Just this morning I discovered hardy elephant ear Colocasia 'Pink China' finally coming up, and two new shoots on my hardy banana (Musa basjoo).

So I'm holding off a bit on planting new plants, although it's killing me not to fill the gaps left in my garden by dead or badly damaged plants.  (You can see in the photo above my recovering windmill palm at lower left, and a seemingly dead fig at upper right).   I've also lost much of my shade, so I'm not certain where to plant the gazillion potted begonias from my breeding program that need to get into the ground soon.  My window to get everything planted, before summer heat, humidity, and mosquitoes make gardening unbearable, is rapidly closing.  At what point should I declare plants dead and plant new ones in their place?

It will be quite a while before my garden is anywhere near back to normal, and it will look nothing like last year's garden.  That's the nature of this hobby; every year is different, and our creations grow and change, sometimes in the ways we planned but often in ways we never expected. 

Spring has sprung

Iris 'Buckwheat'

What a relief that spring is finally here!  In fact the last 3 days have felt more like summer, humid and with highs close to 80.  In addition to the spring perennials cheering me up, I'm seeing recovery on several plants that were badly damaged by the winter and that I thought (or feared) were dead.  To recap, this was the Washington, DC area's coldest winter in 20 years, and was a good test of all the marginally hardy plants we're growing here!  The low in my own yard was about 5 degrees in early January, with several more lows in the 9-12 degree range and several periods of temperatures well below freezing.

Survival of the fittest?

   
Garden, early December (left), mid-April (right) (click on photos to see larger version)

This side-by-side comparison shows very graphically how bad a hit my garden, and especially my palms, took after this winter.  The photo on the left was taken in early December, after a hard freeze had knocked down the hardy banana (Musa basjoo) but before the series of cold waves we had in January.  The photo on the right was taken just today; daffodils may be blooming merrily but not much else is looking good!  Note the windmill palms: Trachycarpus fortunei "Bulgarian" in the lower left, T. fortunei "Nainital" at upper right, and T. wagnerianus immediately to its left.

Bulgarian wins!

I've been trying to put together a blog post with some photos I took over a week ago, but right now I have to share this photo that I took just a couple of hours ago.  A few weeks ago I asked the question, Is my palm dead?  For at least one of my palms, the answer is no!

Will summer ever come?

This has been the winter that just won't let go.  Just two days after a lovely springlike day that saw crocuses blooming, we got whomped with another snowstorm.  The forecast as of last night was 3 to 6 inches of snow for the region, and 1-3 inches of snow in the city.  Hoo-boy were they wrong!  I measured 8 inches of snow on my back deck this morning.  The above photo shows the view from the deck this morning.  Meanwhile here is the deck itself:



After a winter like this one, it's hard to remember that summer will eventually come, and the weather will be warm again!  In fact before you know it, we'll all be complaining about the heat and humidity.  In just a few months this will be the view from my back deck (perhaps minus a few of the palms!):



And this will be the deck:



In the meantime, all I can do is dream, and keep reminding myself that spring is right around the corner!

Is my palm dead?

Garden, mid-March after our coldest winter in 20 years

Is my palm dead?  Lots of people are going to be asking that question over the next few weeks because frankly, the palms look dead.  The short answer: maybe, maybe not.  Hardy palm legend (and mystery author) Tamar Myers supposedly once said, "don't declare a palm dead until spring, and don't declare one alive until summer."

Waggie vs. Nainital

Trachycarpus wagnerianus (left), T. fortunei "Nainital" (right)

Not all windmill palms are created equal.  In fact there seems to be quite a bit of variation in cold hardiness among them, with some selections or strains reputed to be hardier than others.  The above photo illustrates very clearly such a difference.  Many sources claim that "waggies"--Trachycarpus wagnerianus, which is probably no more than a dwarf version of T. fortunei that arose in cultivation--are among the hardier windmill palms.  In fact, that's why I ordered seeds of this species 13 years ago, when I was just starting to get into hardy palms.  But after this winter, I'm not so sure about that.

The windmills of Washington

For the last two decades, some of the more adventurous gardeners in the Washington, DC area have been planting Trachycarpus fortunei, commonly known as "windmill palm".  Although the dwarf palmetto (Sabal minor) and needle palm (Rhapidophyllum hystrix) are considerably hardier, the windmill palm is the hardiest of the palms that grow trunks and can properly be called "palm trees".  Exactly how hardy is still a matter of debate, and our coldest winter in 20 years will surely put these palms to the test.  A general rule of thumb is that single digit temperatures are likely to cause damage, and temperatures below zero will cause massive damage and in many cases kill the palm outright (although duration of the cold is also critical).  This makes windmill palms marginal in zone 7: sooner or later, they will experience temperatures capable of killing them.

Duration, duration, duration

Garden at the end of January

When I give talks about growing hardy palms or other marginally hardy plants, one of my talking points is "location, location, location".  My point is that I live in a city, so I benefit from an urban heat island that keeps me quite a bit warmer than the surrounding suburbs.  In addition, there are microclimates within the city, and even within our own yards, that can add or subtract up to a half zone of hardiness.  For example, my property is on a north-facing slope that receives no direct sun from mid-November to mid-January; overnight low temperatures in my yard are nearly always several degrees colder than the "official" temperatures for Washington, DC as recorded at Washington National Airport (which, ironically, is not even in DC!).  This morning the official low at DCA was 16 degrees, but at 4:00 am the temperature in my yard was 12 degrees.