A midsummer miscellany

Cardoon (Cynara cardunculus), National Museum of Natural History gardens

I don't normally do a lot of walking in mid-summer, but we've had such uncharacteristically pleasant summer weather for the past several weeks that I can't use my usual excuse of heat and humidity to avoid a bit of exercise.  So come with me on a Friday evening as I walk from work in downtown Washington, DC to join my husband for dinner at a restaurant on 14th Street near Logan Circle.  This month marks 23 years since we moved here from a small town in upstate New York, so forgive me if I wax a bit nostalgic along the way!

Lazy summer days

Temperatures cooled down a bit this evening--meaning around 80 degrees (27 C)--so I thought I would do some light garden work after dinner.  There's a reason why this is such an uncharacteristic thing for me to do.  The temperature was deceptive and an hour later I was drenched in sweat, but at least I got some begonias planted (yes, I'm still planting begonias, and still have a few more to go!) and Vitex agnus-castus deadheaded.  The plant was just about finished blooming and trimming it back now will give me a good second bloom in a few weeks.  I'm already seeing a second bloom on my butterfly weed (Asclepias tuberosa), which I deadheaded just two weeks ago.

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.

Why bother?

Trachycarpus wagnerianus after our coldest winter in 20 years

Just as many growers of hardy palms are wondering whether our palms will survive our coldest winter in 20 years, and whether it's even worth growing them, I came across this in the Plant Delights Nursery February 2014 e-newsletter:

Speaking of weather, winter 2013/2014 has been quite an event in many parts of the country, with temperatures finally returning to more "normal" winter levels. We've amusingly watched the last fifteen years as zone creep, aka: zone denial, has taken hold of much of America. It's been fascinating to observe how quickly peoples' memories of hard winters fade when they are only a couple of years removed. Some gardeners have recently admitted being lulled into a false sense of security by the constant media drumroll that our climate has dramatically warmed forever.

Gardeners in Zone 4 or 5 have a few Zone 7 winters where the winter low temperatures don't drop below 0 degrees F, and all of a sudden they decide that Zone 7 plants will actually survive in Zone 4 and 5. It's not uncommon these days to find less than reputable online nurseries listing plants like the hardy banana, Musa basjoo, as hardy to Zone 4 and 5, which is pure insanity. Windmill palms, which we consider marginally hardy for us here in Zone 7b, have now been planted throughout the mid-Atlantic states and even into parts of the Midwest. Because of the recent mild winters, some windmill palms have actually achieved good size before this winter's reality check. My friend Al Hirsch recently reminded folks on one of the hardy palm groups that he had actually freeze-tested windmill palms in the lab, and 5 degrees F was their low temperature tolerance...except for some of the hardier forms. Just because we've had a string of mild winters doesn't mean the winter temperature tolerance of plants change.

Tony Avent is a global warming skeptic, and I disagree with him on that subject (and one cold winter doesn't disprove global warming!).   But I agree with his main point here: many people have been fooled into thinking certain plants are hardier than they really are, because we've had some unusually warm winters for the last decade or more.  I've seen claims that Musa basjoo is hardy to zone 4, and that windmill palms (Trachycarpus fortunei) are perfectly hardy in zone 7, but pretty much anything is "hardy" with a warm enough winter, or if you provide enough protection.

I don't think anybody is suggesting we should stop growing hardy palms or subtropicals, or anything that might be marginally hardy.  I'm certainly not, and I don't think Tony Avent is either, as he makes a lot of money from selling them to us!  But we shouldn't expect (or pretend) plants to be hardier than they really are.  Winters like this one do happen periodically, they will kill (or severely damage) marginally hardy plants, and for those of us in zone 7, windmill palms are among those marginally hardy plants.  

My own attitude has always been that it's fun to grow plants like this and we should do it if we want to!  But we should go into it with realistic expectations, and should expect to either protect or lose our plants when winters like this one come around.  And we need to communicate those limitations and expectations when we advise or encourage people to grow plants like this.

So are all of our windmill palms in the Washington, DC area dead?  I don't think so.  It's still too early to be sure, but I'm willing to bet that at least a few of the local palms, especially those planted in sheltered locations, will pull through.  Many of us are growing palms from reputedly extra-hardy strains, so it will be interesting to see if that makes any difference.  And regarding Al Hirsh's work, he was testing temperatures that are lethal to leaf tissue under laboratory conditions; whether those same temperatures would kill the same palm growing outdoors is another matter, certainly tied directly to the duration of the low temperatures, which affects how deeply cold penetrates into the trunk, where the meristem (growing point) is deeply buried.  Windmill palms are famous for bouncing back after suffering massive damage from winter freezes, so no matter how bad those palms may look this spring, don't give up hope!  Doesn't a view like this make it all worth it?


Garden, early October

Speaking of weather, winter 2013/2014 has been quite an event in many parts of the country, with temperatures finally returning to more "normal" winter levels. We've amusingly watched the last fifteen years as zone creep, aka: zone denial, has taken hold of much of America. It's been fascinating to observe how quickly peoples' memories of hard winters fade when they are only a couple of years removed. Some gardeners have recently admitted being lulled into a false sense of security by the constant media drumroll that our climate has dramatically warmed forever.
Gardeners in Zone 4 or 5 have a few Zone 7 winters where the winter low temperatures don't drop below 0 degrees F, and all of a sudden they decide that Zone 7 plants will actually survive in Zone 4 and 5. It's not uncommon these days to find less than reputable online nurseries listing plants like the hardy banana, Musa basjoo, as hardy to Zone 4 and 5, which is pure insanity. Windmill palms, which we consider marginally hardy for us here in Zone 7b, have now been planted throughout the mid-Atlantic states and even into parts of the Midwest. Because of the recent mild winters, some windmill palms have actually achieved good size before this winter's reality check. My friend Al Hirsch recently reminded folks on one of the hardy palm groups that he had actually freeze-tested windmill palms in the lab, and 5 degrees F was their low temperature tolerance...except for some of the hardier forms. Just because we've had a string of mild winters doesn't mean the winter temperature tolerance of plants change.
- See more at: http://www.plantdelights.com/index/page/static/subpage/Newsletter_2014February#sthash.Y8cauiMu.dpuf

Speaking of weather, winter 2013/2014 has been quite an event in many parts of the country, with temperatures finally returning to more "normal" winter levels. We've amusingly watched the last fifteen years as zone creep, aka: zone denial, has taken hold of much of America. It's been fascinating to observe how quickly peoples' memories of hard winters fade when they are only a couple of years removed. Some gardeners have recently admitted being lulled into a false sense of security by the constant media drumroll that our climate has dramatically warmed forever.
Gardeners in Zone 4 or 5 have a few Zone 7 winters where the winter low temperatures don't drop below 0 degrees F, and all of a sudden they decide that Zone 7 plants will actually survive in Zone 4 and 5. It's not uncommon these days to find less than reputable online nurseries listing plants like the hardy banana, Musa basjoo, as hardy to Zone 4 and 5, which is pure insanity. Windmill palms, which we consider marginally hardy for us here in Zone 7b, have now been planted throughout the mid-Atlantic states and even into parts of the Midwest. Because of the recent mild winters, some windmill palms have actually achieved good size before this winter's reality check. My friend Al Hirsch recently reminded folks on one of the hardy palm groups that he had actually freeze-tested windmill palms in the lab, and 5 degrees F was their low temperature tolerance...except for some of the hardier forms. Just because we've had a string of mild winters doesn't mean the winter temperature tolerance of plants change.
- See more at: http://www.plantdelights.com/index/page/static/subpage/Newsletter_2014February#sthash.Y8cauiMu.dpuf

Speaking of weather, winter 2013/2014 has been quite an event in many parts of the country, with temperatures finally returning to more "normal" winter levels. We've amusingly watched the last fifteen years as zone creep, aka: zone denial, has taken hold of much of America. It's been fascinating to observe how quickly peoples' memories of hard winters fade when they are only a couple of years removed. Some gardeners have recently admitted being lulled into a false sense of security by the constant media drumroll that our climate has dramatically warmed forever.
Gardeners in Zone 4 or 5 have a few Zone 7 winters where the winter low temperatures don't drop below 0 degrees F, and all of a sudden they decide that Zone 7 plants will actually survive in Zone 4 and 5. It's not uncommon these days to find less than reputable online nurseries listing plants like the hardy banana, Musa basjoo, as hardy to Zone 4 and 5, which is pure insanity. Windmill palms, which we consider marginally hardy for us here in Zone 7b, have now been planted throughout the mid-Atlantic states and even into parts of the Midwest. Because of the recent mild winters, some windmill palms have actually achieved good size before this winter's reality check. My friend Al Hirsch recently reminded folks on one of the hardy palm groups that he had actually freeze-tested windmill palms in the lab, and 5 degrees F was their low temperature tolerance...except for some of the hardier forms. Just because we've had a string of mild winters doesn't mean the winter temperature tolerance of plants change.
- See more at: http://www.plantdelights.com/index/page/static/subpage/Newsletter_2014February#sthash.Y8cauiMu.dpuf

Everybody Loves My Big Banana

Pretty much the first thing anybody sees, or remarks upon, in photos of my garden is my banana.  The above photo shows how it looked this morning.  Yes, I have a big banana.

Musa basjoo is commonly known as the "hardy banana" because it is indeed quite hardy, surviving temperatures well below freezing.  In colder climates it acts like a giant perennial, the pseudostems freezing to the ground ever winter and springing back the following summer.  My plant has been in the ground since 2002 and the only protection I have ever given it is a modest pile of mulch, compost, autumn leaves, and/or whatever I happen to cut down in the garden in the fall.

You don't always realize just how fast some plants can grow until you take a few photos over the growing season and compare them.  The next photo shows my garden in early June; pay special attention to that little banana plant just barely visible in the upper left.  Yes, this is that very same banana at the beginning of the growing season:




Now the fun part: here's the same scene in late June just 3 weeks later:




And 3 weeks after that:



If it had stopped there I would have been happy!  The banana is a bit problematic in a small garden as it takes up an awful lot of valuable real estate, and tends to shade out surrounding plants.  Last year I fertilized it only once, in early spring; this year I didn't fertilize it at all, hoping to keep it on the small side.  So much for that!  I often see recommendations to feed bananas heavily but as it turns out, fertilizer isn't nearly as important as establishment, good soil, and adequate water when it comes to growing big bananas.

One final note: the leaves of Musa basjoo are rather thin and shred easily in the wind.  As you can see in the first photo up above, late summer storms can make a mess of the leaves.  So if you plant one, try to site it where it won't be exposed to wind.