Monday, May 18, 2015

What to plant in semi-shade, urban-style

The Harlem terrace has begun to grow. A lot died this winter: three beautiful boxwoods, and every rose. The pots froze, of course, then were buried in feet of snow, and then the tops melted in our overhead noonday sun, and the roots sat in water while the bottom of the pots remained iceblocks, unable to drain. I think they just drowned. 

So my semi shade is not horticulture's semi shade. It is complicated. We have the shadow cast by tall buildings that sandwich each side of our townhouse. It lasts till about noon (at this time of year), when a few hours of intense overhead direct sun begin. Then more shade. Choosing a plant to cope with that kind of stress is not simple; most semi shade plants evolved in woodlands, and like gentle sun, or filtered sunlight. Under high noon they wilt. And I've realized that some full sun lovers can survive here, but others not - in early spring and late fall the sun cannot clear the building to our south. So it's always an experiment. Welcome to 2015.

Japanese forest grass - Hakonechloa macra 'Aurea' (now that the kitty is no longer around it will be able to grow full without having its ends nibbled off - I miss him very much) - a good foil for: Cimicifuga  'Hillside Black Beauty,' a very dark-leafed bugbane cultivar bred in Connecticut and grown by Jim Glover on the North Fork of Long Island. Cimicifuga - now classified as Actaea - is native to the eastern US. I am hoping that it will be happy and reach its 4'- 5' height. And last, very exciting - to me - a foxglove: Digitalis 'Gold Crest.' Reputed not only to re-bloom but to attract hummingbirds. Sold. I have planted three in various spots.

In Brooklyn a week ago I picked up two specimens, from GRDN, the wonderful little garden shop on Hoyt Street, of Corydalis lutea, an exceptionally long-blooming perennial (most flower for between 1-3 weeks, and this Corydalis keeps going till cold weather). It used to grow in the gravel on the floor of our Brooklyn terrace - it does not need a lot of space.

Jim Glover also grows these white Corydalis, and when a friend offered to bring me some plants, I jumped. Yes, please. Corydalis ochroleuca. I think it is gorgeous.

Below - after seeing it in bloom in high forest shade in Central Park, I have wanted to grow swamp milkweed - Asclepias incarnata subs. pulchra. I considered  A. syriaca (common milkweed, which I like to eat), but I think it would need more sun. Maybe some monarch butterflies will find my plant. If you can, grow some milkweeds for the butterflies - their larvae depend on it.

Also spotted at GRDN, this lovely little Heuchera, a cultivar called 'Snow Queen.' I think she's a bit hot. I may have to shuffle pots around again. Heucheras are troopers, and there are dozens to choose from.

The fava beans I have not mown down for salad leaves are in bloom. They handle the light situation very well.

The lilies are up, with annual, self-seeded jewelweed (Impatiens capensis) to keep them company. Along the edges in the wooden planters the herbs are herbing. All the herbs I like - except chives - do well here, which has surprised me. There are also a million volunteering seedlings, from last year. It is fun sorting out the Verbena bonariensis from the quickweed, from the lambs quarters (I am farming the last two in their own pot), from the thyme, from the Nicotiana...

And the empty jar? It is a solar lamp - I bought three in South Africa and we love them.

Light for the nights to come.



  1. All of my herbs died this winter, even the mint which I would have thought was impossible to kill, and even the pots I brought inside, except for the chives which seem to be bouncing back. We lost one rose but the others seem OK. And a very hungry bunny managed to just step over our four foot fence, thanks to the snow, and give our blueberries, fire bushes and forsythias a good hearty pruning. Everything is much bushier, albeit much shorter, as a result. I'm planning some veggies for this year. I think the bunny will like those. ;)

  2. Interesting cultural parameters and a good point about the full midday sun. I'm interested to see how the experiment progresses as I'm sure your results will be useful to other gardeners. Re Actaea v Cimicifuga, I thought it was the other way around, but I'm easily befuddled by name changes. Good luck this season!

    1. Huh - I think you are right, Paul. again :-) I was the one that turned them about. The little blue Roguchi clematis has bounced back, by the way. Amazing. I will post pics when it blooms!

  3. Sorry about all the roses. Lost both of mine - the potted ones - too, but the Knock Out did fine. Am curious about your blueberry. Did it make it thru? are you getting fruit this year? Love the bugbane and the corydalis - may need to look for one or both. Am trying to add color with leaf variation this year.

    Looks like a good place for an afternoon cocktail.

    1. Glad your Knock Out made it! The blueberries came back, webb, but they don't look very well. The oldest, Brooklyn one, has fewer flowers than last year (but that was a bumper year) and the two taller ones that I pruned hard after fruiting last year look rather...unsure of themselves. I am doing the proverbial wait and see. Heucheras also add lots of colour in leaves...

  4. I brought my deck container roses inside in December and had them overwinter on the unheated back stairs - I doubt they would have made it through this record-breaking winter outside. The Asclepias incarnate will hopefully do well. In my parents' Michigan garden it flourishes in all sorts of places, from fairly dry spots that bake in the sun all day to a shady swampy spot that only gets a moment of direct sun in the early morning and evening.

    1. That was clever of you. I need unheated back stairs. Next time, if there is a next time, I think I might cover the pots in plastic. It will look awful but it will stop the whole snow melt thing.

      I am glad I lifted the lilies or they would have been (soggy) toast, too. Good to know about the Asclepias in your parents' garden...

  5. Have you considered tropicals? I had a crossandra that loved my patio: shade or blazing hot sun. It did better than anything else in the container barrel.

    1. Yes, indeed - the beans and cardinal vine on the birch pole screen are tropicals and are back as annuals because they did very well last year.

  6. solar lamp? empty jar filled with fireflies?
    Gods Peace
    Ann-sofie Kassberg

  7. That does make for a challenging setting for plant growing. Not having the winters that are common in NYC I have no idea what would winter over although I suspect you're right and the plants drown rather than freezing. Even though we don't get a great a lot of severe winter weather when we've had a winter where the plants have frozen, thawed, frozen again we've always lost some plants, oddly some of the oldest ones which one would think would be the hardiest. Gardening always brings new opportunities :-)

  8. Leslie in OregonMay 19, 2015 at 1:56 AM

    I'm sorry about the plants you lost last winter. In the western valleys of the Pacific Northwest, we had the opposite weather patterns last winter: mild temperatures and low precipitation. Our time will come...

    Thank you for the plant ideas. Our north deck's light exposure is quite similar to yours during our dry summers (instead of buildings, Douglas fir, maples and hills surround this deck), and we have spent 29 summers experimenting with growing flowers and vegetables on it. At this point, since I usually work from home, I protect the shade-loving plants by raising the big sun umbrella over them during the daily period of intense sunlight.

    The wood floor of our deck looks very much like yours. We have learned to keep our terra cotta pots and wood boxes on low, flat, wheeled dollies so that their damp undersides do not cause the deck floorboards to rot. (And the wheels allow us to move them easily, for optimal amounts of sun, in the spring and fall) How did you keep the clay pots in which your plants overwintered from cracking this winter?

    Best regards, Leslie

  9. Marie I was wondering if you could share the name and make of your composter - are you happy with it? - I have not been able to locate the post that contained the information.
    Thanks as always for your lovely blog, I refer to it all the time since more and more of my vegetables and herbs are being grown in pots.

    1. Ingefaer, here is the post:

      Jora JK 125. But I am writing a post about the composter. It no longer resides here!!!

      The fault is mine, really, not the composter's, so I would not discourage you. Post to come.

    2. Thanks Marie - I will wait for your post.

  10. All these botanical names are a horticulturist's Handel. Musical!
    Our boxwoods here in the Netherlands also took a battering this winter: rain, sleet, snow and finally ice that lay heavily on top for a week or so. Many branches in the hedges snapped off, leaving holes that will probably never fill out.
    Winter sucks! (But luckily, there is your blog to look forward to!)

  11. I really loved this post, for I have the trouble, on my balcony, of having (only) the afternoon sun, for about 5 hours, and it shines down with such hardness as if there was no tomorow. My tomatoes are happy, as much as other things that love full sun (they have to wait till it's 1pm), but not that much my amaryllis.
    I did wanted to ask, if it was possible for you, to maybe make a post about roses on balcony. I know that you have written about them quite often, but there doesn't seem to be one full entry. They have been such a vital part of your high-up gardening, and I would just love to read one general article on them. And yes, I am awaiting a delivery of my (very first) rose and I am very curious of the right from-the-beginning-treatment for them.


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