Sunday, June 4, 2017

The Temptation of Two Spring Anemones

This spring, two perennials that may tempt you at nurseries are Anemone canadensis and its kin Anemone sylvestris. Both have really pretty white flowers that may stop you in your tracks, but be cautious, both are very aggressive plants. If you're aware of this and can choose a location where their spread can be curtailed, adding them to your shopping cart won't be something you come to regret.

As you probably know, I usually shy away from aggressive plants. I've had too many problems with them in the past. Groundcovers, like Anemone canadensis, do have their uses such as under a large tree. That's exactly where I have this spring perennial. 

In early June, the small area under our black walnut tree is a sea of little white flowers. It has colonized the entire area crowding out my hostas. I ended up having to transplant the hostas to another part of the garden. Thankfully a rocky lip generally keeps Anemone canadensis's spread in check on all sides. Even so, it occasionally pops up in the adjacent pathway, where I have to pull it out.

Anemone canadensis makes a great understory for spring bulbs. Late flowering tulips, daffodils and alliums look even nicer with a carpet of white at their feet.

Anemone canadensis is a North American native that can be found growing in dense colonies on river margins and in moist meadows. This is a plant that's adaptive to a range of conditions and can easily be grown in average, well-drained soil. In my garden, it gets morning sun and afternoon shade.

Meadow Anemone or Windflower, Anemone canadensis has upward facing white flowers on erect hairy stems. The plant has a mounded shape and deeply-cut, shiny green leaves. Again, this is not a perennial for a mixed flowerbed. This plant spreads by creeping rhizomes and is best left to naturalize in a controlled area. Height: 30-60 cm (12-23 inches), Spread: 30-60 cm (12-23 inches). USDA zones: 3-8.

Anemone sylvestris

Anemone sylvestris is native to Europe and Asia. The flowers are a little larger than those of Anemone canadensis and stand higher above the plant. Anemone sylvestris and Anemone canadensis have a similar mounded shape, but the foliage of Anemone sylvestris is a lighter, matt-green.

Again, Anemone sylvestris is a spreader that can quickly dominate an area.  The best place to use a plant like this is in a garden bed with a clearly defined edge that can control its spread. 

Snowdrop Anemone, Anemone sylvestris blooms just ahead of Anemone canadensis. The nodding white flowers are held high above the plant on wiry, green stems tinged by red. Anemone sylvestis has matt-green leaves and a mounded, bushy shape. Like Anemone canadensis, this perennial will spread and colonize an area. The flowers are followed by fluffy seed heads. Divide in fall. Full sun or part shade. Height: 30-45 cm (12-18 inches), Spread: 30-60 cm (12-23 inches). USDA zones: 2-9.

Here and in the two of images above is Anemone sylvestris
Private garden in Mississauga, ON.

My experience of this second anemone is rather brief. Anemone sylvestris has been on hold in my nursery bed while I decide where I'd be brave enough to plant it. 

On a recent garden tour, I had an opportunity to ask another gardener about her experience with its aggressive nature. She found it did spread, but was not the worst behaved plant in her garden.

As you can see, the flowers are quite beautiful. What do you think? Dare you invite either of the spring anemones home with you?


  1. Anemone canadensis is super invasive in my garden! I have a. sylvestris controlled but not the other. It's a beautiful thug.

    1. Thanks for weighing in on Anemone canadensis Tammy!

  2. I have a lot of A. canadensis, but the rhizomes travel very close to the surface of the soil. My yard is sandy loam so it's easy to fork/hoe it over every couple of years and rake out the rhizomes.

    1. Thanks for sharing this Cricket. I have found that it is fairly easy to remove it where unwanted too.

  3. Last year I planted about 20 a. Japonicus. Are these the same thing? As far as I can tell maybe one or two survived but won't know for sure until/unless they bloom. I'm zone 6a/b and clay soil so I'm a little worried. I wanted them to understory my limelight hydrangeas. I'd be willing to try the Sylvester or canadensis if I'm in the right zone or even close. I think they are beautiful also planted 60 blue ones, none of which came up this year or last so maybe I'm doing something wrong. Also what are the tiny blue flowers planted in with thesvestris pics? Thanks for any advice or help.

    1. Japanese Anemones are not the same exact thing. Japanese Anemones bloom in the fall. They are also slow to appear in the spring, so you may not have lost as many plants as you think. My experience with them is more limited, so I did a bit of research.

      Fine Gardening magazine offers this background:
      Anemone hupehensis var. japonica, the semi-double form of A. hupehensis, was exported to Japan, where it was cultivated for centuries and escaped into the wild. Its cultivars offer semi-double, somewhat smaller blossoms. After he found a semi-double form in a Shanghai graveyard in 1843, Robert Fortune sent it home to England, and Europeans immediately began breeding new garden forms.
      Anemone × hybrida plants are commonly referred to as the Japanese hybrids. They’re the result of a cross between A. hupehensis var. japonica and A. vitifolia, a tender Himalayan species with grapeleaflike foliage and white flowers. There are a great number of cultivars available today, varying in flower form, color, and height. Anemone tomentosa is native to the higher altitudes of northern China. It’s undoubtedly the hardiest and most vigorous of the fall-flowering anemones.
      Read more:

      As to their invasive nature, one source said:
      "Japanese anemones can colonize large areas and become almost thuggish, rapidly reappearing if you try to eradicate them. But, despite their robust and long-lived qualities, they can also be difficult to establish because they dislike disturbance. When buying, go for well-grown, larger specimens and plant them in rich friable soil in semi-shade. If conditions are not ideal, they creep towards cooler soil, then romp away."

      Another source said:
      "Japanese anemone (Anemone x hybrida) is an attractive plant, loved by many. It is a hybrid of three Chinese anemone species that has white, pink or lavender blooms in late summer.
      It is also hated by some when they decide to remove it. I don't know just where it would fall on a chart of persistence, but it would have to be at the higher end. It forms clumps with a mass of rather thin, dark brown, fibrous roots. Buds that grow into new plants can form on the roots, particularly on ones that are a bit thicker. It also sends out horizontal roots that can grow new plants at a distance from old clumps, and it may regrow from cut roots. So the short answer is that the way to get rid of the plants is to remove all of their roots. If a plant comes up, you know you missed some root that was thick enough to bud.
      Compared with mint, the roots of Japanese anemone will be thinner, making them easier to miss. You may eventually decide, at a time of year when other plants in the bed are least active, to remove them temporarily while you search for Japanese anemone roots."

      One thing that makes me question using them as an understory for limelight hydrangeas is their height. These are pretty tall plants for an understory. The mature height is 2-4 feet.

      I am sorry that none of this may make you feel reassured about the understory you are trying to create. Myself, I think I would tend to shy away from anemones as an understory and go with something less problematic. The tiny blue flowers are forget-me-nots, by the way.

      Finally here is a link to an article by the Chicago Botanical Garden on Japanese Anemones with more information than you may ever need to know:

  4. Elles sont belles ces anémones blanches ! Ici au jardin, il y en a des roses doubles !

  5. I discovered this growing wild in my area in the kawarthas in mid May. Mine is also pink and blue as well as white. The leaves are heart shaped. It doesn't seem to be either of the two species you described here. Very pretty plant and the foliage is nice too once the blossoms die.

    1. Sound like you have discovered another of the native anemones. For instance, there is Rue anemone or Wood Anemone, Anemonella thalictroides but this doesn't sound quite like the one you describe.

  6. I think it may be anemone americana. I was going to use it in the edge of the garden but now wonder how invasive it is.

    1. Thanks for adding the link. I think you might be right Susan (although I'd only loosely describe the leaves as "heart-shaped"). I went further and looked up more information on anemone americana and found that Cornell University suggests it is not invasive. Here's the link:

  7. They are so pretty and tempting. A. canadensis was handed to me by a lovely woman at a garden show. It was free. That should have been the tip off. It tries to strangle my roses, peonies, clematis and any other perennial it can find. I pull armloads out every year. I rue the day I took that little pot from the innocent looking garden lady and said 'thank you'. No wonder she smiled. She knew.

  8. I had no problem with A. sylvestris in my last garden but it was planted in dry shade. After reading this, I'm going to move the two new plants I just bought from one of my perennial borders to my dry shade mailbox garden out by the road.

  9. spring garden is heavenly, just loved it!!! Ahhhh....bless Buddy, 18? gosh, what a grand age. Lovely seeing Jasper and Scraps too. Gorgeous, all three of

  10. Uh oh!
    I bought and planted 3 of these this year.
    They are so pretty though. :-)


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