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rosaprimula

Centaureas

Campanula UK Z8
11 years ago

Some plants have never made it onto my radar despite their total suitability for my garden. Centaureas, for example. For me, the cornflower or Knapweed has either been a lovely, but desperately tall annual (I am never going to stake an annual!), or a dull and very weedy knapweed. Finally, some bored browsing where I came across a national collection and the scales have fallen from my eyes. Fortune intervened the very next day when a friend of mine offered me a C.pulcherrimma, now sitting in my gravel garden in all its lilac loveliness. This part of the allotment is finally getting a sorting out so all the remaining duffers (hemerocallis,) or maniacs (those eryngiums and acanthus) are being rehomed or composted. I predict a looming craze. As a novice to knapweeds, do tell all.

Comments (13)

  • wieslaw59
    11 years ago

    I have/had many different Centaureas. I'm warning against: C.cheiranthifolia(very running), C.salonitana(very very running, very very beautiful), C.montana Jordy(and all the others in the same colour- totally invisible flowers, blending in with the surroundings).

  • denninmi
    11 years ago

    I haven't grown this one yet, but I'm coveting it -- when I find one for sale locally I'll pick one up.

    Here is a link that might be useful: C. montana 'Black Sprite'

  • wieslaw59
    11 years ago

    Dennimmi, this is exactly what I'm warning against. You will regret it. The flowers are already invisible at a distance of 1 m.

    {{gwi:240080}}
    {{gwi:240081}}

  • donna_in_sask
    11 years ago

    The perennial bachelor's button, Centaurea montana is invasive. The foliage is coarse and the flowers are sparse, not worth growing, imo. There needs to be vast improvements in plant breeding before I'll grow them again.

  • linlily
    11 years ago

    I'm not a fan of Centaurea montana either. I had a friend send me some of her white one - Centaurea montana alba. I grew it for a few years and it completely took over the area where it was planted. It ran and ran and ran. I pulled it out, only to have it return the next year in the same place, blooming mixed blue and white flowers on different parts of the plant. My neighbors want it, and they are welcome to it.

    I had a seedling come up last year on the other side of the house from the above plant. I did not pull it out last fall and it set buds and began to bloom this spring. It was a beautiful shade of dark lavender. I was so pleased with it, and thought of keeping it until it became covered in powdery mildew. My neighbors also want this plant, and I'm glad to give it to them.

    My experience with the blue variety is that it runs and also self seeds liberally. My daughter had a couple Mountain Bluet plants put in to her front landscape when she had the whole front of her house redone by a landscaper. There was Mountain Bluet everywhere, in a couple of years. It even came up between the seams of her cement sidewalk. I agree with Donna. Centaurea needs some improvement in plant breeding so that it's garden friendly.

    Linda

  • a2zmom_Z6_NJ
    11 years ago

    I have to disagree about Centaurea montana. As with many plants, it all depends on where you're growing it. I've had it in my garden for years and the most seedlings I've ever gotten were three, most years I have none. And for me, it's a very heavy and beautiful bloomer. My only real problem is that it's a favorite of the local bunny population.

    Here's a picture of a bloom intermingled with a delphinium:
    {{gwi:237514}}

    and here's a picture of it along with a bunch of other plants:
    {{gwi:240082}}

  • donna_in_sask
    11 years ago

    I think if you have the room and you want it in your garden, then go for it. I dug the main plant out ten years ago and I am still having pieces appear in my flower bed every year, and I don't even let it flower...gives you some idea of its tenacity.

  • mytime
    11 years ago

    I found C. montana easy to keep in check the first couple of years. And then WHAM...like several others have said, for me it suddenly started growing everywhere, including cracks in the concrete.

  • Campanula UK Z8
    Original Author
    11 years ago

    mmmm, C.montana is a bit of a beast but I am definately seeing C.dealbata and C. Blewit in my garden. Thanks for the heads-up, Wieslaw - am making more of an effort to avoid running plants as I am heartily sick of digging up huge clumps of thuggery. Only yesterday, I was on my second massive wodge of ditchlilies this week (not mine) and yanking out heaps of daylily roots involved a mattock and landscapers bar and an early bedtime with an icecream reward - might be a clue there as to why I am finding the huffing and puffing of a jobbing gardener increasingly hard work!

  • echinaceamaniac
    11 years ago

    These won't grow here. I think it's too hot. Not sure though.

  • ripley529
    10 years ago

    I have the blue color I planted last spring. It was beautiful this year. Loved it. I only noticed 2 offspring from last year's bloom. Mine is planted in partial shade and is thriving there.

    If you dead head these, will they rebloom?

  • rouge21_gw (CDN Z5b/6a)
    10 years ago

    I find that rabbits love my centaurea..especially when they first arise in the spring.

  • charlie-ia
    9 years ago

    does anyone know "amethyst in snow" ? It has white flowers with blue/purple centers. Do the petals fade to lilac, or is this a different variety? Seems vigorous. I have it in a pot at the moment.
    If your centaurea gets mildew cut it right back and feed it. It will bounce right back