Pruning Big-Leaf Hydrangea to control size

Discussion in 'Woody Plants' started by dt-van, Sep 7, 2006.

  1. dt-van

    dt-van Active Member 10 Years

    Messages:
    300
    Likes Received:
    10
    Location:
    Vancouver, Canada
    I have a pink mop-head hydrangea which was received as a potted gift plant about 8 years ago. Our townhouse yard is small and I need to keep it as compact as possible without losing all blooms. I prune it every year but never seem to get the amount and timing right, so it's either a good size (2.5-3'), with no flowers at all or too big (>4) with flowers on about 1/3 of the stems. I'm in Vancouver BC; when should I prune and how much? Do I prune flowering stems and leaf-only stems differently? Do I prune high now to allow for winter damage to branch tips, and prune lightly again in early spring?
     
  2. Rima

    Rima Active Member

    Messages:
    991
    Likes Received:
    0
    Location:
    Eastern Canada
    If you were to prune it (in Nov. or March) right back quite radically, while you might lose flowers for this year, the new growth would likely come in smaller (as it would in a bonsai), so it would give you a better start for years to come, though you might still have to prune hard again in future.
     
  3. smivies

    smivies Active Member

    Messages:
    793
    Likes Received:
    0
    Location:
    Kingston, Ontario, Canada
    Your H. macrophylla will only flower on previous year & older wood so the goal is to retain as many buds on the stems as possible for next spring. Prune once a year after the flowers fade (~early summer) to slightly smaller than the size you want (it will grow into your desired size). Remove weak stems at that time as well.

    My experience with Hydrangeas is that after a really hard pruning (especially when dormant), the growth will be vigorous & tall with even larger leaves than is normal for the plant. In fact, that's my experience with virtually every woody broadleaf plant.

    The technique for reducing foliage size in bonsai is called leaf pruning (defoliation) and involves removing 60-90% of the leaves from existing stems. The new leaves grow from the existing axials and are generally smaller in size.

    Simon
     
  4. Rima

    Rima Active Member

    Messages:
    991
    Likes Received:
    0
    Location:
    Eastern Canada
    Hi, I wasn't referring to the foliage necessarily shrinking, but the new branches... I defoliate my trees all the time for smaller leaves (though only maples get it all at once :-).
     

Share This Page