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Johnson’s blue geranium

Good afternoon everyone.  This time last week one of my Johnson’s Blue geranium was an absolute picture.  Not so now 😒 Anyone have any idea what’s having a munch? Thanks in advance. 


  • Jason-3Jason-3 Posts: 391
    It's will be caterpillar or slug, or a combination of both. Just as a heads up if you haven't grown it before. It spreads intrusively via ryziomes. Around 10 meters in my instance, the growth is patchy and stragley
    I've been trying to get rid of it the past 2 years. I dug around a bin bag full of roots last month.. 
  • K67K67 Posts: 2,507
    I found tiny green caterpillars on a geranium that looked like yours.
  • pr1mr0sepr1mr0se Posts: 1,193
    It can be beset by tiny green caterpillars as stated by K67.  On the other hand, the flowers really are an intense blue, and in the past, I have ignored the leaf degradation and concentrated on the flowers.
    It can spread - and it doesn't repeat flower, so you may want to rethink whether or not it is worth keeping.
    In my previous garden, I was quite forgiving for the flush of flowers each year.
  • AllyblueeyesAllyblueeyes Posts: 409
    @Jason-3 @K67  @Shrinking Violet   Thanks everyone.  I love hardy geraniums and Johnson’s Blue was my first love (many years ago) however, over the years they have become very straggly and I’ve been a bit disappointed.  The bees love them so I’m reluctant to get rid.  I’m growing Rosemoor this year which is a bit more robust, leaf-wise and the flowers are beautiful but they only flower once?  Any tips for hardy geranium that look after themselves and repeat flower?  Don’t mind what colour as long as the bees love them 🐝   Thank you 😊 
  • Dirty HarryDirty Harry Posts: 1,048
    I'm new to it but Rozanne is about to come into flower shortly and will remain that way for months.

    I have Johnson's blue in bloom just now and it's fantastic, didn't realise it could spread quite so much. Makes a mockery of the 30cm x 60cm dimensions that get listed for it.
  • Lizzie27Lizzie27 Posts: 11,676
    I have Johnsons Blue as well but can't get rid of it. A lovely blue as you say but too rampant for my liking.
    North East Somerset - Clay soil over limestone
  • AllyblueeyesAllyblueeyes Posts: 409
    @Dirty Harry @Lizzie27 Thank you.  I’ve grown Rozanne but it’s never been successful in my garden 😕 I know it’s supposed to be easy!  The Johnson’s Blue was gorgeous a week or so ago but yep .... too rampant, holey and leggy now.  I’ll try cutting the JB back and see what happens 🤞
  • FireFire Posts: 17,398
    Can I ask how long Johnson's Blue lasts - is it similar to Rozanne? Also, how does the colour compare?
  • LG_LG_ Posts: 4,255
    It's interesting how the same plant behaves so differently in different places! I had Johnson's Blue. Lovely colour for a short time but never really thrived, looked leggy and certainly didn't spread. Eventually it just died off. I replaced with Rozanne, which flowers on and on. Still quite leggy, but that's OK in the spot where I have it. It really doesn't like drought, which we have a lot of, but as long as I remember to water it it's fine.
    'If you have a garden and a library, you have everything you need.'
    - Cicero
  • AllyblueeyesAllyblueeyes Posts: 409
    Didn’t Rozanne get RHS plant of the year a few years back?
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