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I suppose it's vine weevil on my bergenia

berardeberarde Posts: 147
in Problem solving
I'd not known much about vine weevil, I never hear much talk about it, but it looks as though they are damaging my bergenia. The leaves are tending to brownish/reddish and there are some notches in the leaves. they've not flowered very well before and this year none at all. It is in a number of places around the garden, front and back and all affected

 From youtube videos etc it looks as thought they are difficult to deal with. Can you dig out the soil and go through it to find the larvae?

My neighbour is widowed so I do a bit of gardening for her and put some of my excess bergenia in her garden probably a year last autumn and these have made a big patch of green glossy leaves and flower spikes aplenty.

Maybe if it is a problem, throw it all out and replant some next autumn?
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  • LynLyn Posts: 23,190
    edited March 2020
    Difficult  to say without seeing the problem.  If it’s vine weevil you will just be able to pull your plants away and they’ll come away from the soil because vine weevil grubs eat the roots away. 
    You can dig the plant out and look, you’ll soon see them. 
    They are fairly easy to deal with, at the end of March you can look on amazon or ebay and see Vine Weevil nematodes for sale, you mix it with water then water around the plants.
    they do work, I’ve had them before.  As long as you follow  instructions.
    they need to be applied twice a year so you do it again at start of October, that may kill off anymore that the weevil will lay through the summer. 
    Gardening on the wild, windy west side of Dartmoor. 

  • FairygirlFairygirl Posts: 55,117
    The foliage does go reddish brown in winter @berarde, so that's nothing to worry about  :)

    Adult vine weevil damage is seen round the leaf edges - small notches taken out.
    The larvae eat through the roots, as @Lyn says, so they often pull out the ground easily. You can sometimes recover the plant by washing all the soil off the roots that are left, and replanting.
    Plants in the ground tend to be less affected by weevils, unless you have a really heavy infestation, which you'd see in other plants. They're more often a problem with potted plants.
    I have weevils here, but I've never had them damage Bergenias.
    A pic will help though.
    It's a place where beautiful isn't enough of a word....



    I live in west central Scotland - not where that photo is...
  • LynLyn Posts: 23,190
    Same here Fairy,  I’ve just picked a few Aquilegia straight of the soil, no roots at all. 
    Gardening on the wild, windy west side of Dartmoor. 

  • FairygirlFairygirl Posts: 55,117
    Lyn said:
    Same here Fairy,  I’ve just picked a few Aquilegia straight of the soil, no roots at all. 
     :/ 
    I haven't checked anything for weevils, but there's a few new plants which haven't survived the winter.
    Serves me right for not taking cuttings.
    Such is life.  ;)
    It's a place where beautiful isn't enough of a word....



    I live in west central Scotland - not where that photo is...
  • berardeberarde Posts: 147

  • berardeberarde Posts: 147
    I've included some photos in my last post. The fairly healthy is about 2 feet from the better of the two failing plants, but neither has any sign of a flower. The third photo is of the worst one. I have bergenia in a number of different places all, except the first photo are in this raggedy unhealthy state. Some haven't been moved for a while, some I moved last autumn.

    Those I planted in my neighbour's garden the two last autumns are a large and thriving patch with plenty of flower. Hmm...
  • BobTheGardenerBobTheGardener Posts: 11,385
    The first two photos show equally healthy plants, the first is being sheltered and warmed by the house walls, so has stayed green while the second is more exposed and has turned the characteristic green/yellow/red in the frosts.  I'd agree that the plant in the third photo has been attacked by adult vine weevil and given the poor growth, probably by grubs eating the roots, too.
    A trowel in the hand is worth a thousand lost under a bush.
  • berardeberarde Posts: 147
    Thank you, any tips on how I can get them to flower, maybe some rose type fertiliser?
  • BobTheGardenerBobTheGardener Posts: 11,385
    A tomato fertilizer would be worth trying.  To promote flowering, a fertiliser relatively low in nitrogen (N) but high in both phosphorus (P) and potassium (K) is generally recommended.  Look for NPK ratios like 8:24:24 in general fertilisers.  It's also worth checking if a fertiliser mention 'trace elements'.  Most soils won't need these but the lack of just one vital element can cause plants difficulties, so you may as well use a brand which includes them.
    A trowel in the hand is worth a thousand lost under a bush.
  • Skylark001Skylark001 Posts: 75
    @berarde, well the 2nd and 3rd photos certainly show weevil presence, but the 2nd photo shows very little weevil nibbling.  Obviously the 3rd example has been badly infested, so I wonder how far it is from the plant in your second pic.  Number 1 is protected against a wall, so it's leaves haven't been subjected to winter cold and winds.  Because number 2 isn't badly nibbled I don't think the state of the leaves and the non-flowering is due to weevils.  It's more likely due to the positioning and/or the growing medium.  I'd take BobTheGardner's advice re. feeding them.  But also, as your neighbour's are doing so well, consider whether their positioning is better than yours.  Think: what's my neighbour's conditions in comparison to my own, and then try to recreate them.  Perhaps your specimens need to be moved elsewhere. 

    Re. dealing with weevils, I have had to become something of an expert on them, sadly, and can only pass on the findings of the Lord Heseltine's "emergency weevil summit" of several years ago.  The only products which will deal with weevils are now permitted to nurseries only, and they're expensive.  All the weevil pesticides which non-nurseries folk like you and me can purchase are ineffective and a waste of money, which was the reason for the summit.  Nematodes are a good IDEA, but in practice they are not feasible unless you're dealing with small pots.  University research has proven that at least a third of nematodes are dead-on-arrival at your door, they're also expensive, and they cannot be trusted to wriggle their way to every larva in the soil and then consume them all.  Anyway, your plants are embedded in a layer of small stones: if that layer is at least an inch thick then weevils won't be able to get into the soil to lay eggs and hibernate, and newly hatched weevils wouldn't be able to emerge from the soil into the big wide world to start munching.
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