Forum home Problem solving

Black twigs on in identified shrub / tree

Hi all

I'm hoping someone may be able to help me figure out what's killing one of our plants please?

we have a small tree / large shrub in a patio border. We recently moved into the house and haven't been able to identify it yet - we think it's possibly some kind of daphne as it flowered through the winter.

The tree had outgrown its stake and was struggling to stay upright so we re-staked it about 6-8 weeks ago. But I think my husband was a little forceful in trying to get it upright again and put it under a bit of tension.

maybe a month ago it started wilting with the leaves turning a dark green / purple and some going brown. Then a week ago I realised that some of the twigs have turned black - some have tiny black spots where the leaves would have joined the stem, some larger black patches and others are almost entirely black. The outer layer of the twigs has started to split and peel (the twigs were previously soft and smooth, with a purple / green colour).

yesterday we noticed that the trunk now has large vertical cracks in it. The area around those cracks feels a little spongy if you press it.

does anyone have any ideas as to what we might be dealing with and how to save the plant?

we're novice gardeners and kind of at a loss. A friend suggested a winter wash and general fungicide treatment, so happy to give that a go.

oh and the plant is up against the edge of a wisteria that is just starting to establish itself properly - so we're really worried about whatever it is spreading!

any help at all would be greatly appreciated.

thanks

Posts

  • Sorry - just to add, black spots have also now started appearing on the leaves. But I'm confident it started on the twigs.
  • LynLyn DevonPosts: 21,137
    A photo would be a good idea for identification purposes.
    Gardening on the wild, windy west side of Dartmoor. 

  • BorderlineBorderline Posts: 4,687
    edited April 2018
    Agree with Lyn, let's see what type of shrub you have. Does sound like a part of the trunk/branch may have cracked and had gone un-noticed for a while and may have been infected. The sequence of events like blackened ends and cracks on branches and brown leaves are die-back symptoms but, why. An infection or a split branch. Without a photo, it's hard to know what is the best way with dealing with it.
  • edited April 2018
    Thank you both for your responses, and apologies for the lack of photos - I'm new so unsure of forum etiquette. 

    Here are some pictures, though I'm not sure if it's too far gone for easy identification! Previously, the branches were the purple colour in the last photo. The black branch is an example of the worst of the symptoms. Over winter it had purple flowers that dropped down at the end of the branches. 


  • BorderlineBorderline Posts: 4,687
    Are you based in the UK? I can't think of any shrub/tree that flowers in winter with a purple colour at the top of my head. You are right, the leaves are so badly damaged it's hard to tell if it is a Hebe shrub or not. The leaves and habit looks a bit like shrub called Phillyrea Angustifolia, but they don't produce purple flowers. 

    Is this shrub growing indoors or over a type of cover? It has out-grown its original spot which is probably why it's leaning forward. The split trunk is an issue, it's probably picked up a fungal infection and this is now causing die-back.

    The base seems to be completely filled with Buxus Sempervirens, which is competing with the root area. I have to say, without knowing what shrub it is, it has not been happy for a while, and needed to be re-located or pruned back. 
  • Thanks Borderline.

    yes, I'm in the uk. The re-staking was shortly before the cold weather hit so we wondered if it had suffered / been made more vulnerable by being messed around with and then subjected to such cold weather for such a sustained period.

    It's placed outdoors but in the corner of a walled garden.

    the box hedging runs all along the front of the border - it's to a depth of about a quarter of the bed. I don't know for sure, but believe the box is relatively new - planted maybe 2-3 years ago.

    we had thought the tree / shrub needed pruning but as it was in flower when we moved in had wanted to wait until the flowers died back to do anything drastic to it. It seemed a pretty happy plant (though we really don't know how to assess that, bar the fact it was generally green, leafy and flowering vigorously!) until the last few weeks.

    if we're going to try to save it, is our best bet a course of treatment for some general fungal infection do you think?

    is there any advantage in pruning it back pre-treatment or trying to print out the worst of the affected branches?

    thsnks again!
  • BorderlineBorderline Posts: 4,687
    edited April 2018
    I had another look at your damaged shrub and tree and now believe it could be Polygala Myrtifolia. Please Google to see if you recognise the flowers. It’s quite a tender shrub that is very likely reacting badly to the recent cold weathers over the last few months. 

    I think you will need to prune it back quite drastically the damaged branches to limit further damage. At least back to areas where the leaves look decent.

    Try to clear the base area up and lay a thick layer of mulch. This may help to protect the roots if it’s only frost damage which normally affects the tops and tips of plants. I don’t know the aspect and also where you are based, but for the future, you might want to invest in some fleece covers in case of extreme weather.

    If it is this shrub, I don’t think you will need to treat for fungal infection yet. You need to concentrate on getting the dead branches prune off first. I reckon it’s bad frost damage. But keep an eye on the branch cracking. That is a risk for infection.
  • fidgetbonesfidgetbones Derbyshire but with a Nottinghamshire postcode. Posts: 16,462
    edited April 2018
    The overall tree picture looks like it has been frosted. A lot of plants this winter were growing in mild weather and then got caught. The top of my Garrya elliptica looks similar, and it is bone hardy.  Just prune back gently to get rid of disfigured leaves. I am leaving my Garrya  alone until its normal tidy up  later on in the summer.
Sign In or Register to comment.