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morning all !! I have a forest flame quite large bush , been very healthy for years !! Over the last few months the leaves have gone black and also some have white spots on the underneath the leaf !! The black stuff is falling on my stone path and discolouring that as well !! Can anyone help ???


There's probably been some aphids on there, and sooty mould is growing on the honeydew left by them.  It should wash off if you hose them down gently, getting the underside of the leaves as well as the top surface. 

It won't wash down just tried !! Anyone else got any advice ?? 

You need to add a little fairy liquid to warm water. Gently though so ss not to damage the leaves.  A systemic spray in few weks will help prevent this for next year 


I too have this sooty mould on my Pieris, I did manage to get some of it off with a damp sponge but my plants are so big I couldn't possibly wipe down all the leaves. Verdon, may I ask what you mean by a systemic spray in a few weeks time?    

hi Meomye

I would apply a systemic insectide control the aphids that caused your sooty mould.

you can use a during the growing season to control aphids to ensure a clean bush next year

I seem to have this problem also, black top surface of leaves and on underside is white fluffy fungus like spots. The steams have also gone black. Any new ideas as what to treat this with? If anti fungal spray will work etc?

Still have sooty mould on two of my old large Pieris, now seems to be spreading on to 2 of my younger ones  gave it a spray of Roseclear a couple of days ago. How long does it take to show signs of improvement? Thanks 



Not sure Meomye as I don't use insecticides, but I'd think they act quite quickly -within a week perhaps. I'd be inclined to remove some of the affected foliage and dispose of it - not in the compost bin though, if you have one. Plants under stress are more likely to succumb to pests and diseases. Are your shrubs in soil that's in good condition, and not too dry or too soggy, with good airflow?

I'm sure someone will be able to offer further advice re the spray though. 

Thanks Fairygirl, I neglected to mention all of my Pieris are in pots.

Edd, how much bicarb to a litre spray gun please?


I have this problem on an established plant that were between two viburnum tinus which had been covered with mildew but are now removed.I wonderd if the sooty fungus was related to the mildew. 


Sooty fungus grows on the sticky sugars which have fallen on leaves after being excreted by aphids feeding on foliage above, so get rid of the aphids and you'll remove the source of the problem.  Some scale insects also produce this 'honeydew' so check for those too if you can't see any aphids.

Last edited: 07 January 2017 14:47:21

I too have this problem ! Black soot on leaves and branches of my MANY  pieris ......underside of leaf has small white rectangular stains . Impossible to remove the black soot with hose spreading to my choisya . Have sprayed with Roseclear but not much success. Resorted to pruning out sections badly infected My question is ....Is this going to eventually kill off my Pieris and Choisya:;??? 



I doubt this will kill off your shrub. If your spray is not working on it, don't worry. They seldom work on large areas. Concentrate on clearing any dead leaves lying around the base of your plant. Carefully scrape off the top layer of your soil and put new layer of mulch. Your plants are possibly stressed in the first place. It's essential there is good air-flow around your shrubs. You could re-prune your shrubs to give it more space between branches. Remember to thoroughly clean your blades and equipment afterwards.

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