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
A trowel in the hand is worth a thousand lost under a bush.
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 ....now 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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Thanks Fairygirl, I neglected to mention all of my Pieris are in pots.
Edd, how much bicarb to a litre spray gun please?
thanks
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 ....now 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.