Today, one of those grapevines: Vitis vinifera 'Muscat of Alexandria', was the object of extra attentions, as it was of interest to a filming crew coming to the gardens.
|Vitis vinifera 'Muscat of Alexandria'
under glass at RHS Garden Wisley
Anyway, the reason we worked on the ‘Muscat of Alexandria’ today was the sooty mould growing on the excretions of brown scales (Parthenolecanium corni), one of the glasshouse’s longstanding pests.
|Parthenolecanium corni on Vitis sp
Some of the leaves were completely blackened, which, besides affecting their photosynthesising capacity (and occasionally clogging the pores on the underside), was rather aesthetically unappealing.
So we washed them, bucket of water and sponge in hand. High maintenance stars indeed!