Posted: 04/06/2014 at 07:17
I agree with Dave, honeysuckle leaves turn grey/black when succumbing to powdery mildew, before the fungus develops its powdery coat.
It affects honeysuckle that has been weakened by drought - honeysuckle, being a plant of damp woodlands likes it's feet to be cool and damp.
The leaves will go crispy and fall off but if you remedy the problem, plenty of watering (not soggy but moist) and shaded roots, the plant will recover.
No need to spray with anything. I believe Roseclear contains a fungicide so it will tackle mould-type problems, but the leaves that already have it will die, and if you cure the problem the new leaves won't get the mildew.
I bought a new honeysuckle this year and I think it had been a bit dry in the pot at the GC - a few weeks after planting it developed powdery mildew and all the leaves fell off, but it is planted in the right place, with shaded roots and moist but well-drained soil and it is recovering with new shoots appearing everywhere. The mildew only appears some time after the problem has occurred.
I do find that some garden centres like to solve your problems by selling you something!
Graham Thomas is a wonderful honeysuckle - I've grown one in a previous garden and it was one of the first plants I planted in this one. I find it takes a couple of years to get going, and then it's simply beautiful - such a good perfume and such elegant white and honeycoloured flowers - a very good choice