Clematis Powdery Mildew

[Marb67]

Well. I am absolutely exasperated with this lovely blue rambling Clematis getting covered in mildew year in year out. I made sure the base was well moist and never to dry out (which causes it ) and yet again it has succumbed to it, affecting the stems and the flowers. I just give up

[Jungle Jane]

I’ve never watered my clematis’s,shrubs here only get rain when it rains,I’ve never had powdery mildew on mine. Clematis like their roots in the shade,sounds like yours is a few years old,have you tried not watering it & add a couple of inches of mulch on top of the root area. If the root area is in direct sun mulching will help keep the roots cool. Mine are planted in the north facing border,the roots are in the shade most of the day but the growth comes up & reaches the sunlight. Is your plants root area in direct sun,you can lay slabs or put big stones at the base of the plant to keep its roots cool. What kind of area is the plant in,is it overcrowded with other plants? Maybe air flow is the issue I don’t know?

[Marb67]

It's on a NE facing wall, huge convex concrete slab over the base to keep in moisture. It may be a few years old but it was getting this from day 1. Not much air flow as raspberry's and broad beans around it but the vine that has managed to climb the tree is also affected.