Trouble with Wisterias - growth slowing down, leaves curling

Hi everyone,

I'm hoping I could get some advice on these two Wisteria brackybotyrs (silky wisteria), photos below.

They were planted about 4 years ago and have been doing well - flowering every year.

Last year I noticed some of the new foliage which emerged in spring was curled up and hard, and the leaves quite small. It didn't seem to put on new growth with the expected vigour. Some of the foliage is fine but about 1/4 to maybe 1/3 of it is as pictured.

This year it's done much the same, although it did flower a lot of the new growth in spring looked stunted. It did eventually put on long shoots so I pruned it in the usual way in late July, but unlike my other Wisterias elsewhere in the same garden, nothing then grew from the pruned ends.

I have three other wisteria in the same garden which get the same treatment and are doing fine.

They're growing over the archway and iron fence as you can see, in full sun. I topdress them with leaf mulch each year, ocassionally feed with a tomato feed (esp in spring), and water fairly regularly. I prune them twice a year in the recommended way - cut new growth to 4 or 5 buds in later summer, then to 2 buds in Jan.

Any idea what could be going on? I'm concerned they're slowly declining and determined not to loose them.

 

Drought probably. You don't say where you are, but many areas of the UK have had much less rainfall than normal since February and it's having an effect on our plants.

 

I would have thought that too but the leaves went like this as soon as they emerged in spring, they never looked healthy from the outset. It's had plenty of water too - same amount as the other wisterias in my garden (which are doing fine).

In the North East by the way.

 

Hi

Would say cold winds .. as it is exposed on all sides

 

I am no expert at all in Wisteria ( never grown them) but those leaves look remarkably similar to how the leaves on our Veronica Spicata bush were earlier on in the year. I thought it might be some sort of disease so picked off all the funny curled leaves .@Spruce could well be right as we’ve had some bitter winds too, being in the North East, and then the red hot summer, plants don’t seem to know whether they’re coming or going.
Just edited to add that after reading @pete post I meant to say I did think either disease or insect might have been the cause. Our Veronica did grow in as normal after the supposed “ cause” moved on….

 

To mit looks like insect damage of the new shoots as they emerge, the leaves then grow but are distorted.
The fact it made normal growth of the long shoots suggests that by that time the pest had gone.

The missing new growth after the pruning could suggest the plants are struggling a bit with the dry weather.

Is that spot a bit dryer than where the others are or are the others better established.