Bay tree with blue residue

Hi, sorry this is my first post on here, I have a five foot Bay Tree in a pot in the garden, the kind with a stem and a ball at the top , the leaves are starting to curl up and are covered with a blue residue, similar to washing powder, anyone able to help?.
I will post an introduction later, thanks
nev

 

Good evening Nev and welcome to the site. Any chance of some pics? I think what may be the problem is powdery mildew, but without images I can`t be 100%. It`s certainly some kind of fungus, so spray with a fungicide suitable for use on edible plants.:gnthb:

 

thanks for the reply , I will give it a try
nev

 

Hello Nev and welcome to GC.

I do not dispute what Dai says because he is one of our expert tree persons.

However, I am thinking it may be sooty mildew as opposed to powdery mildew (which I sadly have on my grape vine). My Bay tree (brought from the UK nine years ago) has sooty mildew. I get it every year, much to my dismay, and I wash every leaf with soapy water and mine is now 135cm tall in a pot on my kitchen patio ... so not a pleasant task ....

 

The only problem there Victoria is that sooty mould is black not bluish which powdery mildew is.:gnthb:

 

My 30+ year old bay tree gets a few bay leaf suckers each summer but this year, the attack has been particularly bad. These minute insects cause the leaves to curl up and distort. There were also quite a few whitefly. So today I gave my tree a thorough overhaul and removed every distorted leaf and then sprayed with Provado Ulimate bug killer.

Interestingly, some of the scaly deposits left by the bay leaf suckers had a bluish tinge and, possibly spread by rain, these had led to tiny, granule-like blue deposits on some leaves, very similar to Nev's description.

So my guess is that bay leaf suckers are at the root of the problem. I shall certainly operate a "zero tolerance" approach to them in future.

 

Surely " Bay Leaf Suckers " turn the leaves yellow first off? Nev didn`t mention that.:thumb:

 

Hi Dai

Bay leaf suckers suck the sap from leaves and this causes the edge to curl. They then lay their eggs inside the curl and the youngsters continue to suck the sap from the leaf when they hatch out. The leaf can continue living on the tree for months and months but the curled part is discoloured and the whole thing looks a bit sickly. Bay leaf suckers don't want the leaves to turn yellow and drop off because their eggs are inside the curl! Somehow, they distort the leaf just to the right degree. Eventually, it'll fall but sometimes, they hang on even through the winter.

 

http://www.gardenersworld.com/how-to/problem-solving/garden-pests-bay-leaf-suckers/

That`s not exactly what it says here.:thumb:

 

But this shows exactly the kind of deformed leaves I've been picking off my bay tree for an hour or so this afternoon. On my tree, the suckers seem to attack only the young leaves.

http://www.sbpi.co.uk/PestControl/BaySucker/tabid/79/Default.aspx

 

That damage is a lot differant to the link I posted Flinty. I concede defeat.:lollol::lollol::gnthb::flag: