Portugese Laurel Issue

bazbrady

So i have browning on my portugese laurel,its down about 5 years the last 2 years its lost a fair amount of leaf due to this browning,i asked a few people and was told its downy mildew and to use Proaxinal potato blight spray on it,i did last summer and seems to be recovering albeit slow and alot the leaves on the bottom are gone.Its starting to show signs again as below,can anybody tell is it 100% downy mildew or is it some other form of stress that its loosing leaf,there was a rough hedgerow behind it which may have hindered growth by robbing moisture ,reducing airflow amd light but ive cut this down just the winter gone,any advice will i just give it another few sprays this season and plenty manure feed?

bazbrady

sorry this is another picture also,thanks

robairdmacraignil

It does not look like downy mildew to me. I have a single Portuguese laurel shrub planted that is not part of a hedge and it has a lot of marked leaves. Here is a clip of it flowering. I put the markings down to the fact it is planted in a place with very shallow soil and it is just taking time to get settled in what is also a very exposed position. I think it will improve with time as the roots develop and the plants around it get a bit bigger and give it a bit of protection form the wind. Your situation is a bit different to mine in having a whole hedge of the plant but I see no reason that a fungicide spray designed to deal with potato blight would work on your hedge. The hedge near to it might have slowed your own hedge roots settling in and caused it some stress that would explain it not being very healthy. If you already used this spray and the fungus has grown back it is more likely to be resistant to the chemical that has already been used and a fungicide will also be damaging to beneficial fungi that would help your garden plants. If it was my hedge I would not spray it and I would not add manure as faster growth generated by high nutrient levels is said to be more susceptible to fungal disease. The lower leaves dropping off might be due to the way the hedge is pruned and you should try to have the end of your hedge slightly wider than the top so light can reach the lower leaves which will drop if they are shaded too much by the hedge growth higher up. Just keep the base of the hedge free of weed competition and maybe give it a bit of mulch when the ground is not too dry.

bazbrady

Thanks,Ive decided not to re apply the proaxinal spray and have just installed a dripper irrigation system the length of it and as i said cut down the hedgerow behind it,i think as you say its stressed,ive yet to prune the hedge,plan to this year to keep it at 5-6 feet,the lower base was very shaded by the removed hedge row,going to mulch in the next month or so.thanks