Powdery Mildew?

[parkgate]

The Laurel Hedge that I planted in February of this year (trees 5 -6 ft in height) is now showing signs of withering leaves with a white powdery substance on the leaf underside, and I believe this to be powdery mildew - unless anybody has a different opinion.

 

This is a shame as the hedge was looking magnificent and has sprouted healthy growth throughout summer.

 

I think the situation is becoming worse. I wonder what is causing this, and if it is a serious condition, and more importantly what the remedy is. Admittedly, the trees were planted quite close together to create a privacy screen.

 

I have watered the trees at ground level throughout the hot dry summer, via a soaker hose, and they have been fed Miracle Gro every 2-3 weeks.  We are quite alarmed by this situation and don’t want to lose the hedge.

 

Do I need to call in a specialist?

 

Please see photographs attached.

 

Thank You and Kind Regards.

 

 

[openspaceman]

Are you sure that's not woolly aphid, it looks a bit fluffy for mildew

[Peasgood]

Looks like mildew to me.

Potassium bicarb is a reasonably friendly remedy that is worth a try, I use 15kg in 1100 litres if you want to work out concentration levels.

[parkgate]

Thank you for your replies.

 

Do the affected leaves need to be cut out and destroyed (there are many of them), or with spraying, are the leaves likely to recover?

 

Is the disease “life threatening” to the plant.

 

and do you recommend I bring in a specialist to undertake the spraying?

 

Regards,

[Peasgood]

No need to remove infected leaves unless you are cutting the hedge anyway. The worst of the infected leaves won't recover but the plants won't die from it.

You do not need a specialist but if you want to have somebody do the job for you a gardener should be able to.

You can just go to the garden centre and buy a squirty bottle of fungicidal treatment  and do it yourself.

[parkgate]

Peasgood,

 

Thank You.

 

Is it better to remove the infected leaves to encourage new growth?

 

Regards,

 

[parkgate]

I have consulted a tree surgeon and has recommended that I spray with a combined fungicide / pesticide spray (as there are also signs of aphids) and visit a garden centre for their advice on what product  to use.

 

Do you think “Top Rose, 3 in 1” would do the job?

[parkgate]

Sorry meant Rose Clear.

[parkgate]

Just an update on this - I hired a professional Plantsman to take a look at the trees.

 

His verdict was too much nitrogen applied in their first year - the roots cannot keep up with the leaves.

 

He recommended bonemeal and composted bark around the base of each tree and to lay off the feediing until next spring.

 

He pruned the trees and they are looking a lot better.