How to treat silver spots on the back of my Lilly Pilly leaves?

[ElisabethR]

Hello, the leaves on the back of one of my Lilly Pillies has silvery spots. Does anyone know what they are?

 

 

[JacobZ]

Hi @ElisabethR,

Thank you for your question and welcome to the Bunnings Workshop community, it is fantastic to have you with us.

I believe you are looking at insect eggs, possibly aphids. You can see one in your first photo.

 
 

I'd suggest physically removing the eggs with a wet cloth and lightly spraying all the leaves with Yates Ready To Use Pyrethrum Insecticide.

Monitor the plant to see if any return and repeat the process where necessary.

Let me know if you have any further questions.

Jacob

[ElisabethR]

Thanks for your help Jacob! 

I had to use white oil on this plant last year and it almost killed it off, I've read some of the reviews and I'm worried Pyrethrum likely to do the same. Will it be alright or is there a better alternative for establishing plants?

[JacobZ]

Hi @ElisabethR,

Do you remember what time of year you applied the white oil?

A lot of white oil products don't recommend application on soft-leaved plants when temperatures exceed 30°C as it can burn the leaves.

Pyrethrum is similar in that it should not be applied when temperatures exceed 30°C. 

If you are concerned, manual removal is likely your best option.

Allow me to tag @Noelle to see if she has any thoughts.

Jacob

[Noelle]

Hi @ElisabethR and @JacobZ 

If spraying is recommended then it should be done at the coolest time of the day and only on days when the temperature is not expected to exceed mid 20s.Oil and water-based spray drops can act as magnifiers, greatly increasing the intensity of the sun and causing burning.

Spraying of the undersides of the leaves is usually suggested as that is where pests tend to congregate - misting the pests themselves is the most effective.

I'd be inclined to try an eco oil or neem oil, both of which are a little gentler on new growth than some other sprays.

[ElisabethR]

Thank you both for your advice!