How to stop Lily Pily leaves shedding?

[ss80]

 

 

 

  

 

  

 

 

Hi All, I am a complete noob with gardening and am totally unimpressed with the amount of work my house of 2 years is drawing. I have 40 Lily Pily trees that have grown quite tall in the last 2 years and are shedding a massive amount of leaves. I have replaced my red wood chips however they get covered with leaves within a couple of months. The sight of leaves rotting isn't very aesthetic and constantly replacing the red wood chips seems to be pointless.

It appears the leaves are getting eaten by something, reviewing the past posts, it could be a caterpillar however I couldn't spot any. I have been aware of the curly grubs in my garden but they are soil borne and have recently found that the grubs turn into some type of beetle eventually. I have spotted a few psyllids and a few insects that I do not recognize. I notice 2-3 trees are not as leafy as the rest, you can spot those in the pictures easily. I am looking for help from this awesome community for suggestions to reduce leave shedding and the overall effort with this backyard. I suppose a systematic pesticide will be required but I am so nervous about it, as I would like to use my garden for some edible plants down the line. 

[EricL]

Hello @ss80 

Welcome to the Bunnings Workshop community. It's sensational to have you join us, and thanks for sharing your question about your lilly pilly.

I suggest having a quick look at these guides - How to diagnose a sick plant and How to diagnose and revive a sick lilly pilly. It appears that you have multiple insect infestations occurring at the same time. I propose using Yates 50ml Advanced Garden Insect Killer to manage all the insects currently feasting on your lilly pilly. Please make sure to wear personal protections such as disposable coveralls, gloves, goggles and a Citeco Half Face Respirator A1P2 Kit. Please make sure to follow all the safety guidelines printed at the back of the packaging. For full coverage, please make sure to spray underneath the leaves as well.

Let me call on our experienced members @Noelle and @mich1972 for their recommendations.

If you need further assistance, please let us know. 

Eric

[ss80]

Hi Eric, thanks for your response. Yates insecticide was the one I was leaning towards. The only challenge is that its not systematic. As you can see from the pictures, the trees are quite tall and 40 in number, spraying will need to be quite extensive. Is there another insecticide that I can add to the soil or perhaps get injected into the trunks. Thanks again in advance!

[MitchellMc]

Hi @ss80,

You could consider using Yates 200ml Mavrik Concentrate Insecticide, but due to the number and size of the trees, it might be worth enlisting the services of an arborist tree surgeon specialising in tree care. The quantity of product you'd need would be best purchased in commercial quantities.

Although some leaf drop could be attributed to the insects, the majority of it is likely natural leaf drop as the leaves are overshadowed by the outer foliage. A tree will drop any leaves that do not have sun hitting them as they are a waste of energy. I suspect if you had the trees trimmed, it would allow more sunlight to penetrate the canopy and minimise the leaf drop.

Please let me know if you have any questions.

Mitchell

[ss80]

Hey Mitchell, 

Thanks for your insights. The Mavrik Concentrate is also for spraying onto the leaves and not for soil correct?

Regarding the leaf dropping/ trimming, I had the trees trimmed about a year ago to limit the overhang into my garden area, and since then they have doubled in height. Mitchell, Are you suggesting, I get it trimmed in a similar fashion or get it trimmed from the top. I am quite new to gardening world, so sorry if my questions are noobish. 

Regards,

SS

[MitchellMc]

It is sprayed over the foliage but is a systemic product, @ss80

Trimming the front of the plants could assist. However, as they grow taller, all the overshadowed leaves will drop, so if you don't need the new height for privacy, it might be worth reducing it.

Your questions a not noobish at all, and no need to apologise. That's what we're here for.

Mitchell

[ss80]

Mitch, if Mavrik Concentrate is a systematic product, then instead of spraying can I add it to the soil ? I application instructions for the product only talk about spraying.  I see new leaves in the trees now. If I add this insecticide to the soil, will it be safe to grow edible foods in the same soil?

Re trimming, the current height is optimum (approx 4m), I prefer that they don't grow tall, but I guess they will only listen to a trimmer blade. I am comfortable trimming from the garden side, however their current height is beyond the full size ladder Syneco 3.7m multifold ladder I own. I typically use it in the A form, so I can only go upto 2.5m or thereabouts. I can't reach 1.5m of foliage for spraying or trimming. I am more of a DIY person, but this seems to be beyond my limit. Do you have any suggestions with this situation? I will also get an arborist to run a quote for me, and with the quantity, my guess is, it won't be cheap.

[MitchellMc]

Mavrik Concentrate is designed for spraying on leaves for absorption, so adding it to the soil won’t be effective @ss80. Spraying also reduces the risk of contaminating soil where you plan to grow edible plants. You don't need to spray the whole plant as it will be absorbed and spread through it. 

For trimming, given your ladder’s limited height, a pole hedge trimmer could help you reach the foliage from the ground. 

Mitchell

[ss80]

This is helpful Mitchell. I have a pole hedge trimmer, thanks so much for all your answers!!! 

Have a wonderful day!