New eucalyptus tree has strange leaf markings

[OranaGardener]

Hello, I bought a small eucalypt last year and it's grown quite quickly but its new leaves have this red blotchiness. It is very smooth, no bumps or spores. Do you know what it could be please?

[EricL]

Hello @OranaGardener 

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

It's possible that the tree is not getting enough water due to the brown ridges appearing on the edge of the leaf. Have you changed your watering habits lately? I'm a bit hesitant to diagnose it as a fungal infection as the leaf appears to be intact with no bumps, bruises or spores. 

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

If you have any other questions we can help with, please let us know.

Eric

[OranaGardener]

Thanks, Eric. I'm fairly sure it's not lack of water. In fact I was wondering whether it could be from over-watering?

[mich1972]

Good morning @OranaGardener @EricL The red spots looks like a fungal / bacterial infection . Does your soil get really wet ? Too wet maybe ? I want to wait until @Noelle has a chance to look at this. 

[OranaGardener]

Hi Mich,

The soil is not naturally water-logged or even damp but I may have over-watered it by hand. It doesn't seem like a fungal infection as the leaf is very smooth. This morning I noticed that the newest tiny leaves are dying.

[JacobZ]

Hi @OranaGardener,

Do you have any photos of the actual tree? Are there other things that don't seem normal with the tree? On the branches or the trunk?

Can you take a photo of one of the older leaves next to a red one?

Do you know what species your eucalyptus tree is? 

Any more information you can provide will help diagnose the issue.

Jacob

[OranaGardener]

Hi Jacob,

My tree is a Corymbia - Flowering Gum, and is just over a metre tall. It's been in the ground for 11 months and has more than doubled in size in that time.

Here are a couple of photos of it in situ and a couple of it's leaves.

All of the new leaves are affected.

 

 

 

 

[Noelle]

Hi @OranaGardener 

I doubt it is disease or fungal related as the discoloration is in the leaf rather than on it. It almost looks like it is something environmental caused by the tree not liking something about where it is growing. Could it be that the new growth has been exposed to frost/cold winds? If it is just the newer softer leaves and shoot tips affected then there's been an 'event' of some sort that could be the likely cause. Without being able to see the tree in its location, it's a bit hard to diagnose.

May I suggest using a seaweed tonic once a fortnight diluted to the colour of weak tea, to see if this builds up the strength of the new growth.

[OranaGardener]

Thanks, Noelle,

It has been windy, but not cold. I'll try with the seaweed tonic and let you know how it goes.

Thanks for your help everyone, I really appreciate it.

[JacobZ]

Hi @OranaGardener,

@Noelle's advice is always good and I'd suggest in this instance the best course of action.
 

Purely for your interest and that of any readers, while looking into potential causes for the red on your leaves, I have found some mention of Anthocyanin, which is a plant pigment similar to Chlorophyll that is responsible for red tones. There are scholarly articles that are unfortunately hidden behind paywalls that seem to indicate this is a natural mechanism of protecting young leaves from high levels of sunlight.

Seeing that your particular species of eucalyptus tree has quite a lot of red tones, I suspect this pigment is quite present in your tree and the red on your leaves might be a natural way of your tree protecting young leaves from sunburn.

Just some food for thought.

Jacob