MB Fig - blackening leaves?

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Pearcy001
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MB Fig - blackening leaves?

Post by Pearcy001 »

My Morton Bay seems to be having some leaf damage suddenly occur.

It seems to be beginning in the centre of the leaf and growing outward.

I think it is just sun damage but am confused as throughout last summer it got much much much hotter then it is now and didn't happen then.

I believe I may have let the soil dry out a bit too much the other day, so that is probably the cause. It's since had a good soak in a tub of water.

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If you recognize it as something different please let me know.

Cheers,
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Re: MB Fig - blackening leaves?

Post by Pearcy001 »

Looking like a may need some help with this one guys.

Since I posted this it has sat in a tub of water for around 12 hours and not had the soil dry out once receiving continuous checks... Yet the blackening of the leaves appears to be spreading?

Another couple of leaves have begun to blacken around the centre of the leaf and the couple that only had a bit have gotten bigger.

Can anyone offer some advice? I was under the impression that it was due to a dry substrate but even the 12 hour bath a couple of nights ago it doesn't seem to be improving.

Cheers,
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Re: MB Fig - blackening leaves?

Post by Jarad »

How damp is the soil? It could be over watering.

From what I've been reading it would appear that pretty much all trees are able to stop absorbing water when they are full except for some species of ficus. As the ficus absorbs water, it sends it to it leaves. The leaves thenfill up, and when they are too full, cells within the leaves burst causing the blackening.

But don't forget, I'm a noob.
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Re: MB Fig - blackening leaves?

Post by Pearcy001 »

Haha don't worry about the noob part mate all ideas are welcome on any of my posts. I also have it on good authority that you've been at this longer than I haha.

I'm only guessing here, but if your theory were correct I think it would have happened closer to winter when it was copping full rain every day, unless if has only just filled up recently?

The soil it came in is full organic and does hold water but it also was quite dry when the blackening began.

I only have a small collection so before I water a tree (well 90% of the time) I checked that the soil isn't still wet before I water.

The only things I have done differently that i can think of is up the fertilizing schedule, but this began weeks ago and if we're the cause would have shown signs long before now. (Plus this is a ficus, if my other species can cop it than this certainly can haha)

So much confusion...
Last edited by Pearcy001 on November 17th, 2015, 9:51 pm, edited 1 time in total.
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Re: MB Fig - blackening leaves?

Post by Jarad »

Well, it doesn't look fungal, otherwise there'd be rust all over it. And I doubt the roof of your house would be humid enough.

I don't reckon it's leaf burn, because the leaves don't look burnt. And the water would evaporate before it has a chance to burn.

Over-fertilizing a ficus is quite difficult. I give my PJs fortnightly (sometimes weekly :lost: ) osmocote all purpose. And the occasional Charlie Carp.

It doesn't look under-fertilized because the leaves look healthy other than the spots.

If it was mine and it was only a few leaves, I'd slip pot it into some soil that drains better and just pick off the problem leaves. Then wait to see if the spots show up again.
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Re: MB Fig - blackening leaves?

Post by treeman »

Sunburn 100%.
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Re: MB Fig - blackening leaves?

Post by Pearcy001 »

Thanks treeman that's what I thought too.

The real confusion came from the fact that it was in the same spot last summer, under a much much hotter sun than we have at the moment and there was no signs of burn then?

Oh well. I'll move it to a shadier spot to recover. Thanks for the confirmation.
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Re: MB Fig - blackening leaves?

Post by Reece »

treeman wrote:Sunburn 100%.

Yeah I was told this by the president of my club last year......
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Re: MB Fig - blackening leaves?

Post by Axeman »

I have a few MB figs and that is Sun burn..
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Re: MB Fig - blackening leaves?

Post by treeman »

Pearcy001 wrote:Thanks treeman that's what I thought too.

The real confusion came from the fact that it was in the same spot last summer, under a much much hotter sun than we have at the moment and there was no signs of burn then?

Oh well. I'll move it to a shadier spot to recover. Thanks for the confirmation.
Pearcy. There's no need to move it under cover (not yet anyway) It's caused by a very bright hot day all of a sudden in spring before the tree has had a chance to adapt. Or it is caused by moving a tree from shade to sun. The new leaves will be adatped to handle the sun without burning if they actually develop while in the sun.
The way to tell sunburn is that it always appears where the light strikes it square not where the leaf curves away. If you look at your pics you'll see what I mean.
One of my figs was badly burned last month when I moved it out of the g/house. Almost all the leaves fell off. However I left it where it was and the new leaves are/will be fine from now on. It goes back to semi-shade once the temps reach 35 or so mainly because in Vic they are come with low humidity. (which is the big problem)
Last edited by treeman on November 18th, 2015, 2:39 pm, edited 1 time in total.
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