# Avocado Plant



## Manette (Jun 4, 2010)

Since the fall, the avocado plant has had leaf damage (as shown in the pictures below) on some of the branches. I am unsure what this is caused by and how I can treat it.


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## MCW (Jun 6, 2010)

Manette said:


> Since the fall, the avocado plant has had leaf damage (as shown in the pictures below) on some of the branches. I am unsure what this is caused by and how I can treat it.



Hi mate. 
Difficult to be sure with pictures over the internet. Normally I'd consider a tissue test to get an accurate diagnosis. I gather it is only the older leaves being affected?
What I can say it looks like is Magnesium deficiency if in older leaves (which they look like), possibly salt (but doubt it in your situation) and possible Boron toxicity but I also highly doubt it.
Try small applications of Magnesium Nitrate or Magnesium Sulphate (Epsom Salts) and see what response you get. Magnesium Nitrate is preferrable in most situations. You should see an improvement in plant health within a few weeks, even if only from the Nitrogen component of the Magnesium Nitrate.

Another thing too, does this plant see much sunlight? What variety of Avocado is it and has it been grafted onto a rootstock? Does the plant show any type of growth, such as new leaves etc?

Also what fertiliser have you been giving it? Under good growing conditions with heavier croploads Avocados will soak up a lot of fertiliser. If all else fails apply small amounts of a broad spectrum fertiliser such as Yara Complex (I assume this is available in the US?). This product contains both macro and micro nutrients and is a good all round broadcastable (non fertigation) type fertiliser.

Hope this helps


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## Manette (Jun 7, 2010)

I gather it is only the older leaves being affected?
It is primarily the older leaves although some of the leaves have browning tips or light spots (see the photo). 
Another thing too, does this plant see much sunlight? 
No, it is in a north facing window. Much of the light was recently blocked by a new high rise. 
What variety of Avocado is it and has it been grafted onto a rootstock? 
It is a Hass avocado and it hasn't been grafted.
Does the plant show any type of growth, such as new leaves etc?
Yes, but it is not growing as fast as it did previously. 
Also what fertiliser have you been giving it?
It was repotted in the fall, which is the only time it was fertilized. The fertilizers were ammonium phosphate and ammonium nitrate. 
Thanks!


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## MCW (Jun 8, 2010)

Although difficult to tell from the photo the lowest leaves in the shot also look to have either a Zinc or Manganese deficiency or a combination of both.
I'd try to apply a broad spectrum fertiliser as mentioned above that contains a variety of both macro and micro nutrients. Many of these mixes do not contain Calcium which should be added once fruit starts to form. This helps maintain fruit integrity by helping cell wall strength.
The tree in your photo actually looks to be in pretty good health for basically an indoor plant.
Depending on how many inputs you want to pour into this tree and what you want to spend I'd look at maybe even a chelated liquid fertiliser. Be wary of putting too much Ammonium Nitrate on as excessive nitrogen can lead to vegetative growth and the energy isn't put into fruit.
To be honest though an indoor avocado plant is all new to me  I think it is actually looking very healthy and have seen worse trees on commercial orchards


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## Manette (Jun 9, 2010)

Thank you!


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## Manette (Dec 24, 2010)

*New Problem with Avocado Plant*

After treating the plant with a broad spectrum fertilizer, it looked much better for several months. However, in the last few weeks, the leaves have begun to dry out and turn a gray brown color at the tips of the leaves and near the stem (as shown in the photos below). 
Any ideas on what it is and how it can be treated?
Thanks!


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## MCW (Dec 25, 2010)

Hi again and Merry Christmas 
Glad your Avocado's health improved after some fertiliser even if only short term.
I have to be honest I'm not 100% sure what those leaf symptoms are although some of the leaves in your attached photos look slightly wilted and water stressed. I do think I have seen symptoms like that before somewhere though but can't remember what the cause was.
Is there any chance you have applied too much fertiliser? Smaller amounts often is the key observing plant vigour as you go.
I am replying on my phone so unable to see the images as clearly as I'd like but is it only the middle aged or young softer leaves being affected?
I won't be back at my office for another 4 days so am unable to check through my large collection of plant health manuals to give you a more accurate diagnosis.


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## derwoodii (Dec 25, 2010)

I'll offer another thought. 
Perhaps too much water is the issue. Hard to tell the difference of too little and too much H2O. Stick in ya finger see if soils damp or wet. Is the drainage of the pot working as well then let us know. MCW got ya back on this problem he well qualified in plant care n I see been your family physician for a while. I may just be messin the diagnosis mix but I seen droopy leafs like that in over wet house plants. 

Ha my history with Avocados a sad story to tell, I killed too many over a few years trying to get a garden orchard crop. To deep, to sunny, to hot to shady then chewed by sheep and now after 10 years of drought too dam wet.

Oh merry chrissy too


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## MCW (Dec 26, 2010)

derwoodii said:


> I'll offer another thought.
> Perhaps too much water is the issue. Hard to tell the difference of too little and too much H2O. Stick in ya finger see if soils damp or wet. Is the drainage of the pot working as well then let us know. MCW got ya back on this problem he well qualified in plant care n I see been your family physician for a while. I may just be messin the diagnosis mix but I seen droopy leafs like that in over wet house plants.
> 
> Ha my history with Avocados a sad story to tell, I killed too many over a few years trying to get a garden orchard crop. To deep, to sunny, to hot to shady then chewed by sheep and now after 10 years of drought too dam wet.
> ...



Good point mate. Avocados don't like wet feet and can be a candidate for root rot.
They are a very hard plant to get right in some climates. In our area the growers are currently selling their crop for AUD$2 a fruit however the croploads are so variable here from climatic conditions that people are bulldozing them out.


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## techdave (Dec 26, 2010)

*Probably nothing wrong with that Tree Nanette....*

I could walk down the road to wife's cousins orchard and show you a lot worse on trees planted and grown in the style of a professional grower from Fallbrook CA which is an Avo heaven!

Just remember they need GOOD drainage and it is easy to overwater them.

How hot is the coldest it gets in that window? (Nothing to do with your leaf browning, I am just curious.) Thank you 

Dave in Jamul CA


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## Manette (Dec 29, 2010)

Thanks for all the responses!
I applied fertilizer monthly as instructed on the package for 6 months (this may have been too long). 
Both the middle aged and younger leaves are being affected.
The pot seems to drain well, but the soil is damp after being watered four days ago. In the last 2 weeks I have been trying to water it less but it hasn't made a difference yet.
It hard to say exactly what the temperature range is, but it is probably around 45 degrees Fahrenheit without heat and 80 degrees with heat.


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