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Ficus

Posted by simsedward 6 -MI (My Page) on
Wed, Aug 11, 10 at 16:08

I have a fungus (black spot) on my ficus tree. It is potted in a well draining bonsai soil and I water it from the top with a fine mist only when the soil begins to dry out. I have purchased and applied an organic fungicide (EcoSmart garden fungicide). The tree is losing some leaves and it seems to be getting worse instead of better. My other trees (another ficus, 2 Chinese Elms and a Trident Maple) seem unaffected. Does this tend to spread to other trees? Can this eventually kill the tree? Anyone have any other methods for curing this? Any thoughts or advice would be greatly appreciated. Not sure how I got into this mess, but I'd love to be rid of it.
ED


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RE: Ficus

  • Posted by tapla z5b-6a MI (My Page) on
    Wed, Aug 11, 10 at 17:10

My guess would be that the spots and leaf abscission is a symptom of something else stressing the tree. The things that come to mind are a recent decrease in photo-intensity or photo-period, or a drought response due to a high level of solubles (salts) in the soil solution, under-watering, or over-watering, with the latter taking favored position, only because it's favored by the odds. If it IS being over-watered and weakened/stressed because of root issues, it's probably resultant of soil choice and exacerbated by watering habits. Fungal infections can much more readily gain a hold on weakened plants.

Obviously, you've said nothing to allow me to be reasonably sure of any one of the individual things I mentioned, but I wouldn't be so hesitant about saying the probability it's one of the lot is pretty high.

Al


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RE: Ficus

Hi, for one thing, I'm not sure I understand your watering technique. Do you just mist the plant, or water from e.g. a glass directly onto the soil? Misting will not water the roots properly (if the water ever gets beyond the top of the soil to begin with) and will absolutely encourage fungal growth all over the tree. Misting is meant to humidify, not to water, and water must be poured into the soil til it reaches the drain holes (but the pot should never sit in drain water because roots will rot that way as well). What kind of mix is it in - fast draining grit with a small organic component (as it should be), or 'potting' soil, which is usually 95% peat that holds water too longer and won't drain. Plus what kind of light is it getting? Is it outside for the summer (as it should be)?


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RE: Ficus

Hi
Thanks for the responses.
The tree is in grit with organic component. It does not get watered by misting. I never mist the trees in fact. I spray the top of the soil until the water runs through the drain holes. The pot does not ever sit in the drain water. I am pretty confident that its not a watering issue - definitely not overwatering. I have taken a few of the leaves to the local bonsai shop and have been told this is a fungal issue.


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RE: Ficus

  • Posted by tapla z5b-6a MI (My Page) on
    Wed, Aug 11, 10 at 18:28

Then you need to ask WHY this tree is having these difficulties. You have other trees nearby that have no fungal issues, and most Ficus aren't normally bothered by fungal infections unless they are weak. Describing light. how much air movement, fertilizer, pot depth & consistency of the soil (what is the grit and the organic component - how much of both)? - any other cultural conditions you think might be pertinent could reveal clues. Can you eliminate insect infestation as a primary factor that's weakening the tree or causing the spots? Who diagnosed the issue as fungal - a clerk, owner, someone you should place your trust in, or someone you're not too sure about. The latter is more common than the former.

An over-the-counter systemic fungicide with Tebuconazole in it (Bayer makes one) might be a good decision. They also make a 3-in-1 product with Tebuconazole, Imidacloprid, and a miticide (T-f?) that, if you aren't sure about the insects, can be used w/o issues on Ficus. If you buy it, get their concentrate.

Al


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RE: Ficus

Cool I will look for that product. I do trust the lady who gave me the advice (though she could be wrong). She is the owner of the shop and has been in business for over 40 years here. The tree is situated on a stand I built on the south side of my yard. it gets full sun and great air circulation. The tree gets fertilizer every other week.
I am not sure about insects, but I will watch for that.
Thanks so much for the advice, I want to save this tree.


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RE: Ficus fert

The fertilizer I use is a 7-9-5 ratio.


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RE: Ficus

  • Posted by tapla z5b-6a MI (My Page) on
    Wed, Aug 11, 10 at 21:43

W/o even knowing where you live, I'm going to guess you might be talking about Preeya? ;o)

Technically, the numbers in 7-9-5 are the %s of NPK by weight, not the ratio. The ratio would be 1:1.3:.7. You would be better off with a fertilizer in a 1:1:1 ratio, like 20-20-20, or even better, a 3:1:2 ratio fertilizer, like 24-8-16, 12-4-8, or 9-3-6. I've had excellent results with the 9-3-6.

Plants use about 6x more N than P, so it would be hard to justify using any fertilizer for containerized plants that supplies more P than N. Even 1:1:1 ratio fertilizers like 20-20-20 supply much more P than plants can use in relation to N.

Al


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RE: Ficus

Thanks again Al. I live in Southeast Michigan.


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Ficus Fungi

I found the 3 in 1 treatment from Bayer with Tebuconazole. I will apply after the soil dries out ( tree was watered recently). I will also get a 9-3-6. The fertilizer I used worked ok (not great) but it makes great sense that plants use more N than P. I appreciate your help Al. This tree is losing leaves like crazy and this morning I did notice some of the same leaf spot on my other ficus. Not sure what I am doing wrong as i have had the ficus trees outside through two summers now. Keeping fingers crossed on this one.


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RE: Ficus

  • Posted by tapla z5b-6a MI (My Page) on
    Thu, Aug 12, 10 at 15:09

Are they near or under any other (big - in the ground) trees?

Al


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RE: Ficus

I have no other trees in my yard. I did notice some mushrooms growing deep down under my fern leaves. the bottoms of the ferns also had the black spot. I removed the ferns and mushrooms and sprayed the area down with a fungicide. I applied the product from Bayer. Hopefully on the right track.


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RE: Ficus

Most of the leaves have fallen off now. My other ficus has it too. Good news is, it seems to be cleared up. The new leaves are forming already and they seem clear.


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