seanabc
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Yellow leaves on Ficus Retusa

I bought my first bonsai tree last Monday; a seven year old ficus retusa. Everything was going fine until Sunday morning when I found two yellowing leaves on it when I woke up. I cut these off. Then this morning I found another two leaves, one yellow and another starting to go that way. When I came home from work the second leaf seemed to be more yellow than this morning.

I have watered it twice since I bought it. The shop owner had watered it on Monday and told me not to water it for a few days. I waited until Thursday to water it the first time which I did by sitting it into a bowl of water for about ten minutes. I repeated this again on Sunday. Also I mist it every day.

I keep the tree indoors. I don't have very good natural lighting, so I leave the fluorescent light on in the kitchen and leave it on the kitchen counter when I'm at work. I then put it in front of a fluorescent desk lamp on the coffee table when I get home in the evening. I keep it away from the window because the light it would get from there would be quite dull and it could get a draft. I live in Ireland (I don't know what my zone is) and the weather is starting to take on more of a wintry hue to it.

I pruned it on Saturday. I removed one branch from the top because I thought it needed to be thinned out a bit. I also wanted to take a couple of cuttings to see if I could get them to root. Could this have put it into shock?

I have noticed insects moving about in the soil. They looked to me like ants. I think I saw one of them flying away. Is it bad under any circumstances to have insects in the soil or does it just depend on the insect in question? I thought they might have some role to play in aerating the soil so I didn't panic too much when I saw them. I have been concerned though to see bite marks being taken out of my leaves. It only affects a couple of leaves but clearly something has been eating them.

I have also noticed what look like specks of dirt on the leaves which I have wiped away with my finger. They don't seem to be alive, ie I haven't seen them moving but I don't know what they are or how they got there. Again I couldn't call it an infestation, but if I examine the leaves carefully I can usually find two or three of these little specks, usually on the top of the leaves.

I've been googling all day about yellowing leaves and have narrowed the possibilities down to either watering it too much. Or not enough. Or getting it too much light. Or not enough. Or the insects. Or not! If anyone can give me any advice I'd really appreciate it. I've heard that fig trees are pretty indestructible so it'd be really bad if I couldn't keep it alive.

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Gnome
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seanabc,

I doubt that watering is the issue. It does not sound as though you have let it dry out and over-watering is not likely to be the culprit either with only two waterings. Do you feel that you have a good grasp of basic watering practices? Have you read the general growing sticky located at the top of the forum? Most prefer to water from above but I don't think you have caused this by two immersions.

Nor do I think that too much light is the problem. I keep mine in full sun during the summer and they seem to thrive. I suspect that it is the low light condition. I have often read that Ficus tend to drop their leaves when moved to a new location under different conditions. My experience has been different but I only grow one variety of one species. All the same I never think it is a good idea to move a plant around as much as you have been doing. Try to find a permanent spot for the tree. The more light you can manage the better.

You may have fungus gnats. Is your soil rich in organic matter or is it gritty with a large percentage of inorganic material? The larvae of fungus gnats live in moist organic soils and can cause damage by feeding on roots. This does not explain the leaf damage though. Google the term and see if what you discover matches what you are observing. Any insect that I cannot identify is suspicious.

Norm

alexinoklahoma
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Location: Central Oklahoma

Ficus, in general, *will* yellow/drop leaves at the drop of a hat whenever their environ is changed. Even from being moved from one side of a room to the other, IME. Not unusual, not harmful, not a worry. My bigger tree (6-7' tall) yellows leaves each time I rotate it in the corner it sits in ;) Ditto to all gnome said....

Establish 'basic' good care ,if not already doing so, and tree should acclimate to the new home shortly. Its not unheard of for a ficus to drop entire set of leaves before settling in, I believe. Bugs on a few leaves aren't a big deal, and are easily taken care of :) About the worst thing for a ficus is for it to be in soggy soil, fwiw (overwatered, especially).

HTH,
Alex

seanabc
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Location: Dublin, Ireland

From what I've been reading about the yellowing leaves the last couple of days, I'm relieved to see it's not as serious as I first thought. In fact, in total only four leaves went yellow over the course of two days, but when I saw it I just thought the worst! Anyway there have been no more today so maybe it was just settling in.

I read an interesting explanation on one page I googled. It said that when a ficus is moved it sheds leaves that are no longer correctly angled to catch the light in order to grow new ones that are facing the right way. What do people think of that as an explanation? I had been moving it around a lot within the flat since I got it.

Since I got the tree a lot of people had advised me to remove the moss. I finally did it this evening. When I removed it I found the most disgusting piece of larvae ever. It was white, about half an inch long and curled up at the base of the tree. I was seriously freaked out by this! I removed it with a spoon as I wouldn't be able to touch it. When I had a closer look after I saw a much smaller larvae crawling around too.

How serious is this? And what can I do to get rid of them? Apart from any damage they might be doing to the tree, my phobia of insects is more serious than I thought!

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seanabc,
I found the most disgusting piece of larvae ever. It was white, about half an inch long and curled up at the base of the tree. I was seriously freaked out by this! I removed it with a spoon as I wouldn't be able to touch it. When I had a closer look after I saw a much smaller larvae crawling around too. How serious is this? And what can I do to get rid of them?

The most obvious thing is to remove them by hand. Gently probe the first 1/2 inch or so of the soil and look for more.

The most drastic measure would be to re-pot. But since this is a new tree and you are new to bonsai I am reluctant to advocate this remedy.

I wonder about the possibility of forcing them out with one more watering by the immersion method. If you submerge the pot to the rim and leave it for a short time you may force the larvae to the surface. What do others think of this approach?

The only other thing I can think of is to apply some sort of pesticide, not necessarily a synthetic though. Usually an ID is the first step if you want to take this approach. You have to know your enemy. Do you have Japanese Beetles in your area?

Norm

alexinoklahoma
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Location: Central Oklahoma

*Definite* issues when you have 'grubs' within the pot's soil, IMO. June-bugs, Japanese Beetles, and a few other types of 'grubs' all statrt of like this, and they do eat tender roots ;) If you think you have more grubs, either repot sooner rather than later or get something designed to kill such 'grubs' (no matter if it is 'synthetic, IMO) and rid yourself of those dang things... I find them in my yard as deep as 12-18" sub-soil, and heavy flooding this Spring did little to kill the grubs in same area, let alone 'forcing them to surface' by submersion. They're tough buggers, for sure, and move in extreme-slow motion, IME.

The good news is that 'typical' bonsai soils (nowadays) will not encourage grubs to seek housing sub-soil in pots :) I allow 'crawly' things in my soil (on most outdoorpots anyways) if I am reasonably sure that no harm comes from them - a natural thing per se, but I have advantage of showing bugs to my oldest son's girlfriend who is schooled in entymology ;) I have used weak bug-killer when needed in my pots without harm (known harm anyways).

With what I have heard so far on this, remove the moss (as done), get watering/lighting under 'control', find a single 'happy' spot for plant, a dose of bug-killer (permethrin is pretty mild overall, I think), then a repot if necessary to get proper soil within that pot (if that is an issue).

Alex

seanabc
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The most obvious thing is to remove them by hand. Gently probe the first 1/2 inch or so of the soil and look for more . . .
You have to know your enemy. Do you have Japanese Beetles in your area?
Norm,
It would be impossible for me to remove these things by hand! I don't know if it's a full-blown phobia but I'm definitely repulsed by insects and these larvae things in particular.

I followed advice that someone had given me to submerge the pot in a solution of soapy water. All I can say is that I haven't seen any insects moving about since then but on the other hand I haven't had too much time to examine the soil so far.

Regarding Japanese beetles, I just don't know. I'm brand-new to bonsai or even gardening so I don't know about things like that yet.
*Definite* issues when you have 'grubs' within the pot's soil, IMO. June-bugs, Japanese Beetles, and a few other types of 'grubs' all statrt of like this, and they do eat tender roots If you think you have more grubs, either repot sooner rather than later or get something designed to kill such 'grubs' (no matter if it is 'synthetic, IMO) and rid yourself of those dang things... I find them in my yard as deep as 12-18" sub-soil, and heavy flooding this Spring did little to kill the grubs in same area, let alone 'forcing them to surface' by submersion. They're tough buggers, for sure, and move in extreme-slow motion, IME.
Alex,
Do you think the soapy solution is enough? I was thinking of waiting another few days for the soil to dry out and dunking the pot for one last time in water with an insecticide added.

alexinoklahoma
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Joined: Mon Sep 03, 2007 12:21 pm
Location: Central Oklahoma

All I can offer is opinion, but I would not want to have soap within my soil ;) It is a surfactant that will (possibly) try and carry off dissolved 'nutrients' as it drains out, and there may be other reasons to not have a surfactant within the soil-mix. There's the camp that advocates no 'chemicals' whatsoever (boo-hiss, they say to anything non-organic!), and then there's those of us that will use minor amounts of appropriate insecticides (or whatever is needed) with respect for environment and all. Yep, I *like* using glyophosphate (sp?) for killing grass/weeds (with a small hand-sprayer, fwiw), and use other *.-cides as needed, but will *never* knowingly give a dime to Monsanto (maker/trademark-owner of Round-Up brand grass-killer and other things 'chemical'). 'Nuff said on that, LOL...

BTW, go to images.google.com and search/enter the bugs we are talking about and you'll get *plenty* of pics to show what we are referring to with June bugs/J Beetles ;)

Japanese Beetles are almost exactly like "June bugs" you see flitting around streetlights at night - the brownish 'beetles' that are always smushed on sidewalks where people walk often are the June Bugs. There's usually piles/carpets of 'em under streetlights as they will fly around the lights until they die, IME. Quite often, bats will swarm through the masses around the lights making for a neat display of predator-v-prey that can entertain kids (and me) for hours -> SWOOOOP go the bats! The 'Japanese' species is similar but 'electric green/shiny black of body/wing-protector flaps instead of brown (usually) like the June bugs (as popularly known here in the South).

Like I was saying, the grubs here lived through totally saturated soil for several months (record-setting rainfall for record setting length of time). I do not think that any 'mild soap' or water dunking will affect a June bug/Japanese Beetle to any great extent. A mild concoction of permethrin (sp?), which is a 'natural' derivative of a popular flower (an extract, per se) would likely kill 'em, and any other nuisance (and desirable) bugs within soil, no questions asked. Any runoff is not going to be a problem for the most part, but just take reasonable care to not overdo anything, read the labels), blah, blah. And take care not to harm any bees with all the probs *they* are having of late ;)

It may not be what I am thinking/postulating as far as 'grubs' go - but when in doubt, a mild insecticide is not going to take any reasonably-healthy tree to its grave, IME. It is not like you are pouring straight diazinon (I miss *that* poison!!!) into the groundwater supply in any way ;) It is fair to say the stuff is safe enough if not used stupidly (bluntly put!).

Also, you will never see any grubs moving around just by looking...they do their thing sub-soil and only come up when ready to fly away post-metamorph, I do believe. But bugs ain't my specialty in any way. I tend to leave 'em 'til proven guilty; lots of spider webs are allowed on my outdoor stuff, and praying mantis' are *always* welcomed.

HTH,
Alex

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