the first question is what they are.. are they flies or gnats?

or do you know they are flies?

does that pot drain .... when was the last time it was repotted.. how do you water ... how much light does it get? .. does the pot ever dry?

what if any damage do you see from the vermin?

ken

Yes, like Ken said - identify the insect before you start treating the plant with things that may have no effect on the "flies." You plant is not turning yellow because of a few gnats living in the organic material that is in the soil. it is probably tuning yellow because you have used dish soap and vinegar along with rubbing alcohol on the plant...

The soil looks really dry and the plant is sitting on a piece of furniture - does it get any direct light from a window? When you water the plant do you soak it thoroughly and then let it dry out before watering it again? How long have you had this plant in your home? It looks like it is responding to improper care (this is not an attack on you the owner, just stating what I see in the picture) and not a result of any "flies" you may have seen around the plant.

Hope this helps.

to me that looks like the bathroom sink ... and i think that might be adding to watering issues.. perhaps never really drying ... and also made me wonder about lack of windows.. as bath windows usually arent very big.. or not clear glass ... and though it might appear bright.. it might not be enough usable light for the plant ...

ken

Kinda hard to tell from only one picture. But honestly it doesn't look too bad. I think I even see new growth in the center and the soil looks to be a good chunky mix.

Be sure the pot has drainage and as mentioned previously, water all the way through (so water comes out the bottom). These plants also love a shower. So you can water it with your kitchen sprayer or in the bathroom shower. Then do not water it again until the soil is completely dry.

As far as the fungus gnats go, you may have acquired them with the plant or even with the soil. They thrive in damp soil so if the soil is not drying completely, it will be a haven for them. I would start out by just using some of those sticky traps that go in the plant soil to trap as many of the adults as possible. Don't use any more chemicals for a while.

Also, the posters above are correct, this plant likes a LOT of light. You don't want to put it in full sun or anything because it will burn the leaves but good bright light.

replying:

as a clarification:

the plant gets direct sunlight, it was on the sink as i had to water it, and then teturned it back to its place.

as youve said, its those gnats, ive seen them fly aroumd the plant and in the soil,

the soil drainage is also good and quick, it does take a while for it to dry untill the next time i wayer it, in comparison to other plants i own that stand in the sMe location .

it gets water as soon as i check that at least third of the top soil is dry.

never had this issue with this plant, untill untill recently, just as the seasons changed it seems..

as pops said: Then do not water it again until the soil is completely dry.

that is the key to beating gnats ... let the media dry ...

so you watering it when only the top third is dry.. is the problem ...

if you want to cut the cycle down ... repot it in fresh sterilized media ... so you are sure to get rid of all the eggs in the media ...

do not put close to any other plants.. unless you want to spread it around... and in fact.. if it were mine.. it would go outside until the problem is solved.. if you have that option ...

another trick of mine...is to water a plant heavily... and then take note.. and not water it again.. until the plant wilts ... you might find.. that with some plants.. that means watering once a month .. and others .... once a week ... never water on some random schedule ... the plant will tell you when it needs water ... too much water can be worse than not enough .. my usual system is benign neglect.. and since i instituted this method.. i havent ever had gnats again .. lol ...

ken

https://tipnut.com/sterilize-soil/

Thanks a lot, I’ll try that tomorrow morning!!

"I've tried the vinegar and dish soap trick- nothing." When using vinegar on plants, the poison is in the dose. IOW, a little mixed in water each time you water can help raise the pH of the soil solution (water in the pot) which can help if you have pH related nutritional deficiencies, but not with insects. The strength of the solution needed to kill bugs would be strong enough to injure insects. Dishsoap in any strength solution is harmful to plants because it breaks down wax in the leaf cuticle (skin) which prevents excess water loss, denies insect access to plant sap, and prevents disease pathogens from entering the plant. The only question is how serious the damage will be. If household cleaner solutions make their way into the soil solution, they destroy root lipid membranes and making water/nutrient uptake more difficult. It doesn't matter if 50 million people tell you they've done it and there is no problem, there's a problem. Appropriate/ inappropriate are not terms that turn on popular opinion or even consensus.

also the 70% rubning alcohol mixed with water, still nothing. 70% rubbing alcohol mixed stronger than 50/50 with water can also break down cuticular wax and destroy lipid membranes, so it should be kept out of the soil/ soil solution and when applied to leaves it should be diluted 1:1 or 1:2 alcohol:water.

is there a way to save the plant from them? If the infestation is serious (populations high) they will feed on living roots. Using a medium that holds less water is usually enough to limit their numbers or rid plants of them entirely. I never have gnat issues. Determine watering intervals by using a "tell" (see below). Unless a pot is 5" deep[ or less, the advice to water when the top inch or two of the soil feels dry to the touch is pretty much the recipe for over-watering. Using a "tell" keeps you apprised of what moisture conditions are deep in the pot, where it really counts. In most cases, roots in the upper third of the grow medium are devoid of the almost microscopically fine roots that do nearly all of the plant's heavy lifting. These heavy roots serve mostly as plumbing and anchorage and are normally removed during full repots to make room for more fine roots.

Using a 'tell'

Over-watering saps vitality and is one of the most common plant assassins, so learning to avoid it is worth the small effort. Plants make and store their own energy source – photosynthate - (sugar/glucose). Functioning roots need energy to drive their metabolic processes, and in order to get it, they use oxygen to burn (oxidize) their food. From this, we can see that terrestrial plants need plenty of air (oxygen) in the soil to drive root function. Many off-the-shelf soils hold too much water and not enough air to support the kind of root health most growers would like to see; and, a healthy root system is a prerequisite to a healthy plant.

Watering in small sips leads to avoid over-watering leads to a residual build-up of dissolved solids (salts) in the soil from tapwater and fertilizer solutions, which limits a plant's ability to absorb water – so watering in sips simply moves us to the other horn of a dilemma. It creates another problem that requires resolution. Better, would be to simply adopt a soil that drains well enough to allow watering to beyond the saturation point, so we're flushing the soil of accumulating dissolved solids whenever we water; this, w/o the plant being forced to pay a tax in the form of reduced vitality, due to prolong periods of soil saturation. Sometimes, though, that's not a course we can immediately steer, which makes controlling how often we water a very important factor.

In many cases, we can judge whether or not a planting needs watering by hefting the pot. This is especially true if the pot is made from light material, like plastic, but doesn't work (as) well when the pot is made from heavier material, like clay, or when the size/weight of the pot precludes grabbing it with one hand to judge its weight and gauge the need for water.

Fingers stuck an inch or two into the soil work ok for shallow pots, but not for deep pots. Deep pots might have 3 or more inches of soil that feels totally dry, while the lower several inches of the soil is 100% saturated. Obviously, the lack of oxygen in the root zone situation can wreak havoc with root health and cause the loss of a very notable measure of your plant's potential. Inexpensive watering meters don't even measure moisture levels, they measure electrical conductivity. Clean the tip and insert it into a cup of distilled water and witness the fact it reads 'DRY'.

One of the most reliable methods of checking a planting's need for water is using a 'tell'. You can use a bamboo skewer in a pinch, but a wooden dowel rod of about 5/16” (75-85mm) would work better. They usually come 48” (120cm) long and can usually be cut in half and serve as a pair. Sharpen all 4 ends in a pencil sharpener and slightly blunt the tip so it's about the diameter of the head on a straight pin. Push the wooden tell deep into the soil. Don't worry, it won't harm the root system. If the plant is quite root-bound, you might need to try several places until you find one where you can push it all the way to the pot's bottom. Leave it a few seconds, then withdraw it and inspect the tip for moisture. For most plantings, withhold water until the tell comes out dry or nearly so. If you see signs of wilting, adjust the interval between waterings so drought stress isn't a recurring issue.

Water When the Top Inch or Two of Soil is Dry?

I don't think so. Most growers unfamiliar with how water behaves in container media are prone to repeating the title mantra. But let's look at some facts. A saturated or partially saturated medium is limiting in a number of ways.

Roots need an ample supply of oxygen in order that roots can function normally. Saturated soil surrounding roots limits oxygen required to drive root function, thereby impairing root efficiency and possibly setting the stage for any of a number of fungal pathogens that thrive in anaerobic (airless) conditions.

Soil saturation limits gas exchange, so waste gases like methane and CO2 in the root zone are less able to leave the soil, also limiting root function

Soil saturation kills the fine roots that do the lion's share of work involving water uptake and nutrient distribution. When this occurs, chemical messengers tell plant central injury to the root system has occurred. Top growth stops immediately, because root growth always precedes top growth – the top will not grow if the roots cannot support the growth with water/nutrients. The plant is then forced to regenerate dead roots, using energy which otherwise would have been devoted to additional top growth, keeping the plant's systems orderly, keeping the plant wearing a 'healthy glow', and improving the plant's ability to defend itself. In short, the wasted energy would have kept the plant looking/ growing better, and healthier.

If a pot is 10” deep, the top 2” can feel completely dry to the touch, even while the bottom 6” is 100 saturated. That means 60% of the medium would be fighting you tooth and nail for control over the plant's vitality …… and this is the point at which you should water again? Does that sound reasonable? We don't care even a whit if the top 2" of the soil are dry. Roots there are largely plumbing and anchorage, with essentially none of the fine almost microscopic roots that do the lion's share of the plant's heavy lifting.

Ficus species are all good at retaining water in their roots in case of drought. That doesn't mean you should test them to see what they'll tolerate, but it does mean you can and should let the soil dry down so you can only detect moisture (by using a 'tell') in the bottom inch or two of soil. Let me know if you're unfamiliar with the term 'tell'.

Al

LIke others have stated, too much damp soil is the perfect breading ground for fungus gnats. I used Bacillus thuringiensis subspecies israelensis in the form of Mosquito Bits purchased from my local nursery which solved my gnat problem.

No matter what I've mixed with it, if I have a pot with any peat in it, that pot will have gnats, and I don't want dead bugs in my pot/house any more than I want live ones.

..... don't know how I forgot BTI bits/ dunks. I'm glad Jennifer mentioned it. Good goin'. While it's effective at keeping gnat populations in check, it doesn't fix the underlying attraction that draws them.

Al

I had the same trouble with this plant and followed the exact directions above and had great success. It is a beautiful plant and my newest that wasn’t cheap. Good luck!

I had a very bad fungus gnat infestation which I think came from an infested bag of potting soil. They are GONE now, and here's what I did. To get the adult gnats, I installed the yellow sticky traps made for them in every pot. They are attracted to the color yellow. Then, to take care of their root gnawing soil dwelling larvae, I mixed Bonide Systemic Houseplant Insect Control into the top inch or two of the affected pots' soil. So the yellow sticky traps, which became coated with dozens of those little boogers, took care of the current generation of gnats, and the Bonide took care of any upcoming generations. I am very glad that they seem to be gone, completely gone, after several weeks. It is also recommended to put sharp gravel or such as a top dressing to discourage adult flies from digging in to lay eggs, and keeping the plant a bit on the dry side. But I found the traps and Bonide to be the kickers in gnat eradication.