What is your experience with fungus gnats using Coconut Choir as rooting medium?

I had fungus gnats infestation using peat based soil. I had less than 60% rooting success. In my view fungus gnats seem to have a lot to do with it. I am going to start using coconut choir for the remaining few cuttings.
Is coconut choir immune to fungus gnats if nearby rooted plants in peat based soil have potential fungus gnats?

In my experiance, fungus gnats seem completely disinterested in coco coir. For me coco coir is the perfect rooting medium.

I can tell you my only gripe with coir. It is when it goes dry after a while and plant is in cup. Rehydrating is difficult because the water doesn't drain it just soaks. Some trees will rot because of this. It is very resistant to fungus gnats though.

Gnats are the worst, they do kill your chances at a higher rooting rate. My main gripe with coco coir is that no matter what variety I try rooting they have very thin and weak roots. I've tried plain water and also with light fertilizer and I get the same result. When the time comes to up-pot them is where I loose some.

Comparing coco coir rooting to sand, the roots are much thicker when rooting in sand or even in regular soil if they survive the rooting process.

 Thanks for your input, Simon.   Has this been your experience in side-by-side rootings of the same cultivar in the different mediums?    I'll give this a try tonight.

  Brian, to combat the wet coir against cuttings, I've tilted the cup at a 45* angle and drizzled the fertigation liquid down the side of the cup, maintaining the drier coir close to the cutting.  I have not yet lost a cutting due to rot using this method.  I also place the cup into a closed ziplock bag with just the cutting extending through the bag.  This slows evaporation greatly during the first few weeks of the rooting process.  When leaves push, I gradually open the bag to the atmosphere and begin the fertigation when required to maintain the low moisture level inside the cup.

I will tell you, the healthiest fattest roots have been direct rooting in pro mix hp. And no I don't get those huge roots in coir. However, I still get plenty of thin roots that are ok.

This year I've had the worse gnat problem ever using Pro Mix BX.
Really horrible, I've tried Neem Oil and Diatomaceous Earth and am not impressed with either one. I battle them and it seems to get better for a while and then a new batch returns. Rooting in Coco Coir and Long Spagnum moss has been no problem but they arrive when I up pot.
Really frustrating, but I feel I'm winning...but not by much
No More Promix for me

I use More Prom HP for a well rooted one year old plants in one gallon or bigger pots with no problem. Fungus gnats don't kill at that stage as is my experience. It is "in the cup stage" that fungus do their job of killing unless the rate of root growth is fast which helps the plant survive.

You can also mix the coir up to 40% chunky perlite if it is too wet for you, this provides excellent drainage but more frequent waterings.

James, thanks. You wake up so early on Sundays!
I was thinking of perlite addition but "chunky" is the word. Most bags available here from Miracle Grow or others have small perlite grains and half just perlite dust even if some bags are marked 'horticultural perlite'.

Akram,  Home Hardware carries the brand "Alltreat Farms" perlite and I find it has much less dust and better size perlite than the MG... When I sift a bag of MG perlite I would lose half of it.

Also when I am rooting in cups (with pre-dampened potting mix/perlite) I wrap the cups in saran and tie around the cutting which locks in the moisture for many weeks and keeps the gnats out. Nylon stockings work great too for the 6" green pots or 1 gallon pots. Since using them the last 3 years now I've had great success not loosing cuttings at the potting up stage due to gnats.

Tyler

Akram

I use mostly perlite with a little coir, never had a fungus gnat in my rooting, but that is because I root in a sealed Sterlite container (humidity chamber). No gnats can ever get in it. If you are rooting in a cup exposed to outside atmosphere then they have a breeding ground. But the gnats still do not appear spontaneously-there must be a source of organic matter somewhere nearby for the eggs to hatch or appear. I would focus on that. Even if you are rooting exposed to an indoor environment, if there are no plants around and no composted soils, where do gnats come from? Neither pro-mix nor coir are media that would normally host fungus gnats. Extinguish the source of gnats and you should solve the problem I think. Even after I up-pot i keep 1-gal plants under lights indoors, never had gnats get into my young plants because I keep my indoor environment bug free. I even have a worm composting tray in my basement, never had bugs transfer out of it into my plants.

Has anyone tried this stuff:

http://smile.amazon.com/Gardens-Alive-3440-Knock-Out-Granules/dp/B017RX3VO4?ie=UTF8&psc=1&redirect=true&ref_=oh_aui_search_detailpage

I had gnats this year, never more than 2 or 3 at a time, but I kept applying diatomaceous earth and it seemed to mostly keep them at bay.  I never could get rid of the last one or two, so I got this stuff.  It seemed to work...but I also got the gnatty soil outside as soon as possible so I don't know for sure.

rafaelissimmo
Yes, that kind of airtight system may prevent them from entering from outside. 
I always thought only raccoons were too cunning for some backyard gardener and for me too. After observing and dealing with fungus gnats I feel that they have a survival instinct that has made them cunning to some level. They do try to find ways to get in and stay to do their cycle and do the damage.

Hey Akram, I get up early everyday.

http://www.laportegardens.com/en/products/

Call those guys up and see if they have the chunky perlite, should be around 1/4 inch or so if they have it.  They are in Oreleans so its a bit of jog for you.  You could try local hydroponic shops, they usually charge more though but may be more convenient.

Thanks. I will contact them.Currently they are closed for the season.

Yes, hydroponic are costly. I paid $14 for a brick of Coco choir, though twice the size of a real brick. It turned out to be pressed long fibers and I did not like it.  Then I paid only $4 for two brick from Home Hardware that these two together were equal to the one from hydroponic.So the price ration was $14 to $4. I liked the one from Home Hardware.

So I only set up a few cuttings because I wanted to try my hand at grafting this year. These 3 cuttings are from the same mother tree, my Black Jack which is pretty vigorous, all roughly around the same diameter. The 2 on the sides are in damp coco coir and were put in 32oz deli cups on 12/25/15, the one in the middle was put in the same size cup but in old soil mix (lost a rooted cutting from last year and recycled the soil) but the thing is that I didn't do it until mid/late January 16. The 2 x-mas cuttings were washed and dipped in wax, the 3rd one was't even washed or dipped!!! I have noticed some spider mites but no gnats in the soil mix and no bugs at all with the coco coir and they are in the same humidity chamber.

Coco coir works great but liked I said, my only gripe is the weak roots. When time for up-potting, I use the same coco coir with the soil mix I choose for that rooted cutting. I don't really shake off the coir. What ever sticks, stays!!! I feel like the extra shock of completely new growing medium hurts its chances of surviving so I leave most of the coco.

One more detail, the middle cup has roots all around while the coco coir cuttings are only what you see...