In a sealed environment (5Gal Bucket w lid) will the soil moisture and air humidity balance?

What is the best numbers to achieve best rooting?

Would you rather check the soil moisture level or humidity?

What instruments do any of you use to check these?

They will balance out. But even totally sealed and at constant temperature it would take months to reach uniform moisture in the soil. The air will be near or at 100% unless the soil is very dry, like if you air dry the soil in the sun for a few days. At any soil moisture that might support a plant the air will be 100% humidity.

Charles,
The optimum humidity for rooting fig cuttings is 85% to 90% RH. I measured the humidity in a plastic bag with healthy growing roots and damp long fibered sphagnum moss. The test instrument was a commercial/industrial Vaisala Humidity Meter with an accuracy of plus or minus 2%. The humidity inside the bag in the picture was approximately 85%.
 

I have never measured soil moisture, but in a sealed environment the humidity would never equalize unless you had free air exchange throughout the two different medias, like in an inflated plastic bag with fluffy sphagnum moss.

On the other forum there was discussion under the link:http://forums.gardenweb.com/forums/load/fig/msg012201035891.html?23 that was perhaps abaandoned or just "temporarily" stopped.
I tried to continue just a couple of days ago;

Almost full four years later, do we have a reliable summary of the indoor rooting chamber method?
What are the ranges of 5 key environmental requirements (humidity-air in container above potting medium level, light-quality and quantity, temperature, aeration-water to oxygen ratio, and moisture-water to potting medium ratio) for a successful rooting of fig cuttings?
There is apparently and ideal level, but also acceptable (low and high) levels for each of the above mentioned conditions within which the fig cuttings will successfully grow both roots and shoots.
My recent search outside of this forum has not returned a complete nor an easy to comprehend findings.
Not specifically for figs but rather for grape vines and fruit trees (I hope similar enough to figs) the following is what I gathered:
rooting cuttings of deciduous trees reported maximum growth in 25 C -30 C temperature range, another source states ideal temperature of 29 C.
Suggested moisture content of potting medium 55%-60%,
Highest amount of root growth was observed at moisture content just bordering that of expelling oxygen and causing rot. (how to safely attain it?) 
Humidity of the air 85%-95%, Light capable of supporting photosynthesis further helped root development of those cuttings that started leaves before or at the same time roots started.
To those seasoned fig rooting enthusiast that can or have measured any of the above, can you comment the values I posted above?
Despite my hardest attempt to attain and sustain stablility of the above 5 factors in sugessted or near ideal range, I find only rooting part responding nearly ideally.
After transferring cuttings to 24 oz cups into coarse pine bark, coarse perlite, peat moss (1:1:1) medium, the growth is still scattered; 50% cuttings are stalled with no top growth after 4 weeks, 25% are decently growing 2-4 leavs, and about 25% are drooping almost immediately after humidity bin lid lifted for ventilation.

Can_smokva,
Hopefully without hijacking this topic...
I did a lot of testing of temperatures and humidity last year for Fig Culture. I found that the numbers that were given in that post were similar to the numbers that I measured as optimal. 72 to 80 deg F. and 85% o 90% relative humidity at the cuttings produced the fastest healthiest growth. Once potted the high humidity was only needed to keep the potting mix from drying out, so I provided the "Humidity Domes" for 1 to 2 weeks only. The biggest problem was maintaining a moist environment in the potting mix.

The potting mix is the most problematic and sifting the mix to remove unwanted fines has helped. Getting the mix to both hold moisture and maintain aeration is the mix problem. This year I'm experimenting with mini SIPs to maintain the proper potting mix moisture and aeration. The tests have shown to me that pre-wetting the mix before planting and sub irrigation is able to maintain both moisture and air pocket within the soil to maintain aeration, even with a variety of mix ratios and materials.

Pete,
thakns for reply. unlike you, I am a complete novice to fig growing and cuttings propagation in general.
I'd like to be able to find what I am not doing right in order to better my process.
Therefore, besides just going by the looks and feels what perhaps most of veteran growers a doing so well, I would like  to turn to a quantifiable indicators  of the key environmental requirements for successful growth of cuttings.
So for my current batch I sifted PB and Perlite to remove smaller than 1/8" particles, added PM and a bit of dolomitic limestone, wetted the mix a day ahead
potting cuttings in it. Tested moisture by making sure it creates a ball in my hand (does not fall appart, when squeezed does not drip a drop of water either).To verify the moisture content, next day observed little condensation on the walls of cup.
Also, verified by weiging the dry soil in a 24 oz cup (cca 180 grams), wetted mix weighed 260 grams, therefore confirmed 45% moisture was reached.
Root growth is awesome and the color is white to slightly tan on 3-4 week old roots.
 But those cuttings that showed a bit green buds, seem to be changing bud color to grey scale:), and others that can not be hardened by gradual reduction of humidity are really concerning me. Especially for they grossly outnumber the ones that grow OK.

I don't have the ability to measure your parameters but I've noticed that pine bark is not good for young fig trees.  I have much better success with a high porosity mix like pro mix HP.  Once they're ready for a 5 gal pot pine bark is fine.  Ditching pine bark improved my success rate from 10% to 99%.  I found that the bark stayed wet and got slimy, indicating bacterial growth.  I rescued stagnant cuttings by transferring them from bark to pro mix hp.  You have to water pmhp much more often but it's been worth it.

As far as temps go, I only know what I set my thermostat at.  I'm sure the cuttings get exposed to higher temps right next to the heating mat.  I try to keep temps between 75 - 79 F, somewhat below your 30 C.  With that thermostat setting many of the ones right next to the heating mat died.  I assume they got cooked.  I don't know what the maximum temperature the mat can produce is but it makes me shy away from the upper end of your temp range.

Thanks to all for this interesting discussion. Please do not worry aboiut HIJACKING as long as we are talking about sucessfully getting a cutting to grow to the point of planting out then it is all good.

I'm still learning what does and doesn't work. Mainly I'm learning what doesn't work. The mix I'm using is equal parts coarse sand, pine bark mulch (nothing larger than 1/4" - 3/8" for the most part) and Peat moss. All mixed in a concrete mixer. I added just enough water to keep the PM from blowing away. The resulting mix feels light, damp and loose. After two days the mixture still feels damp but not wet and wipes off your hand without leaving a mud trail. I'm putting on lids today and tomorrow I'll see how much condensation I have inside on the walls and lid. I'm guessing I should have some but not but not great big beads of it. I guess as long as I see condensation in light amounts then I can assume the humidity is in the 85% - 90% range assuming a outside air temperature of 72F. Does that sound right? I'll start checking the soil temp in a couple of days once I think the air inside has stabilized.

Can_smokva,
I'm a novice at fig cultivation also, this year will be my third season growing figs.
My reasons for measuring and recording data is similar to yours, after reading all the anecdotes and recommendations, I decided to take actual measurements, since I didn't have a refrigerator on which to place the bag of cuttings : ). With actual measured data, the successes could be easily repeated. For cuttings, I have only added limestone to fresh peat moss, and always at the same ratio of 1 cup to 5 gallons of peat and the sifted pine bark mulch is rinsed, or flushed once with clean water to remove any excess acidic residue. My moisture test on the mix is moist to the touch and never wet, IMO if you can make a ball it is too wet, it should crumble apart when pressed into a ball. As far as light, I root the cuttings in the dark, and when potted they are placed in a south facing window without any artificial lighting. I've had very high success rate with 1-1-1 sifted Coir-Pine Bark Mulch-Perlite. The only problem with this mix was that it dried out too quickly so I am now using a 1-1-2-2 ratio of sifted Coir-Peat Moss- Pine Bark Mulch-Perlite. it has worked quite well in preliminary tests.
What data are you referring to for the 45% moisture content being optimal?


Bob C,
I have never had a problem with pine bark mulch, in fact in the 1 gallon containers with the 1-1-1 mix mentioned above , I had surprising root growth. the root tips grew into the pine bark chunks which caused them to produce multiple branches. The roots were "root pruned' by the bark pieces. I had posted to Greenfigs topic on pot temperatures...

Tupperware and damp orchid moss in my boiler room,temp is 80°.i clean my cuttings with 10% bleach,and get 80 two 90%.But you must start off with good cuttings.I don't care want or how you root them. The first few times I tried to root fig cuttings I got 0-10 % then I got cuttings from Marcus in Ohio,and then my % went to 75-80 %, and i did not change anything.

Pete S.
Under the links below bottom heat and temperature were discussed.
Page 11 in pdf document under lsecond link medium moisture is stated
Moisture

My pine bark was most of the mix.  Yours was 1/3rd.  I now use pine bark at 5% mixed into pro mix hp& 5% NAPA Floor Dry.  The Pro mix was drying out too fast.

I'm working with these two variables now specifically with fig cuttings.

Several little details working against me were present:
1) mix of cuttings of various thickness and freshness (stored energy levels) in the same bin,
2) mix of unwrapped, wrapped in parafilm tape, or dipped in the paraffin wax (above "soil" level ) in the same bin,
3) my failure to observe and detect that cup with condensation on its wall was actually dry, and cup without condensation on the wall was perfectly moist.
4) keeping lid on the bin closed 36 hours without venting

Lesson learned; for as long as I can not tell moisture of the medium by the look and feel, I will use digital kitchen scale and weigh it.
Having recorded weight of the cup, dry "soil" and wet 'soil', will constantly aim for 50% moisture by weight.
Temperature and humidity are readily readable, light 25W per square meter of area is sufficient.

Can_smokva,
Such high water levels may mean death to the fig cuttings...

Below is a document that was posted to another topic on bottom heat and cuttings.
A Published Document on propagating cuttings with recommendations on bottom heating and humidity in cutting propagation..