I checked existing posts on dormancy but none was relevant to answer my question. So I am asking botany or fig plants expert growing in colder areas.

 My location is zone 5a in the North and we already had a few nights below freezing, night temperature have been between 10C and freezing for a couple of weeks now but even the mature potted fig trees have green leaves (quite different situation from 5 years back). There is no option here to let it grow outside since we get -25C in mid-winter. Also, I cannot wait too long since after mid-October weather can bring expected (or unexpected) snow, slush and freezing temperatures that will make the task of bringing in potted fig collection inside.

 My question is if removing the green leaves and taking the pots inside the dark garage lead the plants to a healthy dormancy with no ill effects?

I have already removed loads of unripe figs that felt like hard golf balls.

It's less than ideal, but I've done something similar in Boston. I've found it is best to not take off the leaves though. After a week of no light they will fall off on their own. It's better to let the plant bring he sugars ans sap back into the wood naturally. As long as it's cool and the wood is already hardening off at the growth tips you should be fine with them in the garage. Make sure they don't get any light because they will only be in a light dormancy and can get really leggy really fast. 

Thanks.
I have previously brought them inside the garage with the leaves but after the leaves fall, the garage later smells like cat pee. 

Hi,
I wait for all leaves to fall first.
The shorter the winter the better IMO .

I tried once cutting the leaves, and that didn't help IMO - but at the same time the winter was brutal that year of 2012.
If you have a shady spot in  full wind - that spot will be colder and may help your trees go dormant faster.
I'd move the pots to such a spot and wait for the leaves to fall.
Try to give less water to your trees. If the weather is rainy by you, try to get the pots under a roof so the dirt does dry a bit faster - just monitor the trees so that they still have some water.
The weather is still mild here too ( like in too mild - no frost at all ) and the figtrees keep on ripening fruit like no year before ... Almost no leaf has fallen for now ...
I'll let my trees take advantage of that blessed weather. They get more time to harden of .

If you want the leaves to drop I was instructed by a jersey grower to cut the leaf leVing the stem attached to fall on its own.

I do the same and often store my fig trees in the garage at the end of summer when they still have leaves. As mentioned without much lights the leafs will fall within a few weeks.

The "schedule" I was given was this:
September 15 pinch buds to harden wood
November bring inside (or first real frost if it sticks)
December 15 clip leaves that remain leaving stems to prolong dormancy as muvh as possible to prevent trees from waking up in February.

I was also told that 1 cup of water per month is usually enough when dormant. This is my first year trying out dormancy, last year I tried to overwinter and the results weren't optimal

Growing Figs in the Rocky Mountains to produce Fig Wine and all you need to do is cover roots on top of ground and place card board boxes on top of hay!!

Thank you Akram for bringing up this topic and it's also relevant to me.  I have been wondering the same, especially with respect to the amount of rain we have now.  

Also thanks to jdsfrance for the suggestions.

I have just moved my really young fig plants into my kids' playhouse so they stay away from the rain and the frost (we are getting 0C/32F this weekend!).

Sorry Akram, this is not meant to hijack your thread, but I would like to ask a question along the same subject.  With respect to the really young fig plants (rooted earlier this year) that have only one main branch, should I try to preserve the main buds so they can continue to grow next season?  In this case, I will need to bring them inside early enough so the cold wouldn't kill off the buds.  Or pinch the bugs like Devin suggested? Or simply do nothing until the plants go completely dormant outside?

In past years I waited for first frost which usually occurred in late September which caused the leaves to naturally drop and to start dormancy. I then hauled the trees into the basement until April. However last year 2015 was different, there was no frost in September but we had a hard freeze in the first week of October with temperatures dropping into the mid teens (F) causing significant die back in many of the the trees.
This year, either rightly or not but mindful of a replay of last year, I stripped the trees of leaves and moved them into the basement at the end of September. The thought of a cellar full of leaves didn't seem desirable. So I'll just have to wait and see the results next spring.
As a side note, last year I bought several quart plants from Edible Landscaping in September. I kept these in the sun room until November when I stripped the leaves and put them into storage. They were fine this spring.

I also face this. Last year was a breeze. I put them in the garage once freezing temps hit, if nice out (above freezing) during the day I opened the garage.  Seem to work quite well. Leaves all fell off and growth completely stopped. I tried not to let the garage go below 25F, I used a heater if it did.

Based on what I'm seeing from my own trees and what others have told me Ottawan, the answer would be yes. If you remove leaves and store in a dark place 32-40° optimal but definitely under 50° they will go dormant anf all should be well. I was instructed to leave the leaf stems attached when cutting leaves to prevent mold and bacteria getting into the tree. That way the the tree closes the spot where leaf was attached while dropping the stem.

Thanks. I got wonderful informed input for action. However, it is raining and and expected snow tonight (may be just flurries) but we do expect -4C on Wednesday and that may take care of many leaves and those still hanging can be cut off for storage.

My main concern was that while giving the plants the benefit of 'no frost, good weather' this late in October can frequently end up with sudden snowfall and freezing temperatures in Ottawa making it hard at my age to move plants inside. Thanks for the fine input.

Bill, to answer your question, I always pinch the lead bud on a newly rooted plant when the plant is 15" to 18" tall to make it branch out. It will be better for you now to wait until spring to pinch it. Some varieties branch out early even if the lead branch is not pinched but some tend to grow high like a stick before branching which is not good for potted plants. But that is my practice and I like the results. Others may prefer differently.