For those of you who are going to hem your fabric before it gets pleated, this is a WARNING! Below is a problem we see time and time again, and it often ruins the fabric. The reason for this is the fact that after the fabric is hemmed, the length of one side has stretched and is longer than the other side. See the diagram below:
Below is an example of a hem that has been stretched after hemming. Since the fabric is not a perfect square it will be pleated off grain.
If we attempt to shirr the distance of the stretched hem, then we will have puckering as in the photo below:
As a result of this lengthening the quality of the pleating with be compromised. The image below shows how the hem of the skirt is crooked after pleating.
The more the fabric is stretched the greater the damage. To guarantee you will not have a problem, place your fabric on a table after hemming. If it lays flat and is square then you are good to go!