model post back with html attribute - asp.net-mvc

Question

I am having an issue with getting the value back in my ViewModel after a postback using a JQuery datepicker. The post back has the correct date with the form group StartDate that does not have a new htmlAttribute attached to the EditorFor. The StopDate does not post back the selected date due to the htmlAttribute. I would prefer not to use a hidden field to send back the data since I know this should work. Anybody have any suggestions?
<div class="form-group" id="StartDate">
#Html.LabelFor(model => model.StartDate, htmlAttributes: new { #class = "control-label col-md-2" })
<div class="col-md-10">
#Html.EditorFor(model => model.reportTimeEntries[0].StartDate, "","StartDate" )
#Html.ValidationMessageFor(model => model.StartDate, "", new { #class = "text-danger" })
#Html.HiddenFor(model => model.StartDate)
</div>
</div>
<div class="form-group" id="StopDate">
#Html.LabelFor(model => model.StopDate, htmlAttributes: new { #class = "control-label col-md-2" })
<div class="col-md-10">
#Html.EditorFor(model => model.reportTimeEntries[0].StopDate, new { htmlAttributes = new { #class = "form-control date" } })
#Html.ValidationMessageFor(model => model.StopDate, "", new { #class = "text-danger" })
</div>
</div>
$('#StartDate .date').datepicker({
'format': 'mm/dd/yyyy',
'autoclose': true
});
$('#StopDate .date').datepicker({
'format': 'mm/dd/yyyy',
'autoclose': true
});
UPDATE
So it seems that this has worked by adding this to my ViewModel. The 'Nullable' section seems to allow the date to be posted back.
ViewModel
[DataType(DataType.DateTime)]
[Display(Name = "Stop Date")]
[DisplayFormat(DataFormatString = "{0:MM/dd/yyyy}", ApplyFormatInEditMode = true)]
public Nullable<System.DateTime> StopDate { get; set; }
View
<div class="form-group" id="StopDate">
#Html.LabelFor(model => model.StopDate, htmlAttributes: new { #class = "control-label col-md-2" })
<div class="col-md-10">
#Html.EditorFor(model => model.reportTimeEntries[0].StopDate, "","StopDate",new { htmlAttributes = new { #class = "form-control date" } })
#Html.ValidationMessageFor(model => model.StopDate, "", new { #class = "text-danger" })
</div>
</div>