Rescue the date with DateTime.Today or something else and assign it to the EditorFor, since the date is a string.
<div class="form-group">
@Html.LabelFor(model => model.fecha, htmlAttributes: new { @class = "control-label col-md-2" })
<div class="col-md-10">
@Html.EditorFor(model => model.fecha)
@Html.ValidationMessageFor(model => model.fecha)
</div>
</div>